Tag Archives: High Energy Physics – Phenomenology

Distinguishing nanohertz gravitational wave sources through the observations of ultracompact minihalos [CEA]

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http://arxiv.org/abs/2305.15100


The common-spectrum process observed by pulsar-timing arrays is interpreted as stochastic gravitational wave backgrounds originating from various sources in the early Universe. Along with generating gravitational waves, we find energy density perturbations also arise with the sources such as bubble collisions and sound waves during first-order phase transitions, cosmic strings, domain walls, condensate fragmentation, and primordial curvature perturbations from inflation. These perturbations can lead to the formation of abundant ultracompact minihalos. Currently, the observational precision is inadequate for discriminating between different models. Then, ongoing and future astrophysical observations of ultracompact minihalos can help to distinguish and constrain the gravitational-wave sources in the nanohertz and $\mu$Hz bands.

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J. Liu
Thu, 25 May 23
64/64

Comments: 7 pages, 1 figure, 1 table

Dark Sectors with Mass Thresholds Face Cosmological Datasets [CEA]

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http://arxiv.org/abs/2305.14166


Interacting dark sectors may undergo changes in the number of their relativistic species during the early universe, due to a mass threshold $m$ (similar to changes in the Standard Model bath), and in doing so affect the cosmic history. When such changes occur close to recombination, i.e., for $m\sim (0.1-10)~\text{eV}$, the stringent bound on the effective number of neutrino species, $N_{\text{eff}}$, can be relaxed and the value of the Hubble expansion rate $H_0$ inferred from Cosmic Microwave Background (CMB) observations raised. We search for such sectors (with and without mass thresholds) in the latest cosmological datasets, including the full-shape (FS) of BOSS DR12 galaxy power spectrum. We perform a detailed analysis, accounting for the choice of prior boundaries and additionally exploring the possible effects of dark sector interactions with (a fraction of) the dark matter. We find $\Delta N_{\text{eff}}\leq 0.55\, (0.46)$ at 95% C.L. with (without) a mass threshold. While a significantly larger Hubble rate is achieved in this scenario, $H_0=69.01^{+0.66}_{-1.1}$, the overall fit to CMB+FS data does not provide a compelling advantage over the $\Lambda$CDM model. Furthermore, we find that dark matter interactions with the dark sector do not significantly improve the (matter fluctuations) $S_8$ tension with respect to the $\Lambda$CDM model. Our work provides model-independent constraints on (decoupled) dark sectors with mass thresholds around the eV scale.

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I. Allali, F. Rompineve and M. Hertzberg
Wed, 24 May 23
81/81

Comments: 18 + 18 pages, 38 figures and tables

Explaining the GeV excess with exploding black holes [HEAP]

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http://arxiv.org/abs/2305.13434


Black holes may form in present-day collapse of microscopic structures of dark matter. We show that, if microstructure black holes (MSBH) with mass $m\sim 10^{13}~g$ are produced, the spectrum of gamma rays from their evaporation agrees remarkably well with the GeV excess observed by Fermi Gamma-ray Space Telescope, while still avoiding all observational constraints. We also discuss the generic requirements for MSBHs to explain the GeV excess.

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Z. Picker and A. Kusenko
Wed, 24 May 23
81/81

Comments: letter—4 pages 1 figure

Clustering of Primordial Black Holes from QCD Axion Bubbles [CEA]

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http://arxiv.org/abs/2305.13023


We study the clustering of primordial black holes (PBHs) and axion miniclusters produced in the model proposed to explain the LIGO/Virgo events or the seeds of the supermassive black holes (SMBHs) in arXiv:2006.13137. It is found that this model predicts large isocurvature perturbations due to the clustering of PBHs and axion miniclusters, from which we obtain stringent constraints on the model parameters. Specifically, for the axion decay constant $f_a=10^{16}~\mathrm{GeV}$, which potentially accounts for the seeds of the SMBHs, the PBH fraction in dark matter should be $f_\mathrm{PBH}\lesssim7\times 10^{-10}$. Assuming that the mass of PBHs increases by more than a factor of $\mathcal{O}(10)$ due to accretion, this is consistent with the observed abundance of SMBHs. On the other hand, for $f_a=10^{17}~\mathrm{GeV}$ required to produce PBHs of masses detected in the LIGO/Virgo, the PBH fraction should be $f_\mathrm{PBH}\lesssim6\times 10^{-8}$, which may be too small to explain the LIGO/Virgo events, although there is a significant uncertainty in calculating the merger rate in the presence of clustering.

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K. Kasai, M. Kawasaki, N. Kitajima, et. al.
Tue, 23 May 23
77/77

Comments: 18 pages, 11 figures

Halo formation and evolution in SFDM and CDM: new insights from the fluid approach [GA]

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http://arxiv.org/abs/2305.12982


(abridged) We present simulations of halo formation and evolution in scalar field dark matter (SFDM) cosmologies in the Thomas-Fermi regime, aka SFDM-TF", where a strong repulsive 2-particle self-interaction (SI) is included, being a valuable alternative to CDM, with the potential to resolve itscusp-core” problem. In general, SFDM behaves like a quantum fluid. Previous literature has presented two fluid approximations for SFDM-TF, as well as simulations of halo formation. These results confirmed earlier expectations and are generally in mutual agreement, but discrepancies were also reported. Therefore, we perform dedicated 3D cosmological simulations for the SFDM-TF model, applying both fluid approximations, as well as for CDM. Our results are very well in accordance with previous works and extend upon them, in that we can explain the reported discrepancies as a result of different simulation setups. We find some interesting details: The evolution of both SFDM-TF and CDM halos follows a 2-stage process. In the early stage, the density profile in the center becomes close to a $(n=1.5)$-polytropic core, dominated by an “effective” velocity-dispersion pressure $P_{\sigma}$ which is common to both dark matter models. Consecutively, for CDM halos, the core transitions into a central cusp. In SFDM-TF halos, the additional pressure $P_\text{SI}$ due to SI determines the second stage of the evolution, where the central region follows closely a $(n=1)$-polytropic core, embedded in a nearly isothermal envelope, i.e. the outskirts are similar to CDM. We also encounter a new effect, namely a late-time expansion of both polytropic core plus envelope, because the size of the almost isothermal halo envelope is affected by the expansion of the background universe. So, an initial primordial core of $\sim 100$ pc can evolve into a larger core of $\gtrsim 1$ kpc, even without feedback from baryons.

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H. Foidl, T. Rindler-Daller and W. Zeilinger
Tue, 23 May 23
77/77

Comments: submitted to Phys.Rev.D; 26 pages, 16 figures

Fast Neutrino Flavor Conversions can Help and Hinder Neutrino-Driven Explosions [HEAP]

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http://arxiv.org/abs/2305.11207


We present the first simulations of core-collapse supernovae (CCSNe) in axial symmetry (2D) with feedback from fast neutrino flavor conversion (FFC). Our schematic treatment of FFCs assumes instantaneous flavor equilibration under the constraint of lepton-number conservation. Systematically varying the spatial domain where FFCs are assumed to occur, we find that they facilitate SN explosions in low-mass (9-12 solar masses) progenitors that otherwise explode with longer time delays, whereas FFCs weaken the tendency to explode of higher-mass (around 20 solar masses) progenitors.

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J. Ehring, S. Abbar, H. Janka, et. al.
Mon, 22 May 23
14/60

Comments: 7 pages, 4 figures, submitted to PRL

Engineering the sensitivity of macroscopic physical systems to variations in the fine-structure constant [CL]

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http://arxiv.org/abs/2305.11264


Experiments aimed at searching for variations in the fine-structure constant $\alpha$ are based on spectroscopy of transitions in microscopic bound systems, such as atoms and ions, or resonances in optical cavities. The sensitivities of these systems to variations in $\alpha$ are typically on the order of unity and are fixed for a given system. For heavy atoms, highly charged ions and nuclear transitions, the sensitivity can be increased by benefiting from the relativistic effects and favorable arrangement of quantum states. This article proposes a new method for controlling the sensitivity factor of macroscopic physical systems. Specific concepts of optical cavities with tunable sensitivity to $\alpha$ are described. These systems show qualitatively different properties from those of previous studies of the sensitivity of macroscopic systems to variations in $\alpha$, in which the sensitivity was found to be fixed and fundamentally limited to an order of unity. Although possible experimental constraints attainable with the specific optical cavity arrangements proposed in this article do not yet exceed the present best constraints on $\alpha$ variations, this work paves the way for developing new approaches to searching for variations in the fundamental constants of physics.

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B. Zjawin, M. Bober, R. Ciuryło, et. al.
Mon, 22 May 23
17/60

Comments: N/A

Gravitational waves from walls bounded by strings in $SO(10)$ model of pseudo-Goldstone dark matter [CL]

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http://arxiv.org/abs/2305.11775


We explore the gravitational wave spectrum generated by string-wall structures in an $SO(10)$ ($Spin(10)$) based scenario of pseudo-Goldstone boson dark matter (pGDM) particle. This dark matter candidate is a linear combination of the Standard Model (SM) singlets present in the 126 and 16 dimensional Higgs fields. The Higgs $126$-plet vacuum expectation value (VEV) $\left<126_H\right>$ leaves unbroken the $\mathbb{Z}_2$ subgroup of $\mathbb{Z}_4$, the center of $SO(10)$. Among other things, this yields topologically stable cosmic strings with a string tension $\mu \sim \left<126_H\right>^2$. The subsequent (spontaneous) breaking of $\mathbb{Z}_2$ at a significantly lower scale by the $16$-plet VEV $\left<16_H\right>$ leads to the appearance of domain walls bounded by the strings produced earlier. We display the gravitational wave spectrum for $G \mu$ values varying between $10^{-15}$ and $10^{-9}$ ($\left<126_H\right>\sim 10^{11}$ – $10^{14}$ GeV), and $\left<16_H\right>\sim 0.1$ – $10^3$ TeV range ($G$ denotes Newton’s constant.) These predictions can be tested, as we show, by a variety of (proposed) experiments including LISA, ET, CE and others.

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R. Maji, W. Park and Q. Shafi
Mon, 22 May 23
22/60

Comments: 8 pages, 3 figures

Minimal Preheating [CL]

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http://arxiv.org/abs/2305.11246


An oscillating inflaton field induces small amplitude oscillations of the Hubble parameter at the end of inflation. These Hubble parameter induced oscillations, in turn, trigger parametric particle production of all light fields, even if they are not directly coupled to the inflaton. We here study the induced particle production for a light scalar field (e.g. the Standard Model Higgs field) after inflation as a consequence of this effect. Our analysis yields a model-independent lower bound on the efficiency of energy transfer from the inflaton condensate to particle excitations.

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R. Brandenberger, V. Kamali and R. Ramos
Mon, 22 May 23
30/60

Comments: 9 pages, 7 figures

Searching for Scalar Ultralight Dark Matter with Optical Fibers [CL]

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http://arxiv.org/abs/2305.11205


We consider optical fibers as detectors for scalar ultralight dark matter (UDM) and propose using a fiber-based interferometer to search for scalar UDM with particle mass in the range $10^{-17} – 10^{-13}$ eV/$c^2$ $\left(10^{-3}- 10 \text{ Hz}\right)$. Composed of a solid core and a hollow core fiber, the proposed detector would be sensitive to relative oscillations in the fibers’ refractive indices due to scalar UDM-induced modulations in the fine-structure constant $\alpha$. We predict that, implementing detector arrays or cryogenic cooling, the proposed optical fiber-based scalar UDM search has the potential to reach new regions of the parameter space. Such a search would be particularly well-suited to probe for a Solar halo of dark matter with a sensitivity exceeding that of previous DM searches over the particle mass range $7\times 10^{-17} – 2\times 10^{-14}$ eV/$c^2$.

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J. Manley, R. Stump, R. Petery, et. al.
Mon, 22 May 23
43/60

Comments: N/A

The origin of low-redshift event rate excess as revealed by the low-luminosity GRBs [HEAP]

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http://arxiv.org/abs/2305.11380


The relation between the event rate of long Gamma-Ray Bursts at low redshift and the star formation rate is still controversial, especially in the low-redshift end. Dong et al. confirmed that the Gamma-Ray Burst rate always exceeds the star formation rate at low-redshift of z < 1 in despite of the sample completeness. However, the reason of low-redshift excess is still unclear. Considering low-luminosity bursts with smaller redshift generally, we choose three Swift long burst samples and classify them into low- and high-luminosity bursts in order to check whether the low-redshift excess is existent and if the excess is biased by the sample size and completeness. To degenerate the redshift evolution from luminosity, we adopt the non-parametric method to study the event rate of the two types of long bursts in each sample. It is found that the high-luminosity burst rates are consistent with the star formation rate within the whole redshift range while the event rates of low-luminosity bursts exceed the star formation rate at low redshift of z < 1. Consequently, we conclude that the low-redshift excess is contributed by the low-luminosity bursts with possibly new origins unconnected with the star formation, which is also independent of the sample size and the sample completeness.

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X. Dong, Z. Zhang, Q. Li, et. al.
Mon, 22 May 23
51/60

Comments: 15 pages, 5 figures, sumitted

EDGES and JWST with 21cm global signal emulator [CEA]

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http://arxiv.org/abs/2305.11441


The 21cm global signal is an important probe to reveal the properties of the first astrophysical objects and the processes of the structure formation from which one can constrain astrophysical and cosmological parameters. To extract the information of such parameters, one needs to efficiently evaluate the 21cm global signal for statistical analysis. First we developed an artificial neural network-based emulator to predict the 21cm global signal, which works with significantly less computational cost and high precision. Then we apply our emulator to demonstrate the parameter estimation based on the Bayesian analysis by using the publicly available EDGES low-band data. We find that the result is sensitive to the foreground model, the assumption of noise, and the frequency range used in the analysis. The Bayesian evidence suggests the models with higher order polynomial function and enhanced noise are preferred. We also compare models suggested from the EDGES low-band data and the ones from recent JWST measurements of the galaxy luminosity function at $z=16$. We find that the model which produces the 21cm absorption line at $z\approx15$ is well consistent with the central value of the observed luminosity function at $z=16$.

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S. Yoshiura, T. Minoda and T. Takahashi
Mon, 22 May 23
56/60

Comments: 11 pages, 12 figures, 3 tables. Comments welcome

Cosmic string bursts in LISA [CL]

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http://arxiv.org/abs/2305.11653


Cosmic string cusps are sources of short-lived, linearly polarised gravitational wave bursts which can be searched for in gravitational wave detectors. We assess the capability of LISA to detect these bursts using the latest LISA configuration and operational assumptions. For such short bursts, we verify that LISA can be considered as “frozen”, namely that one can neglect LISA’s orbital motion. We consider two models for the network of cosmic string loops, and estimate that LISA should be able to detect 1-3 bursts per year assuming a string tension $G\mu \approx 10^{-11} – 10^{-10.5}$ and detection threshold $\rm{SNR} \ge 20$. Non-detection of these bursts would constrain the string tension to $G\mu\lesssim 10^{-11}$ for both models.

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P. Auclair, S. Babak, H. Leclere, et. al.
Mon, 22 May 23
60/60

Comments: 6 pages

Cogenesis of matter and dark matter from triplet fermion seesaw [CL]

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http://arxiv.org/abs/2305.11138


We propose a simple model in the type-III seesaw framework to explain the recently reported W-mass anomaly by CDF-II collaboration, neutrino mass, asymmetric dark matter, and baryon asymmetry of the Universe. We extend the standard model with a vector-like singlet lepton ($\chi$) and a hypercharge zero scalar triplet ($\Delta$) in addition to three hypercharge zero triplet fermions($\Sigma_i~,i=1,2,3$). A $Z_2$ symmetry is imposed under which $\chi$ and $\Delta$ are odd, while all other particles are even. As a result, the lightest $Z_2$ odd particle $\chi$ behaves as a candidate of dark matter. In the early Universe, the CP-violating out-of-equilibrium decay of heavy triplet fermions to the Standard Model lepton ($L$) and Higgs ($H$) generate a net lepton asymmetry, while that of triplet fermions to $\chi$ and $\Delta$ generate a net asymmetric dark matter. The lepton asymmetry is converted to the required baryon asymmetry of the Universe via the electroweak sphalerons, while the asymmetry in $\chi$ remains as a dark matter relic that we observe today. We introduce a singlet scalar $\phi$, with mass $m_\phi < m_\chi$, which not only assists to deplete the symmetric component of $\chi$ through the annihilation process: $\bar{\chi} \chi \to \phi \phi$ but also paves a path to detect dark matter $\chi$ at direct search experiments through $\phi-H$ mixing. The $Z_2$ symmetry is broken softly resulting in an unstable asymmetric dark matter with mass ranging from a few MeV to a few tens of GeV. The softly broken $Z_2$ symmetry also induces a vacuum expectation value (vev) of $\Delta$ due to which the asymmetry in $\Delta$ disappears. Moreover, the vev of $\Delta$ enhances the W-boson mass as reported by CDF-II collaboration with $7\sigma$ statistical significance, while keeping the $Z$-boson mass intact.

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S. Mahapatra, P. Paul, N. Sahu, et. al.
Fri, 19 May 23
8/46

Comments: 33 pages, 19 captioned figures

The Photon Content of the Neutron [CL]

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http://arxiv.org/abs/2305.10497


In this work, we complete our CT18qed study with the neutron’s photon parton distribution function (PDF), which is essential for the nucleus scattering phenomenology. Two methods, CT18lux and CT18qed, based on the LUXqed formalism and the DGLAP evolution, respectively, to determine the neutron’s photon PDF have been presented. Various low-$Q^2$ non-perturbative variations have been carefully examined, which are treated as additional uncertainties on top of those induced by quark and gluon PDFs. The impacts of the momentum sum rule as well as isospin symmetry violation have been explored, and turn out to be negligible. A detailed comparison with other neutron’s photon PDF sets has been performed, which shows a great improvement in the precision and a reasonable uncertainty estimation in our results. Finally, two phenomenological implications are demonstrated with photon-initiated processes: neutrino-nucleus $W$-boson production, which is important for the near-future TeV–PeV neutrino observations, and the axion-like particle production at a high-energy muon beam-dump experiment.

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K. Xie, B. Zhou and T. Hobbs
Fri, 19 May 23
9/46

Comments: 34 pages, 22 figures

The warm inflation story [CL]

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http://arxiv.org/abs/2305.10879


Warm inflation has normalized two ideas in cosmology, that in the early universe the initial primordial density perturbations generally could be of classical rather than quantum origin and that during inflation, particle production from interactions amongst quantum field, and its backreaction effects, can occur concurrent with inflationary expansion. When we first introduced these ideas, both were met with resistance, but today they are widely accepted as possibilities with many models and applications based on them, which is an indication of the widespread influence of warm inflation. Open quantum field theory, which has been utilized in studies of warm inflation, is by now a relevant subject in cosmology, in part due to this early work. In this review I first discuss the basic warm inflation dynamics. I then outline how to compute warm inflation dynamics from first principles quantum field theory (QFT) and in particular how a dissipative term arises. Warm inflation models can have an inflaton mass bigger than the Hubble scale and the inflaton field excursion can remain sub-Planckian, thus overcoming the most prohibitive problems of inflation model building. I discuss the early period of my work in developing warm inflation that helped me arrive at these important features of its dynamics. Inflationary cosmology today is immersed in hypothetical models, which by now are acting as a diversion from reaching any endgame in this field. I discuss better ways to approach model selection and give necessary requirements for a well constrained and predictive inflation model. I point out a few warm inflation models that could be developed to this extent. I discuss how at this stage more progress would be made in this subject by taking a broader view on the possible early universe solutions that include not just inflation but the diverse range of options.

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A. Berera
Fri, 19 May 23
23/46

Comments: N/A

Primordial Black Hole Reheating [CL]

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http://arxiv.org/abs/2305.10518


Post-inflationary reheating phase is usually said to be solely governed by the decay of coherently oscillating inflaton into radiation. In this submission, we explore a new avenue toward reheating through the evaporation of primordial black holes (PBHs). After the inflation, if PBHs form, depending on its initial mass, abundance, and inflaton coupling with the radiation, we found two physically distinct possibilities of reheating the universe. In one possibility, the thermal bath is solely obtained from the decay of PBHs while inflaton plays the role of dominant energy component in the entire process. In the other possibility, we found that PBHs itself dominate the total energy budget of the Universe during the course of evolution, and then its subsequent evaporation leads to radiation dominated universe. Furthermore, we analyze the impact of both monochromatic and extended PBH mass functions and estimate the detailed parameter ranges for which those distinct reheating histories are realized.

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M. Haque, E. Kpatcha, D. Maity, et. al.
Fri, 19 May 23
44/46

Comments: 17 pages, 9 figures

An optimized search for dark matter in the galactic halo with HAWC [HEAP]

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http://arxiv.org/abs/2305.09861


The Galactic Halo is a key target for indirect dark matter detection. The High Altitude Water Cherenkov (HAWC) observatory is a high-energy (~300 GeV to >100 TeV) gamma-ray detector located in central Mexico. HAWC operates via the water Cherenkov technique and has both a wide field of view of 2 sr and a >95% duty cycle, making it ideal for analyses of highly extended sources. We made use of these properties of HAWC and a new background-estimation technique optimized for extended sources to probe a large region of the Galactic Halo for dark matter signals. With this approach, we set improved constraints on dark matter annihilation and decay between masses of 10 and 100 TeV. Due to the large spatial extent of the HAWC field of view, these constraints are robust against uncertainties in the Galactic dark matter spatial profile.

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A. Albert, R. Alfaro, C. Alvarez, et. al.
Thu, 18 May 23
20/67

Comments: 19 pages, 14 figures

Multimessenger Constraints on Radiatively Decaying Axions from GW170817 [CL]

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http://arxiv.org/abs/2305.10327


The metastable hypermassive neutron star produced in the coalescence of two neutron stars can copiously produce axions that radiatively decay into $\mathcal{O}(100)$~MeV photons. These photons can form a fireball with characteristic temperature smaller than $1\rm\, MeV$. By relying on X-ray observations of GW170817/GRB 170817A with CALET CGBM, Konus-Wind, and Insight-HXMT/HE, we present new bounds on the axion-photon coupling for axion masses in the range $1$-$400\,\rm MeV$. We exclude couplings down to $5\times 10^{-11}\,\rm GeV^{-1}$, complementing and surpassing existing constraints. Our approach can be extended to any feebly-interacting particle decaying into photons.

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M. Diamond, D. Fiorillo, G. Marques-Tavares, et. al.
Thu, 18 May 23
28/67

Comments: 5 pages, 3 figures + 4 pages, 2 figures

SRF Cavity Searches for Dark Photon Dark Matter: First Scan Results [CL]

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http://arxiv.org/abs/2305.09711


We present the first use of a tunable superconducting radio frequency cavity to perform a scan search for dark photon dark matter with novel data analysis strategies. We mechanically tuned the resonant frequency of a cavity embedded in the liquid helium with a temperature of $2$ K, scanning the dark photon mass over a frequency range of $1.37$ MHz centered at $1.3$ GHz. By exploiting the superconducting radio frequency cavity’s considerably high quality factors of approximately $10^{10}$, our results demonstrate the most stringent constraints to date on a substantial portion of the exclusion parameter space, particularly concerning the kinetic mixing coefficient between dark photons and electromagnetic photons $\epsilon$, yielding a value of $\epsilon < 2.2 \times 10^{-16}$.

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Z. Tang, B. Wang, Y. Chen, et. al.
Thu, 18 May 23
29/67

Comments: 11 pages, 7 figures

Gravitational Positivity for Phenomenologists: Dark Gauge Boson in the Swampland [CL]

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http://arxiv.org/abs/2305.10058


The gravitational positivity bound gives quantitative “swampland” constraints on low-energy effective theories inside theories of quantum gravity. We give a comprehensive discussion of this bound for those interested in applications to phenomenological model building. We present a practical recipe for deriving the bound, and discuss subtleties relevant for realistic models. As an illustration, we study the positivity bound on the scattering of the massive gauge bosons in the Higgs/St\”{u}ckelberg mechanism. Under certain assumptions on gravitational amplitudes at high energy, we obtain a lower bound $m_{V} \gtrsim \Lambda_\mathrm{UV}^2 /g M_\mathrm{Pl}$ on the gauge boson mass $m_V$, where $g$ is the coupling constant of the gauge field, $M_\mathrm{Pl}$ is the reduced Planck mass and $\Lambda_\mathrm{UV}$ is the ultraviolet cutoff of the effective field theory. This bound can strongly constrain new physics models involving a massive gauge boson.

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K. Aoki, T. Noumi, R. Saito, et. al.
Thu, 18 May 23
38/67

Comments: 30 pages, 12 figures

Constraints on the spectral signatures of superconducting cosmic strings [CEA]

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http://arxiv.org/abs/2305.09816


If they exist, networks of superconducting cosmic strings are capable of injecting copious amounts of electromagnetic energy into the background over a broad range of frequencies. We study this injection both analytically, as well as numerically using the thermalization code CosmoTherm. With our refined analytic formalism, we update constraints from CMB spectral distortions by following the injection of entropy, as well as energy, on the amplitude of the $\mu$-distortion, leading to a significant improvement in those limits. Furthermore, we utilize the full shape of the distorted spectrum from CosmoTherm to include constraints from non-$\mu$, non-$y$ type distortions. Additionally, we use the outputs for the ionization history and global 21cm signal to derive and update constraints on string model parameters using measurements from other datasets. Analysis of CMB anisotropies provides the most stringent constraints, though with a slightly modified shape and strength when compared to previous results. Modifications of the reionization history provide new bounds in the high current domain, and we also find that the observations of the low-frequency radio background probe a small region of parameter space not explored by other datasets. We also analyze global $21$-cm constraints, and find that the inclusion of soft photon heating plays a crucial role, essentially removing any constraints in the considered parameter domain. Spectral distortion measurements from COBE/FIRAS are covered by other constraints, but our conservative forecast shows that a PIXIE-type satellite would probe important unexplored regions of parameter space.

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B. Cyr, J. Chluba and S. Acharya
Thu, 18 May 23
55/67

Comments: 21 pages, 24 figures, comments welcome!

Strange stars properties calculated in the framework of the Field Correlator Method [CL]

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http://arxiv.org/abs/1104.3352


We calculate the strange star properties in the framework of the Field Correlator Method. We find that for the values of the gluon condensate $G_2=0.006\;{\rm GeV}^4$ and $G_2=0.0068\;{\rm GeV}^4$, which give a critical temperature $T_c\sim170\;{\rm MeV}$ at $\mu_c=0$, the sequences of strange stars are compatible with some of the semi-empirical mass-radius relations and data obtained from astrophysical observations.

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F. Pereira
Wed, 17 May 23
6/67

Comments: 26 pages, 10 figures

Cosmology of Single Species Hidden Dark Matter [CEA]

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http://arxiv.org/abs/2305.08943


Cosmology and astrophysics provide various ways to study the properties of dark matter even if they have negligible non-gravitational interactions with the Standard Model particles and remain hidden. We study a type of hidden dark matter model in which the dark matter is completely decoupled from the Standard Model sector except gravitationally, and consists of a single species with a conserved comoving particle number. This category of hidden dark matter includes models that act as warm dark matter but is more general. In particular, in addition to having an independent temperature from the Standard Model sector, it includes cases in which dark matter is in its own thermal equilibrium or is free-streaming, obeys fermionic or bosonic statistics, and processes a chemical potential that controls the particle occupation number. While the usual parameterization using the free-streaming scale or the particle mass no longer applies, we show that all cases can be well approximated by a set of functions parameterized by only one parameter as long as the chemical potential is nonpositive: the characteristic scale factor at the time of the relativistic-to-nonrelativistic transition. We study the constraints from Big Bang Nucleosynthesis, the cosmic microwave background, the Lyman-$\alpha$ forest, and the smallest halo mass. We show that the most significant phenomenological impact is the suppression of the small-scale matter power spectrum — a typical feature when the dark matter has a velocity dispersion or pressure at early times. So far, small dark matter halos provide the strongest constraint, limiting the transition scale factor to be no larger than $\sim1.4\times10^{-4}$ times the scale factor at matter-radiation equality.

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W. Lin, X. Chen, H. Ganjoo, et. al.
Wed, 17 May 23
21/67

Comments: 24 pages, 3 tables, 8 figures, comments welcome

Synthesis of elements in compact stars in pycnonuclear reactions with Carbon isotopes: Quasibound states versus states of zero-points vibrations [CL]

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http://arxiv.org/abs/2305.09389


(1) Purpose: Conditions of formation of compound nuclear system needed for synthesis of heavy nuclei in pycnonuclear reactions in compact stars are studied on a quantum mechanical basis. (2) Methods: Method of multiple internal reflections is generalized for pycnoreactions in compact stars with new calculations of quasibound spectra and spectra of zero-point vibrations. (3) Results: Peculiarities of the method are analyzed for reaction with isotopes of Carbon. The developed method takes into account continuity and conservation of quantum flux (describing pycnonuclear reaction) inside the full spacial region of reaction including nuclear region. This gives appearance of new states (called as quasibound states), in which compound nuclear systems of Magnesium are formed with the largest probability. These states have not been studied yet in synthesis of elements in stars. Energy spectra of zero-point vibrations and spectra of quasibound states are estimated with high precision for reactions with isotopes of Carbon. At the first time influence of plasma screening on quasibound states and states of zero-point vibrations in pycnonuclear reactions has been studied. (4) Conclusion: The probability of formation of compound nuclear system in quasibound states in pycnonuclear reaction is essentially larger than the probability of formation of this system in states of zero-point vibrations studied by Zel’dovich and followers. So, synthesis of Magnesium from isotopes of Carbon is more probable through the quasibound states than through the states of zero-point vibrations in compact stars. Energy spectra of zero-point vibrations are changed essentially after taking plasma screening into account. Analysis shows that from all studied isotopes of Magnesium only \isotope[24]{Mg} is stable after synthesis at energy of relative motion of 4.881~MeV of incident nuclei \isotope[12]{C}.

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S. Maydanyuk, G. Wolf and K. Shaulskyi
Wed, 17 May 23
39/67

Comments: 15 pages, 4 captured figures, 4 captured tables. arXiv admin note: text overlap with arXiv:2205.13895

Primordial black holes and inflation from double-well potentials [CEA]

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http://arxiv.org/abs/2305.09630


We investigate the formation of large peaks in the inflationary curvature power spectrum from double-well potentials. In such scenarios, the initial CMB spectrum is created at large field values. Subsequently, the inflaton will cross one of the minima and will decelerate rapidly as it reaches the local maximum at the origin, either falling back or crossing it. During this final phase, a significant peak in the curvature power spectrum can be generated. Our analysis reveals that this class of models produces more pronounced peaks than the more commonly studied quasi-inflection point scenarios with less tuning for the model parameters. Finally, we construct an explicit theoretically motivated inflationary scenario that is consistent with the latest CMB observations and capable of generating sufficiently large curvature perturbations for primordial black holes.

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A. Karam, N. Koivunen, E. Tomberg, et. al.
Wed, 17 May 23
44/67

Comments: 22 pages, 5 figures

On the anomalous mass defect of strange stars in the Field Correlator Method [CL]

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http://arxiv.org/abs/1601.04284


We investigate general aspects of the mass defects of strange stars in the context of the Field Correlator Method, without magnetic field. The main parameters of the model that enter the corresponding nonperturbative equation of state of the quark gluon plasma are the gluon condensate $G_2$ and the large distance static $Q{\bar Q}$ potential $V_1$. We calculate mass defects of stellar configurations in the central density range $11<\log\rho_c<18$. In general, the mass defects are strongly dependent on the model parameters. For a large range of values of $G_2$ and $V_1$, we obtain anomalous mass defects with magnitudes around $10^{53}\,$erg\,, of the same order of the observed energies of gamma-ray bursts and neutrino emissions in SN1987A, and of the theoretically predicted energies of the quark-novae explosions.

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F. Pereira
Wed, 17 May 23
45/67

Comments: 24 pages, 6 figures

Cold New Early Dark Energy pulls the trigger on the $H_0$ and $S_8$ tensions: a simultaneous solution to both tensions without new ingredients [CEA]

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http://arxiv.org/abs/2305.08895


In this work, we show that the Cold New Early Dark Energy (Cold NEDE) model in its original form can solve both the Hubble tension and the $S_8$ tension without adding any new ingredients at the fundamental level. So far, it was assumed that the trigger field in the Cold NEDE model is completely subdominant. However, relaxing this assumption and letting the trigger field contribute a mere $0.5\%$ of the total energy density leads to a resolution of the $S_8$ tension while simultaneously improving it as a solution to the $H_0$ tension. Fitting this model to baryonic acoustic oscillations, large-scale-structure, supernovae (including a SH0ES prior), and cosmic microwave background data, we report a preferred NEDE fraction of $f_\mathrm{NEDE}= 0.134^{+0.032}_{-0.025}$ ($68\%$ C.L.), lifting its Gaussian evidence for the first time above $5\sigma$ (up from $4 \sigma$ when the trigger contribution to dark matter is negligible). At the same time, we find the new concordance values $H_0 = 71.71 \pm 0.88 \,\mathrm{km}\, \mathrm{sec}^{-1}\, \mathrm{Mpc}^{-1}$ and $S_8 = 0.793 \pm 0.018$. Excluding large-scale structure data and the SH$_0$ES prior, both Gaussian tensions are reduced below the $2 \sigma$ level.

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J. Cruz, F. Niedermann and M. Sloth
Wed, 17 May 23
46/67

Comments: 40 pages, 7 figures, 8 tables

The uncertainties on the EFT coupling limits for direct dark matter detection experiments stemming from uncertainties of target properties [CL]

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http://arxiv.org/abs/2305.08991


Direct detection experiments are still one of the most promising ways to unravel the nature of dark matter. To fully understand how well these experiments constrain the dark matter interactions with the Standard Model particles, all the uncertainties affecting the calculations must be known. It is especially critical now because direct detection experiments recently moved from placing limits only on the two elementary spin independent and spin dependent operators to the complete set of possible operators coupling dark matter and nuclei in non-relativistic theory. In our work, we estimate the effect of nuclear configuration-interaction uncertainties on the exclusion bounds for one of the existing xenon-based experiments for all fifteen operators. We find that for operator number 13 the $\pm1\sigma$ uncertainty on the coupling between the dark matter and nucleon can reach more than 50% for dark matter masses between 10 and 1000 GeV. In addition, we discuss how quantum computers can help to reduce this uncertainty.

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D. Heimsoth, B. Lem, A. Suliga, et. al.
Wed, 17 May 23
49/67

Comments: 12 pages, 6 figures

Magnetic Activity-Rotation-Age-Mass Relations in Late Pre-main Sequence Stars [SSA]

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http://arxiv.org/abs/2305.09013


We study the four-dimensional relationships between magnetic activity, rotation, mass and age for solar-type stars in the age range 5-25Myr. This is the late-pre-main sequence (l-PMS) evolutionary phase when rapid changes in star’s interior may lead to the changes in magnetic dynamo mechanisms. We carefully derive rotational periods and spot sizes for 471 members of several l-PMS open clusters using photometric light curves from the Zwicky Transient Facility. Magnetic activity was measured in our previous Chandra-based study, and additional rotational data were obtained from other work. Several results emerge. Mass-dependent evolution of rotation through the l-PMS phase agrees with astrophysical models of stellar angular momentum changes, although the data point to a subpopulation of stars with slower initial rotations than commonly assumed. There is a hint of the onset of unsaturated tachoclinal dependency of X-ray activity on rotation, as reported by Argiroffi et al. (2016), but this result is not confidently confirmed. Both X-ray luminosity and star spot area decrease approximately as t^{-1} for solar mass stars suggesting that spot magnetic fields are roughly constant and l-PMS stars follow the universal solar-scaling law between the X-ray luminosity and surface magnetic flux. Assuming convective dynamos are dominant, theoretical magnetic fluxes fail to reveal the universal law for l-PMS stars that enter late Henyey tracks. Altogether we emerge with a few lines of evidence suggesting that the transition from the turbulent to solar-type dynamo occurs at the later stages of l-PMS evolution as stars approach the Zero-Age Main Sequence.

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K. Getman, E. Feigelson and G. Garmire
Wed, 17 May 23
52/67

Comments: 29 pages, 11 figures, 4 tables. Accepted for publication in The Astrophysical Journal, May 15, 2022

Dissipative Inflation via Scalar Production [CL]

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http://arxiv.org/abs/2305.07695


We describe a new mechanism that gives rise to dissipation during cosmic inflation. In the simplest implementation, the mechanism requires the presence of a massive scalar field with a softly-broken global $U(1)$ symmetry, along with the inflaton field. Particle production in this scenario takes place on parametrically sub-horizon scales, at variance with the case of dissipation into gauge fields. Consequently, the backreaction of the produced particles on the inflationary dynamics can be treated in a \textit{local} manner, allowing us to compute their effects analytically. We determine the parametric dependence of the power spectrum which deviates from the usual slow-roll expression. Non-Gaussianities are always sizeable whenever perturbations are generated by the noise induced by dissipation: $f_{\rm NL}^{\rm eq} \gtrsim {O}(10)$.

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P. Creminelli, S. Kumar, B. Salehian, et. al.
Tue, 16 May 23
6/83

Comments: 31 pages + appendices, 8 figures

Dynamics of false vacuum bubbles with trapped particles [CL]

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http://arxiv.org/abs/2305.07702


We study the impact of the ambient fluid on the evolution of collapsing false vacuum bubbles by simulating the dynamics of a coupled bubble-particle system. A significant increase in the mass of the particles across the bubble wall leads to a buildup of those particles inside the false vacuum bubble. We show that the backreaction of the particles on the bubble slows or even reverses the collapse. Consequently, if the particles in the true vacuum become heavier than in the false vacuum, the particle-wall interactions always decrease the compactness that the false vacuum bubbles can reach making their collapse to black holes less likely.

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M. Lewicki, K. Müürsepp, J. Pata, et. al.
Tue, 16 May 23
17/83

Comments: 13 pages, 7 figures

Extinction biases quasar luminosity distances determined from quasar UV and X-ray flux measurements [GA]

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http://arxiv.org/abs/2305.08179


A sample of X-ray detected reverberation-mapped quasars provides a unique opportunity to compare cosmological constraints inferred using two well-established relations – the X-ray/UV luminosity ($L_{X}-L_{UV}$) relation and the broad-line region radius-UV monochromatic luminosity ($R-L$) relation. $L_{X}-L_{UV}$ and $R-L$ luminosity distances to the same quasars exhibit a distribution of their differences that is generally positively skewed for the six cosmological models we consider. This behaviour can be interpreted qualitatively to arise as a result of the dust extinction of UV/X-ray quasar emission. We show that the extinction always contributes to the non-zero difference between $L_{X}-L_{UV}$-based and $R-L$-based luminosity distances and we derive a linear relationship between the X-ray/UV colour index $E_{X-UV}$ and the median/mean value of the luminosity-distance difference, which also depends on the value of the $L_{X}-L_{UV}$ relation slope. Taking into account the prevailing positive values of the luminosity-distance difference median, we estimate an average X-ray/UV colour index of $\overline{E}{X-UV}=0.089 \pm 0.019$ mag, while the value based on the positive mean values of the difference is $\overline{E}{X-UV}=0.050\pm 0.013$ mag. We demonstrate that this amount of extinction is typical for the majority of quasars since it originates in the circumnuclear and interstellar media of host galaxies. It can only be slightly alleviated by the standard hard X-ray and far-UV extinction cuts used by Lusso et al. (2020). Consequently, the $L_{X}-L_{UV}$ relation QSO data compilation of Lusso et al. (2020) cannot be used for cosmological purposes.

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M. Zajaček, B. Czerny, N. Khadka, et. al.
Tue, 16 May 23
19/83

Comments: 12 pages, 7 figures, 3 tables; submitted to the MNRAS Main Journal, comments welcome

Exploring Ultralight Scalar Assistance in Sterile Neutrino Dark Matter: Cold Spectrum and Unusual X/Gamma-ray Signatures [CL]

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http://arxiv.org/abs/2305.08095


We present a scalar-driven sterile neutrino production model where the interaction with the ultralight scalar field modifies the oscillation production of sterile neutrinos in the early universe. The model effectively suppresses the production of sterile neutrinos at low temperatures due to the heavy scalar mass, resulting in a colder matter power spectrum that avoids constraints from small-scale structure observations. In this model, the dominant dark matter relic is from sterile neutrinos, with only a small fraction originating from the ultralight scalar. Furthermore, the model predicts a detectable X/Gamma-ray flux proportional to the cubic density of local sterile neutrinos for a light scalar mass due to the light scalar coupling tosterile neutrinos. This distinguishes our model from normal decaying dark matter, which has a linear dependence on the density. In addition, the model predicts a potential low-energy monochromatic neutrino signal that can be detectable by future neutrino telescopes.

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Y. He, J. Liu, X. Ma, et. al.
Tue, 16 May 23
20/83

Comments: 15 pages, 5 figures

Two-body problem in theories with kinetic screening [CL]

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http://arxiv.org/abs/2305.07725


New light scalar degrees of freedom may alleviate the dark matter and dark energy problems, but if coupled to matter, they generally mediate a fifth force. In order for this fifth force to be consistent with existing constraints, it must be suppressed close to matter sources, e.g. through a non-linear screening mechanism. In this work, we investigate the non-relativistic two-body problem in shift-symmetric scalar-tensor theories that exhibit kinetic screening ($k$-mouflage), both numerically and analytically. We develop an approximate scheme, based on a Hodge-Helmholtz decomposition of the Noether current associated to the shift symmetry, allowing for a qualitative insight into the dynamics and yielding results in good agreement with the numerical ones in most of the parameter space. We apply the formalism to polynomial $k$-essence and to Dirac-Born-Infeld (DBI) type theories, as well as to theories that develop “anti-screening”. In the deep nonlinear regime, we find that the fifth force is screened slightly more efficiently in equal-mass systems than in extreme mass-ratio ones. However, we find that systems with comparable masses also exhibit regions where the screening is ineffective. These descreened spheroidal regions (bubbles) could in principle be probed in the solar system with sufficiently precise space accelerometers.

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M. Bošković and E. Barausse
Tue, 16 May 23
28/83

Comments: 16+5 pages; 13 figures

Pulsar timing residual induced by ultralight tensor dark matter [CL]

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http://arxiv.org/abs/2305.08091


Ultralight boson fields, with a mass around $10^{-23}\text{eV}$, are promising candidates for the elusive cosmological dark matter. These fields induce a periodic oscillation of the spacetime metric in the nanohertz frequency band, which is detectable by pulsar timing arrays. In this paper, we investigate the gravitational effect of ultralight tensor dark matter on the arrival time of radio pulses from pulsars. We find that the pulsar timing signal caused by tensor dark matter exhibits a different angular dependence than that by scalar and vector dark matter, making it possible to distinguish the ultralight dark matter signal with different spins. Combining the gravitational effect and the coupling effect of ultralight tensor dark matter with standard model matter provides a complementary way to constrain the coupling parameter $\alpha$. We estimate $\alpha \lesssim 10^{-6}\sim 10^{-5}$ in the mass range $m<5\times 10^{-23}\mathrm{eV}$ with current pulsar timing array.

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Y. Wu, Z. Chen and Q. Huang
Tue, 16 May 23
45/83

Comments: 12 pages, 3 figures

Resolving phase transition properties of dense matter through tidal-excited g-mode from inspiring neutron stars [CL]

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http://arxiv.org/abs/2305.08401


The investigation of the phase state of dense matter is hindered by complications of first-principle nonperturbative quantum chromodynamics. By performing the first consistent general-relativistic calculations of tidal-excited g-mode of neutron stars with a first-order strong interaction phase transition in the high-density core, we demonstrate that gravitational wave signal during binary neutron star inspiral probes their innermost hadron-quark transition and provides potent constraints from present and future gravitational-wave detectors.

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Z. Miao, E. Zhou and A. Li
Tue, 16 May 23
51/83

Comments: 5 pages, 3 figures, 6 pages supplemental material

Is Cosmic Birefringence model-dependent? [CEA]

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http://arxiv.org/abs/2305.07937


Exciting clues to isotropic cosmic birefringence have recently been detected in the $EB$ cross-power spectra of the polarization data of the cosmic microwave background (CMB). Early Dark Energy (EDE) models with a pseudoscalar field coupled to photons via a Chern-Simons term can be used to explain this phenomenon, and can also potentially be used to simultaneously resolve the $H_0$ tension. In this work we incorporate an early dark energy scalar field, including a Chern-Simons coupling, into an existing Boltzmann solver and numerically recover the $EB$ cross-power spectrum for two models in the literature; the $\alpha$-attractor, and the Rock `n’ Roll field. We find that both the models fit the $EB$ spectra, and the $EB$ spectra alone do not possess sufficient constraining power to distinguish the two models based on current data.

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L. Yin, J. Kochappan, T. Ghosh, et. al.
Tue, 16 May 23
60/83

Comments: N/A

Neutrino forces and experimental probes [CL]

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http://arxiv.org/abs/2305.08032


Neutrinos as almost massless particles could mediate long-range forces, known as neutrino forces. In this talk, I will introduce some theoretical aspects of neutrino forces, including why the potential of a neutrino force has the $1/r^{5}$ form and how it may vary under different circumstances. Experimental probes and possible implications for cosmology are also briefly discussed.

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X. Xu
Tue, 16 May 23
74/83

Comments: 6 pages, 4 figures, Contribution to the 2023 Electroweak session of the 57th Rencontres de Moriond

Abelian-Higgs cosmic strings: effective action and particle radiation [CL]

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http://arxiv.org/abs/2305.08155


We utilized the duality between massive vector and massive Kalb-Ramond fields to derive an effective action for Abelian-Higgs cosmic strings. This enabled us to determine the classically renormalized string tension and facilitate calculations for back-reaction effects. Additionally, we derived a comprehensive expression for the energy flux of radiation emitted by Abelian-Higgs cosmic strings. Applying this equation to a cuspless loop, we obtained that the loop lifetime is proportional to the square of the loop length, which is in agreement with field-theory simulations.

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I. Rybak
Tue, 16 May 23
77/83

Comments: 14 pages, 1 figure

Identifying Extended PeVatron Sources via Neutrino Shower Detection [HEAP]

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http://arxiv.org/abs/2305.07043


Identifying the Milky Way’s very high energy hadronic cosmic-ray accelerators — the PeVatrons — is a critical problem. While gamma-ray observations reveal promising candidate sources, neutrino detection is needed for certainty, and this has not yet been successful. Why not? There are several possibilities, as we delineated in a recent paper [T. Sudoh and J. F. Beacom, Phys. Rev. D 107, 043002 (2023)]. Here we further explore the possibility that the challenges arise because PeVatrons have a large angular extent, either due to cosmic-ray propagation effects or due to clusters of sources. We show that while extended neutrino sources could be missed in the commonly used muon-track channel, they could be discovered in the all-flavor shower channel, which has a lower atmospheric-neutrino background flux per solid angle. Intrinsically, showers are quite directional and would appear so in water-based detectors like the future KM3NeT, even though they are presently badly smeared by light scattering in ice-based detectors like IceCube. Our results motivate new shower-based searches as part of the comprehensive approach to identifying the Milky Way’s hadronic PeVatrons.

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T. Sudoh and J. Beacom
Mon, 15 May 23
7/53

Comments: Main text 9 pages, 5 figures. Comments are welcome

Insights from HST into Ultra-Massive Galaxies and Early-Universe Cosmology [CEA]

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http://arxiv.org/abs/2305.07049


The early-science observations made by the James Webb Space Telescope (JWST) have revealed an excess of ultra-massive galaxy candidates that appear to challenge the standard cosmological model ($\Lambda$CDM). Here, we argue that any modifications to $\Lambda$CDM that can produce such ultra-massive galaxies in the early Universe would also affect the UV galaxy luminosity function (UV LF) inferred from the Hubble Space Telescope (HST). The UV LF covers the same redshifts ($z\approx 7-10$) and host-halo masses $(M_\mathrm{h}\approx 10^{10}-10^{12}\, M_\odot$) as the JWST candidates, but tracks star-formation rate rather than stellar mass. We consider beyond-$\Lambda$CDM power-spectrum enhancements and show that any departure large enough to reproduce the abundance of ultra-massive JWST candidates is in conflict with the HST data. Our analysis, therefore, severely disfavors a cosmological explanation for the JWST abundance problem. Looking ahead, we determine the maximum allowable stellar-mass function and provide projections for the high-$z$ UV LF given our constraints on cosmology from current HST data.

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N. Sabti, J. Muñoz and M. Kamionkowski
Mon, 15 May 23
22/53

Comments: 9 pages, 4 figures

Probing the Origin of Primordial Black Holes through Novel Gravitational Wave Spectrum [CL]

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http://arxiv.org/abs/2305.07569


In this article we investigate the cumulative stochastic gravitational wave spectra as a tool to gain insight on the creation mechanism of primordial black holes. We consider gravitational waves from the production mechanism of primordial black holes and from the gravitational interactions of those primordial black holes among themselves and other astrophysical black holes. We specifically focus on asynchronous bubble nucleation during a first order phase transition as the creation mechanism. We have used two benchmark phase transitions through which the primordial black holes and the primary gravitational wave spectra have been generated. We have considered binary systems and close hyperbolic interactions of primordial black holes with other primordial and astrophysical black holes as the source of the secondary part of the spectra. We have shown that this unique cumulative spectra have features which directly and indirectly depend on the specifics of the production mechanism.

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I. Banerjee and U. Dey
Mon, 15 May 23
35/53

Comments: 22 pages, 9 figures, 2 tables

First-order phase transitions in Yang-Mills theories and the density of state method [CL]

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http://arxiv.org/abs/2305.07463


When studied at finite temperature, Yang-Mills theories in $3+1$ dimensions display the presence of confinement/deconfinement phase transitions, which are known to be of first order — the $SU(2)$ gauge theory being the exception. Theoretical as well as phenomenological considerations indicate that it is essential to establish a precise characterisation of these physical systems in proximity of such phase transitions. We present and test a new method to study the critical region of parameter space in non-Abelian quantum field theories on the lattice, based upon the Logarithmic Linear Relaxation (LLR) algorithm. We apply this method to the $SU(3)$ Yang Mills lattice gauge theory, and perform extensive calculations with one fixed choice of lattice size. We identify the critical temperature, and measure interesting physical quantities near the transition. Among them, we determine the free energy of the model in the critical region, exposing for the first time its multi-valued nature with a numerical calculation from first principles, providing this novel evidence in support of a first order phase transition. This study sets the stage for future high precision measurements, by demonstrating the potential of the method.

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B. Lucini, D. Mason, M. Piai, et. al.
Mon, 15 May 23
48/53

Comments: 25 pages, 21 figures

A Leptonic Model for Neutrino Emission From Active Galactic Nuclei [HEAP]

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http://arxiv.org/abs/2305.06375


It is often stated that the observation of high-energy neutrinos from an astrophysical source would constitute a smoking gun for the acceleration of hadronic cosmic rays. Here, we point out that there exists a purely leptonic mechanism to produce TeV-scale neutrinos in astrophysical environments. In particular, very high energy synchrotron photons can scatter with X-rays, exceeding the threshold for muon-antimuon pair production. When these muons decay, they produce neutrinos without any cosmic-ray protons or nuclei being involved. In order for this mechanism to be efficient, the source in question must feature both kG-scale magnetic fields and a high density of keV-scale photons. As an example, we consider the active galaxy NGC 1068, which IceCube has recently detected as a source of TeV-scale neutrinos. We find that the neutrino emission observed from this source could potentially be generated through muon pair production for reasonable choices of physical parameters.

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D. Hooper and K. Plant
Fri, 12 May 23
18/53

Comments: 4 pages, 2 figures

Twin Sterile Neutrino Dark Matter [CL]

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http://arxiv.org/abs/2305.06364


We propose that the dark matter of our universe could be sterile neutrinos which reside within the twin sector of a mirror twin Higgs model. In our scenario, these particles are produced through a version of the Dodelson-Widrow mechanism that takes place entirely within the twin sector, yielding a dark matter candidate that is consistent with X-ray and gamma-ray line constraints. Furthermore, this scenario can naturally avoid the cosmological problems that are typically encountered in mirror twin Higgs models. In particular, if the sterile neutrinos in the Standard Model sector decay out of equilibrium, they can heat the Standard Model bath and reduce the contributions of the twin particles to $N_\mathrm{eff}$. Such decays also reduce the effective temperature of the dark matter, thereby relaxing constraints from large-scale structure. The sterile neutrinos included in this model are compatible with the seesaw mechanism for generating Standard Model neutrino masses.

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I. Holst, D. Hooper, G. Krnjaic, et. al.
Fri, 12 May 23
23/53

Comments: N/A

Constraining Primordial Magnetic Fields with Line-Intensity Mapping [CEA]

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http://arxiv.org/abs/2305.06440


Primordial magnetic fields (PMFs) offer a compelling explanation for the origin of observed magnetic fields, especially on extragalactic scales. Such PMFs give rise to excess of power in small scale matter perturbations that could strongly influence structure formation. We study the impact of the magnetically enhanced matter power spectrum on the signal that will be observed by line-intensity mapping (LIM) surveys targeting carbon monoxide (CO) emission from star-forming galaxies at high redshifts. Specifically, the voxel intensity distribution of intensity maps provides access to small-scale information, which makes it highly sensitive to signatures of PMFs on matter overdensities. We present forecasts for future LIM CO surveys, finding that they can constrain PMF amplitudes as small as $\sigma_{B,0}\sim0.04-1\,{\rm nG}$, depending on the magnetic spectral index and the targeted redshifts.

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T. Adi, S. Libanore, H. Cruz, et. al.
Fri, 12 May 23
29/53

Comments: 9 pages, 3 figures, 2 tables

Flavor-dependent long-range neutrino interactions in DUNE & T2HK: alone they constrain, together they discover [CL]

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http://arxiv.org/abs/2305.05184


Discovering new neutrino interactions would represent evidence of physics beyond the Standard Model. We focus on new flavor-dependent long-range neutrino interactions mediated by ultra-light mediators, with masses below $10^{-10}$ eV, introduced by new lepton-number gauge symmetries $L_e-L_\mu$, $L_e-L_\tau$, and $L_\mu-L_\tau$. Because the interaction range is ultra-long, nearby and distant matter – primarily electrons and neutrons – in the Earth, Moon, Sun, Milky Way, and the local Universe, may source a large matter potential that modifies neutrino oscillation probabilities. The upcoming Deep Underground Neutrino Experiment (DUNE) and the Tokai-to-Hyper-Kamiokande (T2HK) long-baseline neutrino experiments will provide an opportunity to search for these interactions, thanks to their high event rates and well-characterized neutrino beams. We forecast their probing power. Our results reveal novel perspectives. Alone, DUNE and T2HK may strongly constrain long-range interactions, setting new limits on their coupling strength for mediators lighter than $10^{-18}$ eV. However, if the new interactions are subdominant, then both DUNE and T2HK, together, will be needed to discover them, since their combination lifts parameter degeneracies that weaken their individual sensitivity. DUNE and T2HK, especially when combined, provide a valuable opportunity to explore physics beyond the Standard Model.

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M. Singh, M. Bustamante and S. Agarwalla
Thu, 11 May 23
8/55

Comments: 35 pages, 12 figures, 7 tables, 4 appendices. Comments are welcome

On unitarity in Higgs-like inflation [CL]

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http://arxiv.org/abs/2305.05682


We study inflationary models based on a non-minimal coupling of a singlet scalar to gravity, focussing on the preheating dynamics and the unitarity issues in this regime. If the scalar does not have significant couplings to other fields, particle production after inflation is far less efficient than that in Higgs inflation. As a result, unitarity violation at large non-minimal couplings requires a different treatment. We find that collective effects in inflaton scattering processes during preheating make an important impact on the unitarity constraint. Within effective field theory, the consequent upper bound on the non-minimal coupling is of order a few hundreds.

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O. Lebedev, Y. Mambrini and J. Yoon
Thu, 11 May 23
12/55

Comments: N/A

Absorption of Axion Dark Matter in a Magnetized Medium [CL]

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http://arxiv.org/abs/2305.05681


Detection of axion dark matter heavier than a meV is hindered by its small wavelength, which limits the useful volume of traditional experiments. This problem can be avoided by directly detecting in-medium excitations, whose $\sim \text{meV} – \text{eV}$ energies are decoupled from the detector size. We show that for any target inside a magnetic field, the absorption rate of electromagnetically-coupled axions into in-medium excitations is determined by the dielectric function. As a result, the plethora of candidate targets previously identified for sub-GeV dark matter searches can be repurposed as broadband axion detectors. We find that a $\text{kg} \cdot \text{yr}$ exposure with noise levels comparable to recent measurements is sufficient to probe parameter space currently unexplored by laboratory tests. Noise reduction by only a few orders of magnitude can enable sensitivity to the QCD axion in the $\sim 10 \ \text{meV} – 10 \ \text{eV}$ mass range.

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A. Berlin and T. Trickle
Thu, 11 May 23
47/55

Comments: 10 pages, 2 figures

Possible hints of decreasing dark energy from supernova data [CEA]

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http://arxiv.org/abs/2305.04946


The potential energy from a time-dependent scalar field provides a possible explanation for the observed cosmic acceleration. In this paper, we investigate how the redshift vs brightness data from the recent Pantheon+ survey of type Ia supernovae constrain the possible evolution of a single scalar field for the period of time (roughly half the age of the universe) over which supernova data are available. Taking a linear approximation to the potential, we find that models providing a good fit to the data typically have a decreasing potential energy at present (accounting for over 99% of the allowed parameter space) with a significant variation in scalar potential ($\langle {\rm Range}(V)/V_0 \rangle \approx 0.97$) over the period of time corresponding to the available data ($z < 2.3$). Including quadratic terms in the potential, the data can be fit well for a wide range of possible potentials including those with positive or negative $V_2$ of large magnitude, and models where the universe has already stopped accelerating. We describe a few degeneracies and approximate degeneracies in the model that help explain the somewhat surprising range of allowed potentials.

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M. Raamsdonk and C. Waddell
Wed, 10 May 23
18/65

Comments: N/A

Primordial Black Holes from Supercooled Phase Transitions [CL]

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http://arxiv.org/abs/2305.04942


Cosmological first-order phase transitions (1stOPTs) are said to be strongly supercooled when the nucleation temperature is much smaller than the critical temperature. These are often encountered in theories that admit a nearly scale-invariant potential, for which the bounce action decreases only logarithmically with temperature. During supercooled 1stOPTs the equation of state of the universe undergoes a rapid and drastic change, transitioning from vacuum-domination to radiation-domination. The statistical variations in bubble nucleation histories imply that distinct causal patches percolate at slightly different times. Patches which percolate the latest undergo the longest vacuum-domination stage and as a consequence develop large over-densities triggering their collapse into primordial black holes (PBHs). We derive an analytical approximation for the probability of a patch to collapse into a PBH as a function of the 1stOPT duration, $\beta^{-1}$, and deduce the expected PBH abundance. We find that 1stOPTs which take more than $12\%$ of a Hubble time to complete ($\beta/H \lesssim 8$) produce observable PBHs. Their abundance is independent of the duration of the supercooling phase, in agreement with the de Sitter no hair conjecture.

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Y. Gouttenoire and T. Volansky
Wed, 10 May 23
19/65

Comments: Main text: 6 pages, 5 figures, Appendices: 12 pages, 6 figures

R-modes as a New Probe of Dark Matter in Neutron Stars [HEAP]

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http://arxiv.org/abs/2305.05664


In this work, we perform the first systematic investigation of effects of the presence of dark matter on r-mode oscillations in neutron stars (NSs). Using a self-interacting dark matter (DM) model based on the neutron decay anomaly and a hadronic model obtained from the posterior distribution of a recent Bayesian analysis, we impose constraints on the DM self-interaction strength using recent multimessenger astrophysical observations. The constrained DM interaction strength is then used to estimate DM self-interaction cross section and shear viscosity resulting from DM, which is found to be several orders of magnitude smaller than shear viscosity due to hadronic matter. Assuming that the DM fermion is in chemical equilibrium with the neutrons in the neutron star, we estimate the bulk viscosity resulting from the dark decay of neutrons, and find it to be much smaller than the hadronic bulk viscosity. We also conclude that the instability window with minimal hadronic damping mechanisms can become smaller when including DM shear and bulk viscosity but remains incompatible with the X-ray and pulsar observational data for the chosen DM model.

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S. Shirke, S. Ghosh, D. Chatterjee, et. al.
Wed, 10 May 23
34/65

Comments: 29 pages, 12 figures, 1 table. To be submitted to JCAP. Comments are welcome

Constraining $p$-wave Dark Matter Annihilation with Gamma-ray Observations of M87 [CL]

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http://arxiv.org/abs/2305.05155


We consider constraints on $p$-wave dark matter in a dark matter spike surrounding the supermassive black hole at the center of M87. Owing to the large mass of the black hole, and resulting large velocity dispersion for the dark matter particles in the spike, it is possible for Fermi-LAT and MAGIC data to place tight constraints on $p$-wave annihilation, which would be far more stringent than those placed by observations of dwarf spheroidal galaxies. Indeed, for optimistic choices of the spike parameters, gamma-ray data would exclude thermal $p$-wave dark matter models with a particle mass $\lesssim {10}~\rm TeV$. But there is significant uncertainty in the properties and parameters of the spike, and for less optimistic scenarios, thermal dark matter candidates would be completely unconstrained. In addition to better understanding the spike parameters, a second key to improving constraints on dark matter annihilation is an accurate astrophysical background model.

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K. Christy, J. Kumar and P. Sandick
Wed, 10 May 23
47/65

Comments: 10 pages, 4 figures

Accurate electron-recoil ionization factors for dark matter direct detection in xenon, krypton and argon [CL]

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http://arxiv.org/abs/2305.05125


While most scintillation-based dark matter experiments search for Weakly Interacting Massive Particles (WIMPs), a sub-GeV WIMP-like particle may also be detectable in these experiments. While dark matter of this type and scale would not leave appreciable nuclear recoil signals, it may instead induce ionization of atomic electrons. Accurate modelling of the atomic wavefunctions is key to investigating this possibility, with incorrect treatment leading to a large suppression in the atomic excitation factors. We have calculated these atomic factors for argon, krypton and xenon and present the tabulated results for use with a range of dark matter models. This is made possible by the separability of the atomic and dark matter form factor, allowing the atomic factors to be calculated for general couplings; we include tables for vector, scalar, pseudovector, and pseudoscalar electron couplings. Additionally, we calculate electron impact total ionization cross sections for xenon using the tabulated results as a test of accuracy. Lastly, we provide an example calculation of the event rate for dark matter scattering on electrons in XENON1T and show that these calculations depend heavily on how the low-energy response of the detector is modelled.

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A. Caddell, V. Flambaum and B. Roberts
Wed, 10 May 23
51/65

Comments: N/A

GRB 221009A: Spectral signatures based on ALPs candidates [HEAP]

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http://arxiv.org/abs/2305.05145


GRB 221009A has posed a significant challenge to our current understanding of the mechanisms that produce TeV photons in gamma-ray bursts (GRB). On one hand, the Klein-Nishina (KN) effect of the inverse Compton scattering leads to less efficient energy losses of high-energy electrons. In the other hand, at a redshift of 0.151, the TeV spectrum of GRB 221009A undergoes significant absorption by the Extragalactic Background Light (EBL). Therefore, the observation of 18-TeV and 250-TeV photons in this event implies the presence of enormous photon fluxes at the source, which cannot be easily generated by the Synchrotron Self-Compton mechanism in external shocks. As an alternative, some authors have suggested the possibility of converting the TeV-photons into Axion-like particles (ALPs) at the host galaxy, in order to avoid the effects of EBL absorption, and then reconverting them into photons within the Milky Way. While this solution relaxes the requirement of very-high photon fluxes, the KN effect still poses a challenge. Previously, we have showed that the injections of ALPs could explain the observation of 18-TeV photons. Here, we include the energy dependence of the survival probability to determine the spectral conditions that would be required for the injection of such ALPs, limit the ALP’s candidate region, and discuss the implications in the maximum particle rate for different light-curve assumptions.

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D. Rojas, S. Hernández-Cadena, M. González, et. al.
Wed, 10 May 23
65/65

Comments: N/A

IceCube and the origin of ANITA-IV events [HEAP]

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http://arxiv.org/abs/2305.03746


Recently, the ANITA collaboration announced the detection of new, unsettling upgoing Ultra-High-Energy (UHE) events. Understanding their origin is pressing to ensure success of the incoming UHE neutrino program. In this work, we study their internal consistency and the implications of the lack of similar events in IceCube. We introduce a generic, simple parametrization to study the compatibility between these two observatories in Standard Model-like and Beyond Standard Model scenarios: an incoming flux of particles that interact with Earth nucleons with cross section $\sigma$, producing particle showers along with long-lived particles that decay with lifetime $\tau$ and generate a shower that explains ANITA observations. We find that the ANITA angular distribution imposes significant constraints, and when including null observations from IceCube only $\tau \sim 10^{-3}$ – $10^{-2} \,\mathrm{s}$ and $\sigma \sim 10^{-33}$ – $10^{-32}\,\mathrm{cm^2}$ can explain the data. This hypothesis is testable with future IceCube data. Finally, we discuss a specific model that can realize this scenario. Our analysis highlights the importance of simultaneous observations by high-energy optical neutrino telescopes and new UHE radio detectors to uncover cosmogenic neutrinos or discover new physics.

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T. Bertólez-Martínez, C. Argüelles, I. Esteban, et. al.
Tue, 9 May 23
24/88

Comments: 11 pages, 7 figures + Appendices. Comments welcome!

ALP dark matter with non-periodic potentials: parametric resonance, halo formation and gravitational signatures [CL]

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http://arxiv.org/abs/2305.03756


Axion-like particles (ALPs) are leading candidates to explain the dark matter in the universe. Their production via the misalignment mechanism has been extensively studied for cosine potentials characteristic of pseudo-Nambu-Goldstone bosons. In this work we investigate ALPs with non-periodic potentials, which allow for large misalignment of the field from the minimum. As a result, the ALP can match the relic density of dark matter in a large part of the parameter space. Such potentials give rise to self-interactions which can trigger an exponential growth of fluctuations in the ALP field via parametric resonance, leading to the fragmentation of the field. We study these effects with both Floquet analysis and lattice simulations. Using the Press-Schechter formalism, we predict the halo mass function and halo spectrum arising from ALP dark matter. These halos can be dense enough to produce observable gravitational effects such as astrometric lensing, diffraction of gravitational wave signals from black hole mergers, photometric microlensing of highly magnified stars, perturbations of stars in the galactic disk or stellar streams. These effects would provide a probe of dark matter even if it does not couple to the Standard Model. They would not be observable for halos predicted for standard cold dark matter and for ALP dark matter in the standard misalignment mechanism. We determine the relevant regions of parameter space in the (ALP mass, decay constant)-plane and compare predictions in different axion fragmentation models.

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A. Chatrchyan, C. Eröncel, M. Koschnitzke, et. al.
Tue, 9 May 23
29/88

Comments: 49 pages and 22 figures in the main text, and 14 pages and 2 figures in appendices

Weakly-Supervised Anomaly Detection in the Milky Way [GA]

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http://arxiv.org/abs/2305.03761


Large-scale astrophysics datasets present an opportunity for new machine learning techniques to identify regions of interest that might otherwise be overlooked by traditional searches. To this end, we use Classification Without Labels (CWoLa), a weakly-supervised anomaly detection method, to identify cold stellar streams within the more than one billion Milky Way stars observed by the Gaia satellite. CWoLa operates without the use of labeled streams or knowledge of astrophysical principles. Instead, we train a classifier to distinguish between mixed samples for which the proportions of signal and background samples are unknown. This computationally lightweight strategy is able to detect both simulated streams and the known stream GD-1 in data. Originally designed for high-energy collider physics, this technique may have broad applicability within astrophysics as well as other domains interested in identifying localized anomalies.

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M. Pettee, S. Thanvantri, B. Nachman, et. al.
Tue, 9 May 23
48/88

Comments: N/A

Generalized Linear Models of T$_{90}$-T$_{50}$ relation to classify GRBs [HEAP]

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http://arxiv.org/abs/2305.03947


Gamma-ray bursts (GRBs) can be classified with their linearly dependent parameters alongside the standard $T_{90}$ distribution. The Generalized linear mixture model(GLM) identifies the number of linear dependencies in a two-parameter space. Classically, GRBs are classified into two classes by the presence of bimodality in the histogram of T${90}$. However, additional classes and sub-classes of GRBs are fascinating topics to explore. In this work, we investigate the GRBs classes in the $ T{90} {-}T_{50}$ plane using the Generalized Linear Models(GLM) for \textit{Fermi} GBM and BATSE catalogs. This study shows five linear features for the \textit{Fermi} GBM catalog and four linear features for the BATSE catalog, directing towards the possibility of more than two GRB classes.

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S. Dutta, S. Sunanda, R. Moharana, et. al.
Tue, 9 May 23
49/88

Comments: 8 figures, 1 table

Strong-Field Physics in QED and QCD: From Fundamentals to Applications [CL]

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http://arxiv.org/abs/2305.03865


We provide a pedagogical review article on fundamentals and applications of the quantum dynamics in strong electromagnetic fields in QED and QCD. The fundamentals include the basic picture of the Landau quantization and the resummation techniques applied to the class of higher-order diagrams that are enhanced by large magnitudes of the external fields. We then discuss observable effects of the vacuum fluctuations in the presence of the strong fields, which consist of the interdisciplinary research field of nonlinear QED. We also discuss extensions of the Heisenberg-Euler effective theory to finite temperature/density and to non-Abelian theories with some applications. Next, we proceed to the paradigm of the dimensional reduction emerging in the low-energy dynamics in the strong magnetic fields. The mechanisms of superconductivity, the magnetic catalysis of the chiral symmetry breaking, and the Kondo effect are addressed from a unified point of view in terms of the renormalization-group method. We provide an up-to-date summary of the lattice QCD simulations in magnetic fields for the chiral symmetry breaking and the related topics as of the end of 2022. Finally, we discuss novel transport phenomena induced by chiral anomaly and the axial-charge dynamics. Those discussions are supported by a number of appendices.

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K. Hattori, K. Itakura and S. Ozaki
Tue, 9 May 23
53/88

Comments: Prepared for an invited review article

Phenomenology of wavelike vector dark matter nonminimally coupled to gravity [CEA]

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http://arxiv.org/abs/2305.03841


We study three astrophysical/cosmological consequences of nonminimal couplings to gravity in wavelike vector dark matter. In the nonrelativistic limit, the nonminimal coupling with the lowest mass dimension leads to effective self-interactions that affect the mass-radius relation of vector solitons, growth of linear perturbations during structure formation, and the speed of gravitational waves (GWs). Based on the success of cold dark matter on large-scale perturbations and the current limits on GW speed, we constrain the dark matter mass and nonminimal coupling strength to be within the range $|\xi_1| / m^2 \ll 10^{50} \mathrm{eV^{-2}}$ and $-3\times 10^{46} \mathrm{eV^{-2}} \lesssim \xi_2 / m^2 \lesssim 8 \times 10^{48} \mathrm{eV^{-2}}$.

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H. Zhang and S. Ling
Tue, 9 May 23
56/88

Comments: 13 pages + appendices, 2 figures

Primordial black holes from strong first-order phase transitions [CEA]

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http://arxiv.org/abs/2305.04924


We study the formation of primordial black holes (PBHs) in strongly supercooled first-order phase transitions. The mechanism is based on the presence of remnants dominated by the false vacuum that scale slower with the expansion of the Universe than their surroundings where this energy was already converted into radiation. We compute the PBH formation from these remnants including the contribution from the false vacuum and the bubble walls, by estimating the collapse using the hoop conjecture and by considering both regions collapsing immediately when entering the horizon and sub-horizon regions that collapse as their compactness grows. We show that for exponential bubble nucleation rate, $\Gamma \propto e^{\beta t}$, the primordial black hole formation implies $\beta/H \gtrsim 3.8$, where $H$ denotes the Hubble rate, if the potential energy of the false vacuum is $\Delta V \lesssim (10^{12} {\rm GeV})^4$, as otherwise a too large abundance of long-lived PBHs forms. The observed dark matter abundance can be formed in asteroid mass PBHs if $\beta/H \simeq 3.8$ and $10^5 {\rm GeV} \lesssim \Delta V^{1/4} \lesssim 10^8 {\rm GeV}$. Finally, we consider also the effect of the second order correction to the exponential nucleation rate showing that the PBH abundance is mainly determined by the average radius of the true vacuum bubbles.

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M. Lewicki, P. Toczek and V. Vaskonen
Tue, 9 May 23
65/88

Comments: 15 pages, 6 figures

Exploring the viability of pseudo Nambu-Goldstone boson as ultralight dark matter in a mass range relevant for strong gravity applications [CL]

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http://arxiv.org/abs/2305.03776


We study a simple extension of the Standard Model featuring a dark sector with an ultralight pseudo Nambu-Goldstone boson as dark matter candidate. We focus on the mass range $\mathcal{O}(10^{-20} – 10^{-10})$ eV, relevant for strong gravity applications, and explore its production and evolution in the early Universe. The model is formulated in such a way that dark matter does not couple directly to photons or other Standard Model particles avoiding some of the most stringent cosmological bounds related to axion-like particles. In this work, two different scenarios are considered depending on whether dark matter is produced in a pre-inflationary or post-inflationary regime. We also discuss the effect from emergent topological defects such as cosmic strings and domain walls, and estimate the spectrum of stochastic gravitational waves produced by their decay, enabling to test the model at current and future gravitational-wave experiments.

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A. Morais, V. Oliveira, A. Onofre, et. al.
Tue, 9 May 23
72/88

Comments: 22 pages, 5 figures

New Horizons in the Holographic Conformal Phase Transition [CL]

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http://arxiv.org/abs/2305.03773


We describe cosmological solutions of the holographic dilaton with the aim of exploring alternatives to the commonly studied thermal Randall-Sundrum phase transition. It is well known that the thermal transition is typically strongly first order, with the requirement of a perturbative 5D gravity theory obstructing completion of the transition. This thermal transition corresponds to nucleation of an infrared brane through the surface of an AdS-Schwarzschild horizon. The approach we study instead invokes an early epoch in which the cosmology is fully 5-dimensional, with highly relativistic brane motion, and with Rindler horizons obscuring the infrared brane at early times. Our approach corresponds, via AdS/CFT, to a non-equilibrium approach to the conformal phase transition. We comment on a class of initial conditions that generically leads to completion of the phase transition without sacrificing perturbativity of the 5D theory.

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C. Eröncel, J. Hubisz, S. Lee, et. al.
Tue, 9 May 23
82/88

Comments: 43 pages, 9 figures

Spectral distortions of astrophysical blackbodies as axion probes [CL]

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http://arxiv.org/abs/2305.03749


Recent studies reveal that more than a dozen of white dwarfs displaying near-perfect blackbody spectra in the optical range have been lurking in the Sloan Digital Sky Survey catalog. We point out that, in a way analogous to the Cosmic Microwave Background, these stars serve as excellent testbeds for new physics. Specifically, we show how their observed lack of spectral distortions translates into limits on the parameter space of axions with electromagnetic coupling. The prospects for future improvements are also discussed.

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J. Chang, R. Ebadi, X. Luo, et. al.
Tue, 9 May 23
85/88

Comments: 14 pages, 8 figures

Neutrino many-body correlations [CL]

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http://arxiv.org/abs/2305.04916


This paper responds to suggestions that the standard approach to collective neutrino oscillations leaves out potentially important quantum many-body correlations. Arguments in favor of this idea have been based on calculations that, on close scrutiny, offer no evidence either way. Inadequacies of the usual quantum-kinetic formalism are not currently supported by the literature.

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L. Johns
Tue, 9 May 23
86/88

Comments: 8 pages, 0 figures

Cosmic rays from heavy particle decays [CL]

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http://arxiv.org/abs/2305.03313


Multidimensional modification of gravity with a smaller mass scale of the gravitational interaction is considered. Stable by assumption dark matter particles could decay via interactions with virtual black holes. The decay rates of such processes are estimated. It is shown that with the proper fixation of the parameters the decays of these ultra-massive particles can give noticeable contribution to the flux of high energy cosmic rays in particular, near the Greisen-Zatsepin-Kuzmin limit. Such particles can also create neutrinos of very high energies observed in the existing huge underwater or ice-cube detectors.

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E. Arbuzova, A. Dolgov and A. Nikitenko
Mon, 8 May 23
12/63

Comments: 7 pages, 3 figures

One loop to rule them all: Perturbativity in the presence of ultra slow-roll dynamics [CEA]

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http://arxiv.org/abs/2305.03491


We discuss the issue of perturbativity in single-field inflationary models with a phase of ultra slow-roll (USR) tailor suited to generate an order-one abundance of primordial black holes (PBHs). More in detail, we impose the condition that loop corrections made up of short-wavelength modes enhanced by the USR dynamics do not alter the tree-level power spectrum of curvature perturbations. In our analysis, the USR phase is preceded and followed by two stages of ordinary slow-roll (SR), and we model the resulting SR/USR/SR dynamics using both instantaneous and smooth transitions. Focusing on scales relevant for CMB observations, we find that it is not possible, with these arguments, to rule out the scenario of PBH formation via USR, not even in the limit of instantaneous transition. However, we also find that loop corrections of short modes on the power spectrum of long modes, even though not large enough to violate perturbativity requirements, remain appreciable and, most importantly, are not tamed in realistic realisations of smooth SR/USR/SR transitions. This makes perturbativity a powerful theoretical tool to constrain USR dynamics. We extend the analysis at any scale beyond those relevant for CMB observations. We find that loop corrections of short modes remain within the few percent if compared to the tree-level power spectrum. However, we also find one notable exception of phenomenological relevance: we show that the so-called dip in the power spectrum of curvature perturbation is an artifact of the tree-level computation.

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G. Franciolini, A. Iovino, M. Taoso, et. al.
Mon, 8 May 23
14/63

Comments: 31 pages, 12 figures

Dark Matter-Induced Stellar Oscillations [CL]

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http://arxiv.org/abs/2305.03085


It has been hypothesized that dark matter is comprised of ultra-light bosons whose collective phenomena can be described as a scalar field undergoing coherent oscillations. Examples include axion and fuzzy dark matter models. In this ultra-light dark matter scenario, the harmonic variation in the field’s energy-momentum tensor sources an oscillating component of the gravitational potential that we show can resonantly-excite stellar oscillations. A mathematical framework for predicting the amplitude of these oscillations is developed, which reveals that ultra-light dark matter predominantly excites p-modes of degree $l=1$. An investigation of resonantly-excited solar oscillations is presented, from which we conclude that dark matter-induced oscillations of the Sun are likely undetectable. We discuss prospects for constraining ultra-light dark matter using other stellar objects.

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J. Sakstein and I. Saltas
Mon, 8 May 23
25/63

Comments: 5 pages, no figures. Comments welcome. A reproduction package for our numerical analysis is available here: this https URL

Tip of the Red Giant Branch Bounds on the Axion-Electron Coupling Revisited [CL]

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http://arxiv.org/abs/2305.03113


We present a novel method to constrain the axion-electron coupling constant using the observed calibration of the tip of the red giant branch (TRGB) I band magnitude $M_I$ that fully accounts for uncertainties and degeneracies with stellar input physics.~We simulate a grid of 116,250 models varying initial mass, helium abundance, and metallicity and train a machine learning emulator to predict $M_I$ as a function of these parameters.~Our emulator enables the use of Markov Chain Monte Carlo simulations where the axion-electron coupling $\alpha_{26}$ is varied simultaneously with the stellar parameters. We find that, once stellar uncertainties and degeneracies are accounted for, the region $\alpha_{26} < 2$ is not excluded by empirical TRGB calibrations.~Our work opens up a large region of parameter space currently believed to be excluded.~$\alpha_{26} = 2$ is the upper limit of the parameter space considered by this study, and it is likely that larger values of $\alpha_{26}$ are also unconstrained.~We discuss potential applications of our work to reevaluate other astrophysical probes of new physics.

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M. Dennis and J. Sakstein
Mon, 8 May 23
26/63

Comments: 14 pages, 6 figures, 1 table, dataset at this https URL

Black Holes as the source of the dark energy: a stringent test with the high-redshift JWST AGNs [CEA]

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http://arxiv.org/abs/2305.03408


It has been suggested that there is evidence for cosmological coupling of black holes (BHs) with an index of $k\approx 3$ and hence the BHs serve as the astrophysical source of the dark energy. The data sample however is limited for the redshifts $\leq 2.5$. Recently, the James Webb Space Telescope (JWST) has detected more than 180 high-redshift Active Galactic Nuclei (AGNs) and quasars. Among the JWST NIRSpec/NIRCam resolved AGNs, three are identified in early-type host galaxies with a redshift $z\sim 4.5-7$. Their $M_{\star}$ and $M_{\rm BH}$, however, are in tension with the prediction of the cosmological coupling of black holes with $k=3$ at a confidence level of $\sim 3\sigma$, which is not in support of the hypothesis that BHs serve as the origin of dark energy. The future observations of high-redshift AGNs by JWST will further test such a hypothesis by identifying more early-type host galaxies in the higher mass range.

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L. Lei, L. Zu, G. Yuan, et. al.
Mon, 8 May 23
40/63

Comments: 9 pages, 3 figures, 1 table; Submitted to ApJL. Comments are welcome!

Gravitational freeze-in dark matter from Higgs Preheating [CL]

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http://arxiv.org/abs/2305.02568


Gravitational freeze-in is a mechanism to explain the observed dark matter relic density if dark matter neither couples to inflation nor to standard model sector. In this work, we study gravitational freeze-in dark matter production during Higgs preheating based on non-perturbative resonance. Using reliable lattice method to handle this non-perturbative process, we show that tachyonic resonance is prohibited by strong back reaction due to Higgs self interaction needed to keep the positivity of potential during preheating, and parameter resonance is viable by tuning the Higgs self-interaction coupling to be small enough in ultraviolet energy scale. We then derive the dark matter relic density under the context of Higgs preheating, and uncover a new dark matter parameter space with dark matter mass larger than inflaton mass, which arises from out-of-equilium Higgs annihilation. Finally, we briefly remark the open question of testing gravitational dark matter.

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R. Zhang, Z. Xu and S. Zheng
Mon, 8 May 23
47/63

Comments: 18 pages, 5 figures

Present and future constraints on flavor-dependent long-range interactions of high-energy astrophysical neutrinos [CL]

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http://arxiv.org/abs/2305.03675


The discovery of new, flavor-dependent neutrino interactions would provide compelling evidence of physics beyond the Standard Model. We focus on interactions generated by the anomaly-free, gauged, abelian lepton-number symmetries, specifically $L_e-L_\mu$, $L_e-L_\tau$, and $L_\mu-L_\tau$, that introduce a new matter potential sourced by electrons and neutrons, potentially impacting neutrino flavor oscillations. We revisit, revamp, and improve the constraints on these interactions that can be placed via the flavor composition of the diffuse flux of high-energy astrophysical neutrinos, with TeV-PeV energies, i.e., the proportion of $\nu_e$, $\nu_\mu$, and $\nu_\tau$ in the flux. Because we consider mediators of these new interactions to be ultra-light, lighter than $10^{-10}$ eV, the interaction range is ultra-long, from km to Gpc, allowing vast numbers of electrons and neutrons in celestial bodies and the cosmological matter distribution to contribute to this new potential. We leverage the present-day and future sensitivity of high-energy neutrino telescopes and of oscillation experiments to estimate the constraints that could be placed on the coupling strength of these interactions. We find that, already today, the IceCube neutrino telescope demonstrates potential to constrain flavor-dependent long-range interactions significantly better than existing constraints, motivating further analysis. We also estimate the improvement in the sensitivity due to the next-generation neutrino telescopes such as IceCube-Gen2, Baikal-GVD, KM3NeT, P-ONE, and TAMBO.

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S. Agarwalla, M. Bustamante, S. Das, et. al.
Mon, 8 May 23
49/63

Comments: 46 pages, 17 figures, 2 tables, 6 appendices. Comments are welcome

Detecting ALP wiggles at TeV energies [CL]

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http://arxiv.org/abs/2305.03604


Axions and axion-like-particles (ALPs) are characterised by their two-photon coupling, which entails so-called photon-ALP oscillations as photons propagate through a magnetic field. These oscillations lead to distinctive signatures in the energy spectrum of high-energy photons from astrophysical sources, allowing one to probe the existence of ALPs. In particular, photon-ALP oscillations will induce energy dependent oscillatory features, or “ALP wiggles”, in the photon spectra. We propose to use the discrete power spectrum to search for ALP wiggles and present a model-independent statistical test. By using PKS 2155-304 as an example, we show that the method has the potential to significantly improve the experimental sensitivities for ALP wiggles. Moreover, we discuss how these sensitivities depend on the modelling of the magnetic field. We find that the use of realistic magnetic field models, due to their larger cosmic variance, substantially enhances detection prospects compared to the use of simplified models.

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M. Kachelriess and J. Tjemsland
Mon, 8 May 23
52/63

Comments: 21 pages, 9 figures

Dissipative Genesis of the Inflationary Universe [CL]

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http://arxiv.org/abs/2305.02366


We study an inflation model with a flat scalar potential supported by observations and find that slow-roll inflation can emerge after a quasi-cyclic phase of the Universe, where it undergoes repeated expansions and contractions for a finite time period. The initial conditions and the positive spatial curvature required for such nontrivial dynamics align with the quantum creation of the Universe. The key ingredients that trigger inflation are dissipative interactions of the inflaton, which are necessary to reheat the Universe after inflation and thus give us an observational handle on pre-inflationary physics. Our discovery implies that inflation occurs more robustly after the creation.

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H. Matsui, A. Papageorgiou, F. Takahashi, et. al.
Fri, 5 May 23
8/67

Comments: 5 pages, 1 figure

Cosmological phase transitions: from perturbative particle physics to gravitational waves [CL]

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http://arxiv.org/abs/2305.02357


Gravitational waves (GWs) were recently detected for the first time. This revolutionary discovery opens a new way of learning about particle physics through GWs from first-order phase transitions (FOPTs) in the early Universe. FOPTs could occur when new fundamental symmetries are spontaneously broken down to the Standard Model and are a vital ingredient in solutions of the matter anti-matter asymmetry problem. The path from a particle physics model to GWs, however, contains many specialized parts and so here we provide a timely review of all the required steps, including: (i) building a finite-temperature effective potential in a particle physics model and checking for FOPTs; (ii) computing transition rates; (iii) analyzing the dynamics of bubbles of true vacuum expanding in a thermal plasma; (iv) characterizing a transition using thermal parameters; and, finally, (v) making predictions for GW spectra using the latest simulations and theoretical results and considering the detectability of predicted spectra at future GW detectors. For each step we emphasize the subtleties, advantages and drawbacks of different methods, discuss open questions and review the state-of-art approaches available in the literature. This provides everything a particle physicist needs to begin exploring GW phenomenology.

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P. Athron, C. Balázs, A. Fowlie, et. al.
Fri, 5 May 23
43/67

Comments: 155 pages, 20 figures, review submitted to Progress in Particle and Nuclear Physics

The FLUKA cross sections for cosmic-ray leptons and uncertainties on current positron predictions [HEAP]

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http://arxiv.org/abs/2305.02958


Cosmic-ray (CR) antiparticles have the potential to reveal signatures of unexpected astrophysical processes and even new physics beyond the Standard Model. Recent CR detectors have provided accurate measurements of the positron flux, revealing the so-called positron excess at high energies. However, the uncertainties related to the modelling of the local positron flux are still very high, significantly affecting our models of positron emission from pulsars and current dark matter searches.
In this work, we report a new set of cross sections for positron and electron production derived from the {\tt FLUKA} code. We compare them with the most extended cross-section data-sets and show the impact of neglecting the positron production from heavy CRs. Then, we review the most significant sources of uncertainties in our current estimations of the secondary positron flux at Earth and examine for the first time the impact of considering the spiral arm structure of the Galaxy in these estimations. Finally, we provide state-of-the-art predictions of the local positron flux and discuss the limitations of our dark matter searches with positrons and difficulties to determine the contribution from pulsars to the positron flux at low energies.

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P. Luque, M. Mazziotta and F. Loparco
Fri, 5 May 23
48/67

Comments: 30 pages, 15 figures and no tables

Dissipative Emergence of Inflation from Quasi-Cyclic Universe [CL]

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http://arxiv.org/abs/2305.02367


Inflationary models, especially those with plateau-type potentials, are consistent with the cosmological data, but inflation itself does not resolve the initial singularity. This singularity is resolved, for example, by the idea of the quantum creation of the Universe from nothing such as the tunneling and no-boundary proposals. The simplest one predicts a closed Universe. Motivated by these facts, we investigate the classical dynamics of a closed Universe with a plateau-type potential. Depending on the initial inflaton field value, the Universe can undergo a variety of events: an immediate Big Crunch, a bounce or cyclic phase, and inflation. Although the non-inflationary solutions may appear irrelevant to our Universe, they can be turned into a single or multiple bounces followed by inflation, taking into account the interactions necessary for the reheating of the Universe after inflation. Thus, the dissipative mechanism in our setup explains both the graceful entry to and exit from inflation and gives us an indirect observational handle on the Universe just after creation. We also comment on the implications of these solutions on the probabilistic interpretations of the wave function of the Universe.

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H. Matsui, A. Papageorgiou, F. Takahashi, et. al.
Fri, 5 May 23
49/67

Comments: 53 pages, 11 figures

de Sitter Space Decay and Cosmological Constant Relaxation in Braney Unimodular Gravity [CL]

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http://arxiv.org/abs/2305.02349


General covariant unimodular gravity frameworks, based on the Henneaux-Teitelboim formulation, are, in disguise, precisely $4$-form field theories corrected with higher dimension operators. In the presence of charged tensional membranes, any de Sitter space in all such theories is unstable and decays. If the fluxes sourced by membranes are mutually incommensurate, de Sitter geometries comprise a very refined discretuum of states. Whenever the $4$-form sector is dominated by terms linear in flux the almost-Minkowski space is the unique long-time attractor. As a result, a tiny cosmological constant is natural in all such frameworks, without appealing to anthropic reasoning.

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N. Kaloper
Fri, 5 May 23
67/67

Comments: 28 pages, 5 figures

Constraints on dark matter-neutrino scattering from the Milky-Way satellites and subhalo modeling for dark acoustic oscillations [CEA]

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http://arxiv.org/abs/2305.01913


The elastic scattering between dark matter (DM) and radiation can potentially explain small-scale observations that the cold dark matter faces as a challenge, as damping density fluctuations via dark acoustic oscillations in the early universe erases small-scale structure. We study a semi-analytical subhalo model for interacting dark matter with radiation, based on the extended Press-Schechter formalism and subhalos’ tidal evolution prescription. We also test the elastic scattering between DM and neutrinos using observations of Milky-Way satellites from the Dark Energy Survey and PanSTARRS1. We conservatively impose strong constraints on the DM-neutrino scattering cross section of $\sigma_{{\rm DM}\text{-}\nu,n}\propto E_\nu^n$ $(n=0,2,4)$ at $95\%$ confidence level (CL), $\sigma_{{\rm DM}\text{-}\nu,0}< 10^{-32}\ {\rm cm^2}\ (m_{\rm DM}/{\rm GeV})$, $\sigma_{{\rm DM}\text{-}\nu,2}< 10^{-43}\ {\rm cm^2}\ (m_{\rm DM}/{\rm GeV})(E_\nu/E_{\nu}^0)^2$ and $\sigma_{{\rm DM}\text{-}\nu,4}< 10^{-54}\ {\rm cm^2}\ (m_{\rm DM}/{\rm GeV})(E_\nu/E_{\nu}^0)^4$, where $E_\nu^0$ is the average momentum of relic cosmic neutrinos today, $E_\nu^0 \simeq 3.15 T_\nu^0 \simeq 6.1\ {\rm K}$. By imposing a satellite forming condition, we obtain the strongest upper bounds on the DM-neutrino cross section at $95\%$ CL, $\sigma_{{\rm DM}\text{-}\nu,0}< 4\times 10^{-34}\ {\rm cm^2}\ (m_{\rm DM}/{\rm GeV})$, $\sigma_{{\rm DM}\text{-}\nu,2}< 10^{-46}\ {\rm cm^2}\ (m_{\rm DM}/{\rm GeV})(E_\nu/E_{\nu}^0)^2$ and $\sigma_{{\rm DM}\text{-}\nu,4}< 7\times 10^{-59}\ {\rm cm^2}\ (m_{\rm DM}/{\rm GeV})(E_\nu/E_{\nu}^0)^4$.

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K. Akita and S. Ando
Thu, 4 May 23
19/60

Comments: 18 pages, 6 figures

The self-confinement of electrons and positrons from dark matter [HEAP]

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http://arxiv.org/abs/2305.01999


Radiative emissions from electrons and positrons generated by dark matter (DM) annihilation or decay are one of the most investigated signals in indirect searches of WIMPs. Ideal targets must have large ratio of DM to baryonic matter. However, such “dark” systems have a poorly known level of magnetic turbulence, which determines the residence time of the electrons and positrons and therefore also the strength of the expected signal. This typically leads to significant uncertainties in the derived DM bounds. In a novel approach, we compute the self-confinement of the DM-induced electrons and positrons. Indeed, they themselves generate irregularities in the magnetic field, thus setting a lower limit on the presence of the magnetic turbulence. We specifically apply this approach to dwarf spheroidal galaxies. Finally, by comparing the expected synchrotron emission with radio data from the direction of the Draco galaxy collected at the Giant Metre Radio Telescope, we show that the proposed approach can be used to set robust and competitive bounds on WIMP DM.

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M. Regis, M. Korsmeier, G. Bernardi, et. al.
Thu, 4 May 23
20/60

Comments: 18 pages, 9 figures

Methods and prospects for gravitational wave searches targeting ultralight vector boson clouds around known black holes [CL]

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http://arxiv.org/abs/2305.00401


Ultralight bosons are predicted in many extensions to the Standard Model and are popular dark matter candidates. The black hole superradiance mechanism allows for these particles to be probed using only their gravitational interaction. In this scenario, an ultralight boson cloud may form spontaneously around a spinning black hole and extract a non-negligible fraction of the black hole’s mass. These oscillating clouds produce quasi-monochromatic, long-duration gravitational waves that may be detectable by ground-based or space-based gravitational wave detectors. We discuss the capability of a new long-duration signal tracking method, based on a hidden Markov model, to detect gravitational wave signals generated by ultralight vector boson clouds, including cases where the signal frequency evolution timescale is much shorter than that of a typical continuous wave signal. We quantify the detection horizon distances for vector boson clouds with current- and next-generation ground-based detectors. We demonstrate that vector clouds hosted by black holes with mass $\gtrsim 60 M_{\odot}$ and spin $\gtrsim 0.6$ are within the reach of current-generation detectors up to a luminosity distance of $\sim 1$ Gpc. This search method enables one to target vector boson clouds around remnant black holes from compact binary mergers detected by gravitational-wave detectors. We discuss the impact of the sky localization of the merger events and demonstrate that a typical remnant black hole reasonably well-localized by the current generation detector network is accessible in a follow-up search.

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D. Jones, L. Sun, N. Siemonsen, et. al.
Thu, 4 May 23
27/60

Comments: 20 pages, 12 figures

The dark matter unitarity bound at NLO [CL]

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http://arxiv.org/abs/2305.01680


We reexamine the consequences of perturbative unitarity on dark matter freeze-out when both Sommerfeld enhancement and bound state formation affect dark matter annihilations. At leading order (LO) the annihilation cross-section is infrared dominated and the connection between the unitarity bound and the upper bound on the dark matter mass depends only on how the different partial waves are populated. We compute how this picture is modified at next-to-leading order (NLO) with the goal of assigning a reliable theory uncertainty to the freeze-out predictions. We explicitly compute NLO corrections in a simple model with abelian gauge interactions and provide an estimate of the theoretical uncertainty for the thermal masses of heavy electroweak $n$-plets. Along the way, we clarify the regularization and matching procedure necessary to deal with singular potentials in quantum mechanics with a calculable relativistic UV completion.

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S. Bottaro and D. Redigolo
Thu, 4 May 23
35/60

Comments: 8 pages + appendices, 5+2 figures

Constraining the dark matter interpretation of the positron excess with $γ$-ray data [HEAP]

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http://arxiv.org/abs/2305.01992


The particle origin of dark matter (DM) is still one of the main puzzles in modern physics. One of the most promising search strategy to detect DM at laboratories is through the indirect search of cosmic particles that are produced from DM annihilation in space. In particular, the flux of cosmic positrons has been measured with high precision by the AMS-02 experiment demonstrating that an excess above 10 GeV, with respect to the secondary production, is present. We study in this paper the possible DM origin of the positron excess finding the values of the DM mass $M$ and annihilation cross section $\langle \sigma v \rangle$ that are needed to fit high-energy positron data. In particular, we find that for DM annihilating into $b\bar{b}$ it is required to have $M=43$ TeV and $\langle \sigma v \rangle = 10^{-21}$ cm$^3$/s while for $\tau^+\tau^-$ $M=2$ TeV and $\langle \sigma v \rangle = 3\times 10^{-23}$ cm$^3$/s. If DM produce positrons, they are expected to generate gamma rays from the center of the Milky Way and around dwarf galaxy satellites of the Galaxy. We thus combine the values for the DM mass and annihilation cross section obtained with the fit to AMS-02 positron data with the upper limits derived with the non-detection of $\gamma$ rays with HESS in the direction of the Galactic center and Fermi-LAT for the combined analysis of dwarf galaxies. The main result of the paper is that only DM annihilating into $\mu^+ \mu^-$ with a mass around 500 GeV and $\langle \sigma v \rangle = 4\times 10^{-24}$ cm$^3$/s can fit AMS-02 data and be compatible with the upper limits found with $\gamma$ rays. As for the $\tau^+ \tau^-$ ($b\bar{b}$) channel, DM can contribute at most at a few tens $\%$ (a few \%) level.

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H. Zhan
Thu, 4 May 23
37/60

Comments: 15 pages, 6 figures, 2 tables. Comments are welcome

Precision CMB constraints on eV-scale bosons coupled to neutrinos [CL]

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http://arxiv.org/abs/2305.01692


The cosmic microwave background (CMB) has proven to be an invaluable tool for studying the properties and interactions of neutrinos, providing insight not only into the sum of neutrino masses but also the free streaming nature of neutrinos prior to recombination. The CMB is a particularly powerful probe of new eV-scale bosons interacting with neutrinos, as these particles can thermalize with neutrinos via the inverse decay process, $\nu\bar{\nu} \rightarrow X$, and suppress neutrino free streaming near recombination — even for couplings as small as $\lambda_\nu \sim \mathcal{O}(10^{-13})$. Here, we revisit CMB constraints on such bosons, improving upon a number of approximations previously adopted in the literature and generalizing the constraints to a broader class of models. This includes scenarios in which the boson is either spin-$0$ or spin-$1$, the number of interacting neutrinos is either $N_{\rm int} = 1,2 $ or $3$, and the case in which a primordial abundance of the species is present. We apply these bounds to well-motivated models, such as the singlet majoron model or a light $U(1){L\mu-L_\tau}$ gauge boson, and find that they represent the leading constraints for masses $m_X\sim 1\, {\rm eV}$. Finally, we revisit the extent to which neutrino-philic bosons can ameliorate the Hubble tension, and find that recent improvements in the understanding of how such bosons damp neutrino free streaming reduces the previously found success of this proposal.

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S. Sandner, M. Escudero and S. Witte
Thu, 4 May 23
49/60

Comments: 9 + 8 pages, 14 figures

What can a GNOME do? Search targets for the Global Network of Optical Magnetometers for Exotic physics searches [CL]

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http://arxiv.org/abs/2305.01785


Numerous observations suggest that there exist undiscovered beyond-the-Standard-Model particles and fields. Because of their unknown nature, these exotic particles and fields could interact with Standard Model particles in many different ways and assume a variety of possible configurations. Here we present an overview of the Global Network of Optical Magnetometers for Exotic physics searches (GNOME), our ongoing experimental program designed to test a wide range of exotic physics scenarios. The GNOME experiment utilizes a worldwide network of shielded atomic magnetometers (and, more recently, comagnetometers) to search for spatially and temporally correlated signals due to torques on atomic spins from exotic fields of astrophysical origin. We survey the temporal characteristics of a variety of possible signals currently under investigation such as those from topological defect dark matter (axion-like particle domain walls), axion-like particle stars, solitons of complex-valued scalar fields (Q-balls), stochastic fluctuations of bosonic dark matter fields, a solar axion-like particle halo, and bursts of ultralight bosonic fields produced by cataclysmic astrophysical events such as binary black hole mergers.

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S. Afach, D. Tumturk, H. Bekker, et. al.
Thu, 4 May 23
55/60

Comments: 22 pages, 12 figures, submitted to Annalen der Physik

Detecting High-Frequency Gravitational Waves in Planetary Magnetosphere [CL]

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http://arxiv.org/abs/2305.01832


High-frequency gravitational waves (HFGWs) carry a wealth of information on the early Universe with a tiny comoving Hubble horizon and astronomical objects of small scale but with dense energy. We demonstrate that the nearby planets, such as Earth and Jupiter, can be utilized as a laboratory for detecting the HFGWs. These GWs are then expected to convert to signal photons in the planetary magnetosphere, across the frequency band of astronomical observation. As a proof of concept, we present the first limits from the existing low-Earth-orbit satellite for specific frequency bands and project the sensitivities for the future more-dedicated detections. The first limits from Juno, the latest mission orbiting Jupiter, are also presented. Attributed to the long path of effective GW-photon conversion and the wide angular distribution of signal flux, we find that these limits are highly encouraging, for a broad range of frequencies including a large portion unexplored before.

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T. Liu, J. Ren and C. Zhang
Thu, 4 May 23
57/60

Comments: 11 pages, 8 figures

Impacts of dark matter interaction on nuclear and neutron star matter within the relativistic mean-field model [CL]

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http://arxiv.org/abs/2305.02065


This thesis explores the effects of dark matter (DM) on neutron stars (NSs) using the relativistic mean-field (RMF) model. The effects of DM on NS properties, including the mass-radius relation, the moment of inertia, and tidal deformability, are calculated by varying its fraction. The study found that the EOS becomes softer with increasing DM momentum, and the DM has marginal effects on nuclear matter properties, except for the EOSs and binding energy per particle. The study also calculated the properties of isolated, static, and rotating DM admixed NS and found that the DM has significant effects on both static and rotating NS. We have also observed that a tiny amount of DM can accumulate inside the NS, and more amount of it makes the NS unstable. The study also suggests that the secondary component might be a NS with DM content if the underlying nuclear EOS is sufficiently stiff. The $f$-mode oscillations of the DM admixed hyperon stars are calculated and found that there exist a correlation between canonical $f$-mode frequency and the dimensionless tidal deformability parameter ($\Lambda_{1.4}$) and we have put a constraint on $f$-mode frequency using GW170817 data. Finally, we have calculated the DM admixed binary NS properties and found that the binary system becomes less deformed and sustains more time in its inspiral phases with the addition of DM. Therefore, we suggest that one can take DM inside the compact objects while modeling the inspiral waveforms for the BNS systems.

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H. Das
Thu, 4 May 23
58/60

Comments: PhD Thesis

Quantum information and quantum simulation of neutrino physics [CL]

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http://arxiv.org/abs/2305.01150


In extreme astrophysical environments such as core-collapse supernovae and binary neutron star mergers, neutrinos play a major role in driving various dynamical and microphysical phenomena, such as baryonic matter outflows, the synthesis of heavy elements, and the supernova explosion mechanism itself. The interactions of neutrinos with matter in these environments are flavor-specific, which makes it of paramount importance to understand the flavor evolution of neutrinos. Flavor evolution in these environments can be a highly nontrivial problem thanks to a multitude of collective effects in flavor space, arising due to neutrino-neutrino ($\nu$-$\nu$) interactions in regions with high neutrino densities. A neutrino ensemble undergoing flavor oscillations under the influence of significant $\nu$-$\nu$ interactions is somewhat analogous to a system of coupled spins with long-range interactions among themselves and with an external field (‘long-range’ in momentum-space in the case of neutrinos). As a result, it becomes pertinent to consider whether these interactions can give rise to significant quantum correlations among the interacting neutrinos, and whether these correlations have any consequences for the flavor evolution of the ensemble. In particular, one may seek to utilize concepts and tools from quantum information science and quantum computing to deepen our understanding of these phenomena. In this article, we attempt to summarize recent work in this field. Furthermore, we also present some new results in a three-flavor setting, considering complex initial states.

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A. Balantekin, M. Cervia, A. Patwardhan, et. al.
Wed, 3 May 23
11/67

Comments: 13 pages, 3 figures. Invited review for the Eur. Phys. J. A special issue on “Quantum computing in low-energy nuclear theory”

Extended Analysis of Neutrino-Dark Matter Interactions with Small-Scale CMB Experiments [CEA]

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http://arxiv.org/abs/2305.01383


We explore an extension of the standard $\Lambda$CDM model by including an interaction between neutrinos and dark matter, and making use of the ground based telescope data of the Cosmic Microwave Background (CMB) from the Atacama Cosmology Telescope (ACT). An indication for a non-zero coupling between dark matter and neutrinos (both assuming a temperature independent and $T^2$ dependent cross-section) is obtained at the 1$\sigma$ level coming from the ACT CMB data alone and when combined with the Planck CMB and Baryon Acoustic Oscillations (BAO) measurements. This result is confirmed by both fixing the effective number of relativistic degrees of freedom in the early Universe to the Standard Model value of $N_{\rm eff}=3.044$, and allowing $N_{\rm eff}$ to be a free cosmological parameter. Furthermore, when performing a Bayesian model comparison, the interacting $\nu$DM (+$N_{\rm eff}$) scenario is mostly preferred over a baseline $\Lambda$CDM (+$N_{\rm eff}$) cosmology. The preferred value is then used as a benchmark and the potential implications of dark matter’s interaction with a sterile neutrino are discussed.

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P. Brax, C. Bruck, E. Valentino, et. al.
Wed, 3 May 23
28/67

Comments: 18 pages, 11 figures, 5 tables

The average equation of state for the oscillating inflaton field of the simplest $α$-attractor E-model [CL]

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http://arxiv.org/abs/2305.01159


In this work, we calculate the average equation of state for the oscillating inflaton field of the simplest $\alpha$-attractor E-model. We show that the average equation of state can be solved analytically. We discover that when $\alpha$ is small, the average equation of state of the oscillating inflaton field approaches that of a cosmological constant. This is the phenomenon of oscillating inflation.

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C. Lin
Wed, 3 May 23
44/67

Comments: 9 pages, 3 figures

Self-similar growth of Bose stars [CEA]

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http://arxiv.org/abs/2305.01005


We analytically solve the problem of Bose star growth in the bath of gravitationally interacting particles. We find that after nucleation of this object, the bath is described by a self-similar solution of the kinetic equation, which is an attractor. Together with the conservation laws, this fixes mass evolution of the Bose star. Our results explain slowdown of the star growth at a certain “core-halo” mass, but also predict formation of the heavier and lighter objects in magistral dark matter models.

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A. Dmitriev, D. Levkov, A. Panin, et. al.
Wed, 3 May 23
46/67

Comments: 4 pages, 2 figures

First Constraints on the Photon Coupling of Axion-like Particles from Multimessenger Studies of the Neutron Star Merger GW170817 [CL]

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http://arxiv.org/abs/2305.01002


We use multimessenger observations of the neutron star merger event GW170817 to derive new constraints on axion-like particles (ALPs) coupling to photons. ALPs are produced via Primakoff and photon coalescence processes in the merger, escape the remnant and decay back into two photons, giving rise to a photon signal approximately along the line-of-sight to the merger. We analyze the spectral and temporal information of the ALP-induced photon signal, and use the Fermi-LAT observations of GW170817 to derive our new ALP constraints. We also show the improved prospects with future MeV gamma-ray missions, taking the spectral and temporal coverage of AMEGO-X as an example.

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P. Dev, J. Fortin, S. Harris, et. al.
Wed, 3 May 23
47/67

Comments: 8+8 pages, 4+6 figures

Fundamental cosmology from ANDES precision spectroscopy [IMA]

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http://arxiv.org/abs/2305.01446


Fundamental cosmology observations, such as the detection of the redshift drift and tests of the universality of physical laws, are key science and design drivers of the ArmazoNes high Dispersion Echelle Spectrograph (ANDES), an Extremely Large Telescope instrument. While separate forecasts for each of them have been reported, we have developed Fisher Matrix based forecast tools combining both of these observables. We demonstrate the synergies between the two ANDES datasets, quantifying the improvements in cosmology and fundamental physics parameter constraints for two separate theoretical paradigms. We publicly release this forecast code, which is one of the tools for the optimisation of the ANDES observing strategy.

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C. Marques, C. Martins and C. Alves
Wed, 3 May 23
60/67

Comments: 8 pages, 3 figures, 2 tables, MNRAS (in press)

Generalizations of Quasilinear MOND (QUMOND) [GA]

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http://arxiv.org/abs/2305.01589


I present a class of theories that generalize quasilinear MOND (QUMOND). Like QUMOND, these GQUMOND theories require solving only the linear Poisson equation (twice). Unlike QUMOND, their Lagrangian depends on higher derivatives of the Newtonian potential. They thus dictate different “phantom” densities as virtual sources in the Poisson equation for the MOND potential. These theories might open new avenues to more fundamental theories, and have much heuristic value. I use them to demonstrate that even within limited classes of modified-gravity formulations of MOND, theories can differ substantially on lower-tier MOND predictions. Such GQUMOND theories force, generically, the introduction of dimensioned constants other than the MOND acceleration, $a_0$, such as a length, a frequency, etc. As a result, some of these theories reduce to QUMOND itself only, e.g., on length scales (or, in other versions, dynamical times) larger than some critical value. But in smaller systems (or, alternatively, in ones with shorter dynamical times), MOND effects are screened, even if their internal accelerations are smaller than $a_0$. In such theories it is possible that MOND (expressed as QUMOND) applies on galactic scales, but its departures from Newtonian dynamics are substantially suppressed in some subgalactic systems — such as binary stars, and open, or globular star clusters. The same holds for the effect of the galactic field on dynamics in the inner solar system, which can be greatly suppressed compared with what QUMOND predicts. Tidal effects of a galaxy on smaller subsystems are the same as in QUMOND, for the examples I consider. I also describe briefly versions that do not involve dimensioned constants other than $a_0$, and yet differ from QUMOND in important ways.

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M. Milgrom
Wed, 3 May 23
61/67

Comments: 12 pages

Hydrodynamic sound shell model [CL]

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http://arxiv.org/abs/2305.00074


For a cosmological first-order phase transition in the early Universe, the associated stochastic gravitational wave background is usually dominated by sound waves from plasma fluid motions, which have been analytically modeled as a random superposition of freely propagating sound shells but with the force by the scalar field that produces the self-similar profile removed. In this Letter, we propose a new analytic sound shell model by focusing on the forced propagating contribution from the initial collision stage of sound shells when their self-similar profiles are still maintained by the moving bubble walls. We reproduce the causal $k^3$-scaling in the infrared consistent with numerical simulations, and also recover the broad dome in the power spectrum first observed in numerical simulations. The total sound waves should contain both contributions from forced collisions and free propagation of sound shells at early and late stages of the phase transition, respectively.

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R. Cai, S. Wang and Z. Yuwen
Tue, 2 May 23
7/57

Comments: 5 pages (3 figures) + 1 appendix (5 figures)

Bayesian Inference of Supernova Neutrino Spectra with Multiple Detectors [CL]

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http://arxiv.org/abs/2305.00392


We implement the Bayesian inference to retrieve energy spectra of all neutrinos from a galactic core-collapse supernova (CCSN). To achieve high statistics and full sensitivity to all flavours of neutrinos, we adopt a combination of several reaction channels from different large-scale neutrino observatories, namely inverse beta decay on proton and elastic scattering on electron from Hyper-Kamiokande (Hyper-K), charged current absorption on Argon from Deep Underground Neutrino Experiment (DUNE) and coherent elastic scattering on Lead from RES-NOVA. Assuming no neutrino oscillation or specific oscillation models, we obtain mock data for each channel through Poisson processes with the predictions, for a typical source distance of 10 kpc in our Galaxy, and then evaluate the probability distributions for all spectral parameters of theoretical neutrino spectrum model with Bayes’ theorem. Although the results for either the electron-neutrinos or electron-antineutrinos reserve relatively large uncertainties (according to the neutrino mass hierarchy), a precision of a few percent (i.e., $\pm 1 \% \sim \pm 4 \%$ at a credible interval of $2 \sigma$) is achieved for primary spectral parameters (e.g., mean energy and total emitted energy) of other neutrino species. Moreover, the correlation coefficients between different parameters are computed as well and interesting patterns are found. Especially, the mixing-induced correlations are sensitive to the neutrino mass hierarchy, which potentially makes it a brand new probe to determine the neutrino mass hierarchy in the detection of galactic supernova neutrinos. Finally, we discuss the origin of such correlation patterns and perspectives for further improvement on our results.

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X. Huang, C. Sun, L. Chen, et. al.
Tue, 2 May 23
27/57

Comments: 24 pages, 7 figures, 4 tables

Observational constraints on power law Starobinsky inflation [CEA]

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http://arxiv.org/abs/2305.00682


In this work we revisit power law, $\frac{1}{M^2}R^\beta$, inflation to find the deviations from $R^2$ inflation allowed by current CMB and LSS observations. We compute the power spectra for scalar and tensor perturbations numerically and perform MCMC analysis to put constraints on parameters $M$ and $\beta$ from Planck-2018, BICEP3 and other LSS observations. We consider general reheating scenario and also vary the number of e-foldings during inflation, $N_{pivot}$, along with the other parameters. We find $\beta = 1.966^{+0.035}{-0.042}$, $M= \left(3.31^{+5}{-2}\right)\times 10^{-5}$ and $N_{pivot} = 41^{+10}_{-10}$ with $95\%\, C.\, L.$. This indicates that the current observations allow deviation from Starobinsky inflation. The scalar spectral index, $n_s$, and tensor-to-scalar ratio, $r$, derived from these parameters, are consistent with the Planck and BICEP3 observations.

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S. Saini and A. Nautiyal
Tue, 2 May 23
34/57

Comments: 13 pages, 5 figures

Starobinsky-Type B-L Higgs Inflation Leading Beyond MSSM [CL]

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http://arxiv.org/abs/2305.00523


Models of induced-gravity inflation are formulated within Supergravity employing as inflaton the Higgs field which leads to a spontaneous breaking of a U(1)_{B-L} symmetry at Mgut=2×10^16 GeV. We use a renormalizable superpotential, fixed by a U(1) R symmetry, and logarithmic or semi-logarithmic Kahler potentials with integer prefactors which exhibit a quadratic non-minimal coupling to gravity. We find inflationary solutions of Starobinsky type in accordance with the observations. The inflaton mass is predicted to be of the order of 10^13 GeV. The model can be nicely linked to MSSM offering an explanation of the magnitude of the mu parameter consistently with phenomenological data. Also it allows for baryogenesis via non-thermal leptogenesis, provided that the gravitino is heavier than about 10 TeV.

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C. Pallis
Tue, 2 May 23
42/57

Comments: Prepared for the Proceedings of the Corfu Summer Institute 2022 — Conference: C22-08-28. arXiv admin note: substantial text overlap with arXiv:1804.07038