Prospects for Detecting the Diffuse Supernova Neutrino Background with JUNO [CL]

http://arxiv.org/abs/2205.08830


We present the detection potential for the diffuse supernova neutrino background (DSNB) at the Jiangmen Underground Neutrino Observatory (JUNO), using the inverse-beta-decay (IBD) detection channel on free protons. We employ the latest information on the DSNB flux predictions, and investigate in detail the background and its reduction for the DSNB search at JUNO. The atmospheric neutrino induced neutral current (NC) background turns out to be the most critical background, whose uncertainty is carefully evaluated from both the spread of model predictions and an envisaged \textit{in situ} measurement. We also make a careful study on the background suppression with the pulse shape discrimination (PSD) and triple coincidence (TC) cuts. With latest DSNB signal predictions, more realistic background evaluation and PSD efficiency optimization, and additional TC cut, JUNO can reach the significance of 3$\sigma$ for 3 years of data taking, and achieve better than 5$\sigma$ after 10 years for a reference DSNB model. In the pessimistic scenario of non-observation, JUNO would strongly improve the limits and exclude a significant region of the model parameter space.

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J. Collaboration, A. Abusleme, T. Adam, et. al.
Thu, 19 May 22
10/61

Comments: N/A

Event reconstruction of Compton telescopes using a multi-task neural network [IMA]

http://arxiv.org/abs/2205.08082


We have developed a neural network model to perform event reconstruction of Compton telescopes. This model reconstructs events that consist of three or more interactions in a detector. It is essential for Compton telescopes to determine the time order of the gamma-ray interactions and whether the incident photon deposits all energy in a detector or it escapes from the detector. Our model simultaneously predicts these two essential factors using a multi-task neural network with three hidden layers of fully connected nodes. For verification, we have conducted numerical experiments using Monte Carlo simulation, assuming a large-area Compton telescope using liquid argon to measure gamma rays with energies up to $3.0\,\mathrm{MeV}$. The reconstruction model shows excellent performance of event reconstruction for multiple scattering events that consist of up to eight hits. The accuracies of hit order prediction are around $60\%$ while those of escape flags are higher than $70\%$ for up to eight-hit events of $4\pi$ isotropic photons. Compared with two other algorithms, a classical model and a physics-based probabilistic one, the present neural network method shows high performance in estimation accuracy particularly when the number of scattering is small, 3 or 4. Since simulation data easily optimize the network model, the model can be flexibly applied to a wide variety of Compton telescopes.

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S. Takashima, H. Odaka, H. Yoneda, et. al.
Wed, 18 May 22
39/66

Comments: 26 pages, 13 figures, 3 tables, accepted for publication in NIM A

Cosmology-friendly time-varying neutrino masses via the sterile neutrino portal [CL]

http://arxiv.org/abs/2205.08431


We investigate a consistent scenario of time-varying neutrino masses, and discuss its impact on cosmology, beta decay, and neutrino oscillation experiments. Such time-varying masses are assumed to be generated by the coupling between a sterile neutrino and an ultralight scalar field, which in turn affects the light neutrinos by mixing. We demonstrate how various cosmological bounds, such as those coming from Big Bang nucleosynthesis, the cosmic microwave background, as well as large scale structures, can be evaded in this model. This scenario can be further constrained using multiple terrestrial experiments. In particular, for beta-decay experiments like KATRIN, non-trivial distortions to the electron spectrum can be induced, even when time-variation is fast and gets averaged out. Furthermore, the presence of time-varying masses of sterile neutrinos will alter the interpretation of light sterile neutrino parameter space in the context of the reactor and gallium anomalies. In addition, we also study the impact of such time-varying neutrino masses on results from the BEST collaboration, which have recently strengthened the gallium anomaly. If confirmed, we find that the time-varying neutrino mass hypothesis could give a better fit to the recent BEST data.

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G. Huang, M. Lindner, P. Martínez-Miravé, et. al.
Wed, 18 May 22
60/66

Comments: 20 pages, 9 figures, comments welcome

VLBI observations of VIK J2318-3113, a quasar at z = 6.44 [CEA]

http://arxiv.org/abs/2205.05859


The nature of jets in active galactic nuclei (AGN) in the early Universe and their feedback to the host galaxy remain a highly topical question. Observations of the radio structure of high-redshift AGNs enabled by very long baseline interferometry (VLBI) provide indispensable input into studies of their properties and role in the galaxies’ evolution. Up to now, only five AGNs at redshift $z > 6$ have been studied with the VLBI technique. VIKJ2318-3113 is a recently discovered quasar at z = 6.44 that has not been imaged with VLBI before the current work. Here we present the first VLBI imaging results of this high-redshift quasar, with the aim of corroborating its high-resolution appearance with the physical model of the object. We carried out VLBI phase-referencing observations of VIKJ2318-3113 using the Very Long Baseline Array at two frequencies, 1.6 and 4.7 GHz, and obtained the first view at the radio structure on the milliarcsecond scale. The source was clearly detected at 1.6 GHz. We found that almost all of its radio emission comes from the pc-scale core region. Our dual-frequency observations constrain the spectral index and brightness temperature of the radio core. Its properties are similar to those of other known high-redshift radio-loud AGNs.

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Y. Zhang, T. An, A. Wang, et. al.
Fri, 13 May 22
44/64

Comments: 6 pages, 2 figures, accepted by A&A

A method for approximating optimal statistical significances with machine-learned likelihoods [CL]

http://arxiv.org/abs/2205.05952


Machine-learning techniques have become fundamental in high-energy physics and, for new physics searches, it is crucial to know their performance in terms of experimental sensitivity, understood as the statistical significance of the signal-plus-background hypothesis over the background-only one. We present here a new method that combines the power of current machine-learning techniques to face high-dimensional data with the likelihood-based inference tests used in traditional analyses, which allows us to estimate the sensitivity for both discovery and exclusion limits through a single parameter of interest, the signal strength. Based on supervised learning techniques, it can perform well also with high-dimensional data, when traditional techniques cannot. We apply the method to a toy model first, so we can explore its potential, and then to a LHC study of new physics particles in dijet final states. Considering as the optimal statistical significance the one we would obtain if the true generative functions were known, we show that our method provides a better approximation than the usual naive counting experimental results.

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E. Arganda, X. Marcano, V. Lozano, et. al.
Fri, 13 May 22
59/64

Comments: 22 pages, 8 figures. Comments welcome!

Ultra-High-Energy Cosmic Rays: The Intersection of the Cosmic and Energy Frontiers [HEAP]

http://arxiv.org/abs/2205.05845


The present white paper is submitted as part of the “Snowmass” process to help inform the long-term plans of the United States Department of Energy and the National Science Foundation for high-energy physics. It summarizes the science questions driving the Ultra-High-Energy Cosmic-Ray (UHECR) community and provides recommendations on the strategy to answer them in the next two decades.

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A. Coleman, J. Eser, E. Mayotte, et. al.
Fri, 13 May 22
60/64

Comments: Prepared as a solicited white paper for the 2021 Snowmass process. To be published in the Journal of High Energy Astrophysics

Power spectrum of domain-wall network and its implications for isotropic and anisotropic cosmic birefringence [CEA]

http://arxiv.org/abs/2205.05083


Recently, based on a novel analysis of the Planck satellite data, a hint of a uniform rotation of the polarization of cosmic microwave background photons, called isotropic cosmic birefringence, has been reported. The suggested rotation angle of polarization of about $0.2-0.4$ degrees strongly suggests that it is determined by the fine structure constant, which can be naturally explained over a very wide parameter range by the domain walls of axion-like particles. Interestingly, the axion-like particle domain walls predict not only isotropic cosmic birefringence but also anisotropic one that reflects the spatial distribution of the axion-like particle field on the last scattering surface. In this Letter, we perform lattice simulations of the formation and evolution of domain walls in the expanding universe and obtain for the first time the two-point correlation function and power spectrum of the scalar field that constitutes the domain walls. We find that while the power spectrum is generally consistent with analytical predictions based on random wall distributions, there is a predominant excess on the scale corresponding to the Hubble radius. Applying our results to the anisotropic cosmic birefringence, we predict the power spectrum of the rotation angles induced by the axion-like particle domain walls and show that it is within the reach of future observations of the cosmic microwave background.

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N. Kitajima, F. Kozai, F. Takahashi, et. al.
Thu, 12 May 22
3/63

Comments: 8pages, 7figures

First High-speed Camera Observations of the Optical Counterpart of a Terrestrial Gamma-ray Flash [CL]

http://arxiv.org/abs/2205.05115


In this paper, we present the first observation of optical emission of a downward-directed terrestrial gamma ray flash (TGF). The optical emission was observed by a high-speed video camera Phantom v2012 in conjunction with the Telescope Array (TA) surface detector, lightning mapping array, interferrometer, fast antenna, and the national lightning detection network. The suite of gamma and lightning instruments, timing resolution, and source proximity offers us an unprecedented look at the TGF phenomena. On September 11 of 2021 we observed a storm above the TA detector. The storm resulted in six extremely energetic TGF events that were produced by flashes with return stroke peak currents up to 223 kA. The observed TGFs were found to correlate directly to the initial burst pulse signal of the lightning flash while producing an intense optical signature. Results from this study allow us to furthers the understanding regarding the initiation mechanism of TGFs.

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R. Abbasi, J. J.W.Belz, M. Saba, et. al.
Thu, 12 May 22
12/63

Comments: N/A

Double cascade reconstruction in KM3NeT/ARCA [IMA]

http://arxiv.org/abs/2205.03613


The detection of astrophysical $\nu_\tau$ is an important verification of the observed flux of high-energy neutrinos. A flavour ratio of approximately $\nu_{e} : \nu_\mu : \nu_\tau \approx 1 : 1 : 1$ is predicted for astrophysical neutrinos measured at Earth due to neutrino oscillations. On top of this, the $\nu_\tau$ offers a unique channel for neutrino astronomy due to absence of an atmospheric $\nu_\tau$ background contribution. When a $\nu_\tau$ interacts it produces a particle cascade and often a $\tau$ lepton which in turn decays mainly into another cascade. This results in a double cascade signature. An excellent angular resolution can be achieved when both cascade vertices are reconstructed. The KM3NeT/ARCA detector, which is under construction in the Mediterranean sea, will be able to detect this signature due to its timing and spatial resolution for cascades. We will discuss the dedicated reconstruction algorithm and performance for reconstructing double cascades using KM3NeT. The angular deviation reaches sub-degree level for tau lengths larger than 25 meters.

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T. Eeden and A. Heijboer
Tue, 10 May 22
5/70

Comments: 6 pages, 2 figures, VLVnT 2021 contribution

Spontaneous Peccei-Quinn symmetry breaking renders sterile neutrino, axion and $χ$boson to be candidates for dark matter particles [CL]

http://arxiv.org/abs/2012.04648


We study the Peccei-Quinn (PQ) symmetry of the sterile right-handed neutrino sector and the gauge symmetries of the Standard Model. Due to four-fermion interactions, spontaneous breaking of these symmetries at the electroweak scale generates top-quark Dirac mass and sterile-neutrino Majorana mass. The top quark channel yields massive Higgs, $W^\pm$ and $Z^0$ bosons. The sterile neutrino channel yields the heaviest sterile neutrino Majorana mass, sterile Nambu-Goldstone axion (or majoron) and massive scalar $\chi$boson. Four-fermion operators effectively induce their tiny couplings to SM particles. We show that a sterile QCD axion is the PQ solution to the strong CP problem. The lightest and heaviest sterile neutrinos ($m_N^e\sim 10^2$ keV and $m_N^\tau\sim 10^2$ GeV), a sterile QCD axion ($m_a< 10^{-8}$ eV, $g_{a\gamma}< 10^{-13} {\rm GeV}^{-1}$) and a Higgs-like $\chi$boson ($m_\chi\sim 10^2$ GeV) can be dark matter particle candidates, for the constraints of their tiny couplings and long lifetimes inferred from the $W$-boson decay width, Xenon1T and precision fine-structure-constant experiments. The axion and $\chi$boson couplings to SM particles are below the values reached by current laboratory experiments and astrophysical observations for directly or indirectly detecting dark matter particles.

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S. Xue
Tue, 10 May 22
24/70

Comments: The final version appears in Nuclear Physics B

Multi-messenger High-Energy Signatures of Decaying Dark Matter and the Effect of Background Light [HEAP]

http://arxiv.org/abs/2205.03416


The IceCube Neutrino Observatory at the South Pole has measured astrophysical neutrinos using through-going and starting events in the TeV to PeV energy range. The origin of these astrophysical neutrinos is still largely unresolved, and among their potential sources could be dark matter decay. Measurements of the astrophysical flux using muon neutrinos are in slight tension with starting event measurements. This tension is driven by an excess observed in the energy range of 40-200 TeV with respect to the through-going expectation. Previous works have considered the possibility that this excess may be due to heavy dark matter decay and have placed constraints using gamma-ray and neutrino data. However, these constraints are not without caveats since they rely on the modeling of the astrophysical neutrino flux and the sources of gamma-ray emission. In this work, we derive background-agnostic galactic and extragalactic constraints on decaying dark matter by considering Tibet AS$_\gamma$ data, Fermi-LAT diffuse data, and the IceCube high-energy starting event sample. For the gamma-ray limits, we investigate the uncertainties on secondary emission from electromagnetic cascades during propagation arising from the unknown intensity of the extragalactic background light. We find that such uncertainties amount to a variation of up to $\sim 55\%$ in the gamma-ray limits derived with extragalactic data. Our results imply that a significant fraction of the astrophysical neutrino flux could be due to dark matter and that ruling it out depends on the assumptions on the gamma-ray and neutrino background. The latter depends on the yet unidentified sources.

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B. Skrzypek, M. Chianese and C. Delgado
Tue, 10 May 22
61/70

Comments: 22 pages

Stochastic effects on observation of ultralight bosonic dark matter [CEA]

http://arxiv.org/abs/2205.02960


Ultralight bosonic particles are fascinating candidates of dark matter (DM). It behaves as classical waves in our Galaxy due to its large number density. There have been various methods proposed to search for the wave-like DM, such as methods utilizing interferometric gravitational-wave detectors. Understanding the characteristics of DM signals is crucial to extract the properties of DM from data. While the DM signal is nearly monochromatic with the angular frequency of its mass, the amplitude and phase are gradually changing due to the velocity dispersion of DMs in our Galaxy halo. The stochastic amplitude and phase should be properly taken into account to accurately constrain the coupling constant of DM from data. Previous works formulated a method to obtain the upper bound on the coupling constant incorporating the stochastic effects. One of these works compared the upper bound with and without the stochastic effect in a measurement time that is much shorter than the variation time scale of the amplitude and phase. In this paper, we extend their formulation to arbitrary measurement time and evaluate the stochastic effects. Moreover, we investigate the velocity-dependent signal for dark photon DM including an uncertainly of the velocity. We demonstrate that our method accurately estimates the upper bound on the coupling constant with numerical simulations. We also estimate the expected upper bound of the coupling constant of axion DM and dark photon DM from future experiments in a semi-analytic way. The stochasticity especially affects constraints on a small mass region. Our formulation offers a generic treatment of the ultralight bosonic DM signal with the stochastic effect.

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H. Nakatsuka, S. Morisaki, T. Fujita, et. al.
Mon, 9 May 22
59/63

Comments: 23 pages, 13 figures

High-energy reconstruction for single and double cascades using the KM3NeT detector [IMA]

http://arxiv.org/abs/2205.02641


The discovery of a high-energy cosmic neutrino flux has paved the way for the field of neutrino astronomy. For a large part of the flux, the sources remain unidentified. The KM3NeT detector, which is under construction in the Mediterranean sea, is designed to determine their origin. KM3NeT will instrument a cubic kilometre of seawater with photomultiplier tubes that detect Cherenkov radiation from neutrino interaction products with nanosecond precision. For single cascade event signatures, KM3NeT already showed that it can reach degree-level resolutions, greatly increasing the use of these neutrinos for astronomy. In this contribution, we further refine the cascade reconstruction by making a more detailed model of the neutrinos events and including additional information on the hit times. The arrival time of light can be used to improve the identification of double cascade signatures from tau neutrinos, and the angular resolution of both single and double cascade signatures. Sub-degree resolution is achieved in both cases.

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T. Eeden, J. Seneca and A. Heijboer
Fri, 6 May 22
22/55

Comments: 10 pages, 5 figures, ICRC 2021 contribution

Inverse Tritium Beta Decay with Relic Neutrinos, Solar Neutrinos, and a 51Cr Source [CL]

http://arxiv.org/abs/2205.02363


The inverse tritium beta decay (ITBD) reaction, $\nu_e + ^3$H $\to e^- + ^3$He, is a promising experimental tool for observing relic neutrinos created in the early Universe. This reaction has been selected by the PTOLEMY experiment for the search of relic neutrinos. Despite its potential, the ITBD reaction induced by any sources of neutrinos has yet to be observed. We show that an intense $^{51}$Cr radioactive neutrino source is suitable for observing the ITBD reaction for the first time. As the Sun is another source of intense electron neutrinos, we also examine the ITBD reaction rate from solar neutrinos. Based on our recent studies on the evolution of the helicity of relic neutrinos, we further present the ITBD rate for capturing relic neutrinos as a function of neutrino mass hierarchy, the Dirac versus Majorana nature of neutrino, and the mass of the lightest neutrino.

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J. Peng and G. Baym
Fri, 6 May 22
25/55

Comments: 5 pages, 4 figures

Neutrino Portals, Terrestrial Upscattering, and Atmospheric Neutrinos [CL]

http://arxiv.org/abs/2205.02234


We consider the upscattering of atmospheric neutrinos in the interior of the Earth producing heavy neutral leptons (HNLs) which subsequently decay inside large volume detectors (e.g. Super-Kamiokande or DUNE). We compute the flux of upscattered HNLs arriving at a detector, and the resultant event rate of visible decay products. Using Super-Kamiokande’s atmospheric neutrino dataset we find new leading constraints for dipole couplings to any flavor with HNL masses between roughly 10 MeV and 100 MeV. For mass mixing with tau neutrinos, we probe new parameter space near HNL masses of $\sim 20$ MeV with prospects for substantial future improvements. We also discuss prospects at future experiments such as DUNE, JUNO, and Hyper-Kamiokande.

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R. Gustafson, R. Plestid and I. Shoemaker
Fri, 6 May 22
50/55

Comments: 12 pages + 4 pages appendices, 10 figures

Anisotropic cosmic optical background bound for decaying dark matter in light of the LORRI anomaly [CL]

http://arxiv.org/abs/2205.01079


Recently anomalous flux in the cosmic optical background (COB) is reported by the New Horizon observations. The COB flux is $16.37\pm1.47\, \rm nW m^{-2} sr^{-1}$, at the LORRI pivot wavelength of $0.608\,\rm \mu m$, which is $\sim 4\sigma$ level above the expected flux from the Hubble Space Telescope (HST) galaxy count. It would be great if this were a hint for the eV scale dark matter decaying into photons. In this paper, we point out that such a decaying dark matter model predicts a substantial amount of anisotropy in the COB flux, which is accurately measured by the HST. The data of the HST excludes the decay rate of the dominant cold dark matter larger than $10^{-24}$-$10^{-23}\,{\rm s}^{-1}$ in the mass range of $5$-$20\,$eV. As a result, the decaying cold dark matter explaining the COB excess is excluded by the anisotropy bound. We discuss some loopholes: e.g. warm/hot dark matter or two-step decay of the dark matter to explain the COB excess.

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K. Nakayama and W. Yin
Tue, 3 May 22
25/82

Comments: 18 pages, 4 figures

Timing and Multi-Channel: Novel Method for Determining the Neutrino Mass Ordering from Supernovae [CL]

http://arxiv.org/abs/2204.13135


One of the few remaining unknowns in the standard three-flavor neutrino oscillation paradigm is the ordering of neutrino masses. In this work we propose a novel method for determining neutrino mass ordering using the time information on early supernova neutrino events. In a core-collapse supernova, neutrinos are produced earlier than antineutrinos and, depending on the mass ordering which affects the adiabatic flavor evolution, may cause earlier observable signals in $\nu_e$ detection channels than in others. Hence, the time differences are sensitive to the mass ordering. We find that using the time information on the detection of the first galactic supernova events at future detectors like DUNE, JUNO and Hyper-Kamiokande, the mass ordering can already be determined at 2$\sigma$ CL, while $\mathcal{O}(10)$ events suffice for the discovery. Our method does not require high-statistics and could be used within the supernova early warning system (SNEWS) which will have access to the time information on early supernova neutrino events recorded in a number of detectors. The method proposed in this paper also implies a crucial interplay between the mass ordering and the triangulation method for locating supernovae.

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V. Brdar and X. Xu
Fri, 29 Apr 22
19/57

Comments: 13 pages, 5 figures

Search for supernova neutrinos and constraint on the galactic star formation rate with the KamLAND data [HEAP]

http://arxiv.org/abs/2204.12065


We present the results of a search for core-collapse supernova neutrinos, using long-term KamLAND data from 2002 March 9th to 2020 April 25th. We focus on the electron anti-neutrinos emitted from supernovae in the energy range of 1.8–111 MeV. Supernovae will make a neutrino event cluster with the length of $\sim$10 s in the KamLAND data. We find no neutrino clusters and give the upper limit on the supernova rate as to be 0.15 yr$^{-1}$ with a 90% confidence level. The detectable range, which corresponds to a >95% detection probability, is 40–59 kpc and 65–81 kpc for core-collapse supernovae and failed core-collapse supernovae, respectively. This paper proposes to convert the supernova rate obtained by the neutrino observation to the galactic star formation rate. Assuming a modified Salpter-type initial mass function, the upper limit on the galactic star formation rate is <17.5–22.7 (8.1–10.5) $M_{\odot} \mathrm{yr}^{-1}$ with a 90% (68.3%) confidence level.

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S. Abe, S. Asami, M. Eizuka, et. al.
Wed, 27 Apr 22
18/68

Comments: 10 pages, 4 figures

Results on photon-mediated dark matter-nucleus interactions from the PICO-60 C$_{3}$F$_{8}$ bubble chamber [CEA]

http://arxiv.org/abs/2204.10340


Many compelling models predict dark matter coupling to the electromagnetic current through higher multipole interactions, while remaining electrically neutral. Different multipole couplings have been studied, among them anapole moment, electric and magnetic dipole moments, and millicharge. This study sets limits on the couplings for these photon-mediated interactions using non-relativistic contact operators in an effective field theory framework. Using data from the PICO-60 bubble chamber leading limits for dark matter masses between 2.7 GeV/c$^2$ and 24 GeV/c$^2$ are reported for the coupling of these photon-mediated dark matter-nucleus interactions. The detector was filled with 52 kg of C$_3$F$_8$ operating at thermodynamic thresholds of 2.45 keV and 3.29 keV, reaching exposures of 1404 kg-day and 1167 kg-day, respectively.

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B. Ali, I. Arnquist, D. Baxter, et. al.
Mon, 25 Apr 22
5/36

Comments: N/A

SciTS: A Benchmark for Time-Series Database in Scientific Experiments and Industrial Internet of Things [CL]

http://arxiv.org/abs/2204.09795


Time-series data has an increasingly growing usage in Industrial Internet of Things (IIoT) and large-scale scientific experiments. Managing time-series data needs a storage engine that can keep up with their constantly growing volumes while providing an acceptable query latency. While traditional ACID databases favor consistency over performance, many time-series databases with novel storage engines have been developed to provide better ingestion performance and lower query latency. To understand how the unique design of a time-series database affects its performance, we design SciTS, a highly extensible and parameterizable benchmark for time-series data. The benchmark studies the data ingestion capabilities of time-series databases especially as they grow larger in size. It also studies the latencies of 5 practical queries from the scientific experiments use case. We use SciTS to evaluate the performance of 4 databases of 4 distinct storage engines: ClickHouse, InfluxDB, TimescaleDB, and PostgreSQL.

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J. Mostafa, S. Wehbi, S. Chilingaryan, et. al.
Fri, 22 Apr 22
51/64

Comments: N/A

Singlet-Doublet Fermion Origin of Dark Matter, Neutrino Mass and W-Mass Anomaly [CL]

http://arxiv.org/abs/2204.09671


Motivated by the recently reported anomaly in W boson mass by the CDF collaboration with $7\sigma$ statistical significance, we consider a singlet-doublet (SD) fermion dark matter (DM) model where the required correction to W boson mass arises from radiative corrections induced by DM fermions. While a single generation of SD fermions, odd under an ubroken $Z_2$ symmetry, lead to a tiny parameter space with DM mass near the standard model Higgs resonance which is consistent with DM phenomenology and enhanced W boson mass, two generations of SD fermions lead to a much wider DM parameter space with heavier generation playing the dominant role in W-mass correction. Additionally, such multiple generations of singlet-doublet fermions can also generate light neutrino masses radiatively if a $Z_2$-odd singlet scalar is included.

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D. Borah, S. Mahapatra and N. Sahu
Thu, 21 Apr 22
23/73

Comments: N/A

Detecting High-Energy Neutrino Minibursts from Local Supernovae with Multiple Neutrino Observatories [HEAP]

http://arxiv.org/abs/2204.08518


Growing evidence from multiwavelength observations of extragalactic supernovae (SNe) has established the presence of dense circumstellar material in Type II SNe. Interaction between the SN ejecta and the circumstellar material should lead to the acceleration of cosmic rays and associated high-energy emission. Observation of high-energy neutrinos along with the MeV neutrinos from SNe will provide unprecedented opportunities to understand unanswered questions in cosmic-ray and neutrino physics. We show that current and future neutrino detectors can identify high-energy neutrinos from an extragalactic SN in the neighborhood of the Milky Way. We present the prospects for detecting high-energy neutrino minibursts from SNe in known local galaxies, and demonstrate how the future high-energy neutrino network will extend the edge for identification of SN neutrinos.

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A. Kheirandish and K. Murase
Wed, 20 Apr 22
39/62

Comments: N/A

Type II Dirac Seesaw with Observable $ΔN_{\rm eff}$ in the light of W-mass Anomaly [CL]

http://arxiv.org/abs/2204.08266


We propose a type II seesaw model for light Dirac neutrinos to provide an explanation for the recently reported anomaly in W boson mass by the CDF collaboration with $7\sigma$ statistical significance. In the minimal model, the required enhancement in W boson mass is obtained at tree level due to the vacuum expectation value of a real scalar triplet, which also plays a role in generating light Dirac neutrino mass. Depending upon the couplings and masses of newly introduced particles, we can have thermally or non-thermally generated relativistic degrees of freedom $\Delta N_{\rm eff}$ in the form of right handed neutrinos which can be observed at future cosmology experiments. Extending the model to a radiative Dirac seesaw scenario can also accommodate dark matter and lepton anomalous magnetic moment.

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D. Borah, S. Mahapatra, D. Nanda, et. al.
Tue, 19 Apr 22
22/52

Comments: 8 pages, 9 figures

Investigating the sources of low-energy events in a SuperCDMS-HVeV detector [CL]

http://arxiv.org/abs/2204.08038


Recent experiments searching for sub-GeV/$c^2$ dark matter have observed event excesses close to their respective energy thresholds. Although specific to the individual technologies, the measured excess event rates have been consistently reported at or below event energies of a few-hundred eV, or with charges of a few electron-hole pairs. In the present work, we operated a 1-gram silicon SuperCDMS-HVeV detector at three voltages across the crystal (0 V, 60 V and 100 V). The 0 V data show an excess of events in the tens of eV region. Despite this event excess, we demonstrate the ability to set a competitive exclusion limit on the spin-independent dark matter–nucleon elastic scattering cross section for dark matter masses of $\mathcal{O}(100)$ MeV/$c^2$, enabled by operation of the detector at 0 V potential and achievement of a very low $\mathcal{O}(10)$ eV threshold for nuclear recoils. Comparing the data acquired at 0 V, 60 V and 100 V potentials across the crystal, we investigated possible sources of the unexpected events observed at low energy. The data indicate that the dominant contribution to the excess is consistent with a hypothesized luminescence from the printed circuit boards used in the detector holder.

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S. Collaboration, M. Albakry, I. Alkhatib, et. al.
Tue, 19 Apr 22
37/52

Comments: N/A

Independent determination of the Earth's orbital parameters with solar neutrinos in Borexino [CL]

http://arxiv.org/abs/2204.07029


Since the beginning of 2012, the Borexino collaboration has been reporting precision measurements of the solar neutrino fluxes, emitted in the proton-proton chain and in the Carbon-Nitrogen-Oxygen cycle. The experimental sensitivity achieved in Phase-II and Phase-III of the Borexino data taking made it possible to detect the annual modulation of the solar neutrino interaction rate due to the eccentricity of Earth’s orbit, with a statistical significance greater than 5$\sigma$. This is the first precise measurement of the Earth’s orbital parameters based solely on solar neutrinos and an additional signature of the solar origin of the Borexino signal. The complete periodogram of the time series of the Borexino solar neutrino detection rate is also reported, exploring frequencies between one cycle/year and one cycle/day. No other significant modulation frequencies are found. The present results were uniquely made possible by Borexino’s decade-long high-precision solar neutrino detection.

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S. Appel, Z. Bagdasarian, D. Basilico, et. al.
Fri, 15 Apr 22
32/50

Comments: 12 pages, 10 figures

Normal and Reverse Annual Modulations of Elastic WIMP-Nucleus Scattering Signals [CL]

http://arxiv.org/abs/2204.06458


Following our earlier work on the 3-dimensional effective velocity distribution of Galactic WIMPs (not only impinging on our detectors but also) scattering off target nuclei, in this paper, we demonstrate the normal and a “reverse” annual modulations of elastic WIMP-nucleus scattering signals, which could be observed in direct Dark Matter detection experiments. Our simulations show that, once the WIMP mass is as light as only a few tens GeV, the event number and the accumulated recoil energy of WIMP-induced scattering events off both of light and heavy target nuclei would indeed be maximal (minimal) in summer (winter). However, once the WIMP mass is as heavy as a few hundreds GeV, the event number and the accumulated recoil energy of WIMP scattering events off heavy nuclei would inversely be minimal in summer. Understandably, for an intermediate WIMP mass, the event number and the accumulated recoil energy of scattering events off some middle-mass nuclei would show an approximately uniform time dependence.

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C. Shan
Thu, 14 Apr 22
27/62

Comments: 10 pages, 7 figures

The ultra-high-energy neutrino-nucleon cross section: measurement forecasts for an era of cosmic EeV-neutrino discovery [CL]

http://arxiv.org/abs/2204.04237


Neutrino interactions with protons and neutrons probe their deep structure and may reveal new physics. The higher the neutrino energy, the sharper the probe. So far, the neutrino-nucleon ($\nu N$) cross section is known across neutrino energies from a few hundred MeV to a few PeV. Soon, ultra-high-energy (UHE) cosmic neutrinos, with energies above 100 PeV, could take us farther. So far, they have evaded discovery, but upcoming UHE neutrino telescopes endeavor to find them. We present the first detailed measurement forecasts of the UHE $\nu N$ cross section, geared to IceCube-Gen2, one of the leading detectors under planning. We use state-of-the-art ingredients in every stage of our forecasts: in the UHE neutrino flux predictions, the neutrino propagation inside Earth, the emission of neutrino-induced radio signals in the detector, their propagation and detection, and the treatment of backgrounds. After 10 years, if at least a few tens of UHE neutrino-induced events are detected, IceCube-Gen2 could measure the $\nu N$ cross section at center-of-mass energies of $\sqrt{s} \approx 10-100$ TeV for the first time, with a precision comparable to that of its theory prediction.

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V. Valera, M. Bustamante and C. Glaser
Tue, 12 Apr 22
1/87

Comments: 32 pages, 21 figures, 2 tables, plus appendix and references

Singlet extensions and W boson mass in the light of the CDF II result [CL]

http://arxiv.org/abs/2204.04770


Recently, the CDF collaboration has reported the precise measurement of the W boson mass, $M_W = 80433.5\pm 9.4 \,$MeV, based on $8.8$ fb$^{-1}$ of $\sqrt{s}=1.96$ TeV $p\bar{p}$ collision data from the CDF II detector at the Fermilab Tevatron. This is about $7\sigma$ away from the Standard Model prediction, $M_{W}^{\rm SM}=80357 \pm 6 \,$MeV. Such a large discrepancy may be partially due to exotic particles that radiatively alter the relation between the W and Z boson masses. In this Letter, we study singlet extensions of the Standard Model focusing on the shift of the W boson mass. In the minimal extension with a real singlet field, using the bounds from the electroweak oblique parameters, B meson decays, LEP, and LHC, we find that the W boson mass shift is at most a few MeV, and therefore it does not alleviate the tension between the CDF II result and the SM prediction. We then examine how much various bounds are relaxed when the singlet is allowed to decay invisibly and find that the increase of the W boson mass does not exceed $5$ MeV due to the bound from the Higgs signal strength. We also discuss phenomenological and cosmological implications of the singlet extensions such as the muon $g-2$ anomaly, axion/hidden photon dark matter, and self-interacting dark radiation as a possible alleviation of the Hubble tension.

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K. Sakurai, F. Takahashi and W. Yin
Tue, 12 Apr 22
68/87

Comments: 8 pages, 2 figures

Fingerprints of freeze-in dark matter in an early matter-dominated era [CL]

http://arxiv.org/abs/2204.03670


We study the impact of an alternate cosmological history with an early matter-dominated epoch on the freeze-in production of dark matter. Such early matter domination is triggered by a meta-stable matter field dissipating into radiation. In general, the dissipation rate has a non-trivial temperature and scale factor dependence. Compared to the usual case of dark matter production via the freeze-in mechanism in a radiation-dominated universe, in this scenario, orders of magnitude larger coupling between the visible and the dark sector can be accommodated. Finally, as a proof of principle, we consider a specific model where the dark matter is produced by a sub-GeV dark photon having a kinetic mixing with the Standard Model photon. We point out that the parameter space of this model can be probed by the experiments in the presence of an early matter-dominated era.

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A. Banerjee and D. Chowdhury
Mon, 11 Apr 22
16/61

Comments: 15 pages, 3 captioned figures. Comments are welcome

Search for 70 μeV Dark Photon Dark Matter with a Dielectrically-Loaded Multi-Wavelength Microwave Cavity [CL]

http://arxiv.org/abs/2204.03818


Microwave cavities have been deployed to search for bosonic dark matter candidates with masses of a few $\mu$eV. However, the sensitivity of these cavity detectors is limited by their volume, and the traditionally-employed half-wavelength cavities suffer from a significant volume reduction at higher masses. ADMX-Orpheus mitigates this issue by operating a tunable, dielectrically-loaded cavity at a higher-order mode, which allows the detection volume to remain large. The ADMX-Orpheus inaugural run excludes dark photon dark matter with kinetic mixing angle $\chi > 10^{-13}$ between 65.5 $\mu$eV (15.8 GHz) and 69.3 $\mu$eV 16.8GHz), marking the first tunable microwave cavity dark matter search beyond 7.3 GHz.

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R. Cervantes, G. Carosi, C. Hanretty, et. al.
Mon, 11 Apr 22
18/61

Comments: N/A

Snowmass2021 Cosmic Frontier White Paper: Enabling Flagship Dark Energy Experiments to Reach their Full Potential [CEA]

http://arxiv.org/abs/2204.01992


A new generation of powerful dark energy experiments will open new vistas for cosmology in the next decade. However, these projects cannot reach their utmost potential without data from other telescopes. This white paper focuses in particular on the compelling benefits of ground-based spectroscopic and photometric observations to complement the Vera C. Rubin Observatory, as well as smaller programs in aid of a DESI-2 experiment and CMB-S4. These additional data sets will both improve dark energy constraints from these flagship projects beyond what would possible on their own and open completely new windows into fundamental physics. For example, additional photometry and single-object spectroscopy will provide necessary follow-up information for supernova and strong lensing cosmology, while highly-multiplexed spectroscopy both from smaller facilities over wide fields and from larger facilities over narrower regions of sky will yield more accurate photometric redshift estimates for weak lensing and galaxy clustering measurements from the Rubin Observatory, provide critical spectroscopic host galaxy redshifts for supernova Hubble diagrams, provide improved understanding of limiting astrophysical systematic effects, and enable new measurements that probe the nature of gravity. A common thread is that access to complementary data from a range of telescopes/instruments would have a substantial impact on the rate of advance of dark energy science in the coming years.

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J. Blazek, D. Clowe, T. Collett, et. al.
Wed, 6 Apr 22
68/68

Comments: White paper submitted to the Proceedings of the US Community Study on the Future of Particle Physics (Snowmass 2021)

Searching for axion-like time-dependent cosmic birefringence with SPT-3G [CEA]

http://arxiv.org/abs/2203.16567


Ultralight axion-like particles (ALPs) are compelling dark matter candidates because of their potential to resolve small-scale discrepancies between $\Lambda$CDM predictions and cosmological observations. Axion-photon coupling induces a polarization rotation in linearly polarized photons traveling through an ALP field; thus, as the local ALP dark matter field oscillates in time, distant static polarized sources will appear to oscillate with a frequency proportional to the ALP mass. We use observations of the cosmic microwave background from SPT-3G, the current receiver on the South Pole Telescope, to set upper limits on the value of the axion-photon coupling constant $g_{\phi\gamma}$ over the approximate mass range $10^{-22} – 10^{-19}$ eV, corresponding to oscillation periods from 12 hours to 100 days. For periods between 1 and 100 days ($4.7 \times 10^{-22} \text{ eV} \leq m_\phi \leq 4.7 \times 10^{-20} \text{ eV}$), where the limit is approximately constant, we set a median 95% C.L. upper limit on the amplitude of on-sky polarization rotation of 0.071 deg. Assuming that dark matter comprises a single ALP species with a local dark matter density of $0.3 \text{ GeV/cm}^3$, this corresponds to $g_{\phi\gamma} < 1.18 \times 10^{-12}\text{ GeV}^{-1} \times \left( \frac{m_{\phi}}{1.0 \times 10^{-21} \text{ eV}} \right)$. These new limits represent an improvement over the previous strongest limits set using the same effect by a factor of ~3.8.

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K. Ferguson, A. Anderson, N. Whitehorn, et. al.
Fri, 1 Apr 22
56/85

Comments: 16 pages, 5 figures, to be submitted to Physical Review D

T-RAX: Transversely Resonant Axion eXperiment [IMA]

http://arxiv.org/abs/2203.15487


We propose to use an elongated rectangular waveguide near its cutoff frequency for axionic dark matter searches. The detector’s large surface area allows for significant signal power, while its narrow transverse dimension and tapered-waveguide coupling suppress parasitic modes. The proposed system can fit inside a solenoid magnet and is sensitive to the QCD-axion in the axion mass $40-400\,\mu$eV. We describe the theoretical principles of the new design, present simulation results, and discuss the implementation.

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C. Lee and O. Reimann
Wed, 30 Mar 22
62/77

Comments: N/A

Constraints on light Dark Matter evaporated from Primordial Black Hole through electron targets [CL]

http://arxiv.org/abs/2203.14443


Light sub-GeV dark matter (DM) particles in the Milky Way or macroscopic objects such as primordial black holes (PBHs) become attractive DM candidates due to null results of WIMP from direct detection experiments. We explore the possibility in which the present PBHs play as a novel source to produce light boosted DM and confine light PBHs with current and future terrestrial facilities. We study the electron elastic scattering data and obtain the current constraints from Super-Kamiokande and XENON1T on the boosted DM from PBH evaporation. The prospective bounds on the sub-GeV DM-electron scattering cross section and the fraction of DM composed of PBHs $f_{\rm PBH}$ are also imposed for future Xenon experiments.

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T. Li and J. Liao
Tue, 29 Mar 22
1/73

Comments: 6 pages, 3 figures

New Horizons: Scalar and Vector Ultralight Dark Matter [CL]

http://arxiv.org/abs/2203.14915


The last decade has seen unprecedented effort in dark matter model building at all mass scales coupled with the design of numerous new detection strategies. Transformative advances in quantum technologies have led to a plethora of new high-precision quantum sensors and dark matter detection strategies for ultralight ($<10\,$eV) bosonic dark matter that can be described by an oscillating classical, largely coherent field. This white paper focuses on searches for wavelike scalar and vector dark matter candidates.

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D. Antypas, A. Banerjee, C. Bartram, et. al.
Tue, 29 Mar 22
28/73

Comments: Snowmass 2021 White Paper

Axion Dark Matter [CL]

http://arxiv.org/abs/2203.14923


Axions are well-motivated dark matter candidates with simple cosmological production mechanisms. They were originally introduced to solve the strong CP problem, but also arise in a wide range of extensions to the Standard Model. This Snowmass white paper summarizes axion phenomenology and outlines next-generation laboratory experiments proposed to detect axion dark matter. There are vibrant synergies with astrophysical searches and advances in instrumentation including quantum-enabled readout, high-Q resonators and cavities and large high-field magnets. This white paper outlines a clear roadmap to discovery, and shows that the US is well-positioned to be at the forefront of the search for axion dark matter in the coming decade.

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C. Adams, A. Agrawal, R. Balafendiev, et. al.
Tue, 29 Mar 22
33/73

Comments: N/A

Exploration of Wire Array Metamaterials for the Plasma Axion Haloscope [CL]

http://arxiv.org/abs/2203.13945


A plasma haloscope has recently been proposed as a feasible approach to extend the search for dark matter axions above 10 GHz ($\sim$ 40 $\mu$eV), whereby the microwave cavity in a conventional axion haloscope is supplanted by a wire array metamaterial. As the plasma frequency of a metamaterial is determined by its unit cell, and is thus a bulk property, a metamaterial resonator of any frequency can be made arbitrarily large, in contrast to a microwave cavity which incurs a steep penalty in volume with increasing frequency. We have investigated the basic properties of wire array metamaterials through $S_{21}$ measurements in the 10 GHz range. Excellent agreement with theoretical models is found, by which we project achievable quality factors to be of order $10^{4}$ in an actual axion search. Furthermore, schemes for tuning the array over a usable dynamic range ($30\%$ in frequency) appear practical from an engineering perspective.

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M. Wooten, A. Droster, A. Kenany, et. al.
Tue, 29 Mar 22
55/73

Comments: to be submitted to Physical Review Letters

PeV Tau Neutrinos to Unveil Ultra-High-Energy Sources [HEAP]

http://arxiv.org/abs/2203.13827


The observation of ultra-high-energy EeV-energy cosmogenic neutrinos provides a direct path to identifying the sources of the highest energy cosmic rays; searches have so far resulted in only upper limits on their flux. However, with the realization of cubic-kilometer detectors such as IceCube and, in the near future, KM3NeT, GVD-Baikal, and similar instruments, we anticipate the observation of PeV-energy cosmic neutrinos with high statistics. In this context, we draw attention to the opportunity to identify EeV tau neutrinos at PeV energy using Earth-traversing tau neutrinos. We show that Cherenkov detectors can improve their sensitivity to transient point sources by more than an order of magnitude by indirectly observing EeV tau neutrinos with initial energies that are nominally beyond their reach. This new technique also improves their sensitivity to the ultra-high-energy diffuse neutrino flux by up to a factor of two. Our work exemplifies how observing tau neutrinos at PeV energies provides an unprecedented reach to EeV fluxes.

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C. Argüelles, F. Halzen, A. Kheirandish, et. al.
Tue, 29 Mar 22
63/73

Comments: 5 pages, 2 figures

Relic gravitons at intermediate frequencies and the expansion history of the Universe [CL]

http://arxiv.org/abs/2203.13586


The early expansion history of the Universe is constrained by combining the most recent limits on the cosmic gravitons in the audio band and the claimed evidences of the nHz domain. The simplest scenario stipulates that between the end of inflation and the formation of light nuclei the evolution consists of a single phase expanding at a rate that is either faster or slower than the one of radiation. If there are instead multiple post-inflationary stages evolving at different rates, the spectral energy density always undershoots the signals potentially attributed to relic gravitons by the pulsar timing arrays at intermediate frequencies but ultimately develops a local maximum. After examining further complementary possibilities (like the presence of a secondary stage of inflation at low-scales) we analyze the early modifications of the effective expansion rate and argue that if the refractive index of the relic gravitons increases during a conventional inflationary epoch the spectral energy density is blue above the fHz and then flattens out in the $\mu$Hz region. In this instance the signal is compatible with the unconfirmed nHz observations, with the most recent limits of the wide-band interferometers and with the further constraints customarily imposed on the backgrounds of relic gravitons produced during inflation.

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M. Giovannini
Mon, 28 Mar 22
24/50

Comments: 37 pages, 16 figures

Direct Search for Dark Matter Axions Excluding ALP Cogenesis in the 63-67 micro-eV Range, with The ORGAN Experiment [CL]

http://arxiv.org/abs/2203.12152


The standard model axion seesaw Higgs portal inflation (SMASH) model is a well motivated, self-contained description of particle physics over a range of energy scales that predicts axion dark matter particles to exist within the mass range of $50-200\,\mu$eV. To scan these masses an axion haloscope under a strong constant magnetic field must operate between 12 to 48 GHz. The ORGAN experiment (situated in Perth, Australia) is a microwave cavity axion haloscope that aims to search the majority of the mass range predicted by the SMASH model. Here we present results of Phase 1a, the first experiment to scan and search for axions in the microwave Ku Band. Our initial scan sets a new limit on the coupling of axions to two photons of $g_{a\gamma\gamma}\geq 3\times 10^{-12}\, \textrm{GeV}^{-1}$ over the mass range $63.2$ to $67.1~\mu$eV with $95\%$ confidence. This result is the most sensitive to date in this mass range, sufficient to exclude the well motivated ALP (Axion Like Particle) cogenesis model for dark matter, which adds ALPs to the standard model in the early universe to simultaneously explain the observed baryon and dark matter densities. To attain this level of sensitivity we utilised a TM$_{010}$ cylindrical cavity resonator, scanned between 15.28 to 16.23 GHz through the utilisation of a tuning rod. Measurements were performed over a duration of 3.5 weeks with a $74\%$ duty cycle, with the resonator coupled to a low noise HEMT amplifier and placed inside a superconducting solenoidal electromagnet of 11.5 Tesla in magnetic field strength.

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A. Quiskamp, B. McAllister, P. Altin, et. al.
Fri, 25 Mar 22
6/46

Comments: N/A

Hadrophilic Light Dark Matter from the Atmosphere [CL]

http://arxiv.org/abs/2203.12630


Light sub-GeV dark matter (DM) constitutes an underexplored target, beyond the optimized sensitivity of typical direct DM detection experiments. We comprehensively investigate hadrophilic light DM produced from cosmic-ray collisions with the atmosphere. The resulting relativistic DM, originating from meson decays, can be efficiently observed in variety of experiments, such as XENON1T. We include for the first time decays of $\eta$, $\eta^{\prime}$ and $K^+$ mesons, leading to improved limits for DM masses above few hundred MeV. We incorporate an exact treatment of the DM attenuation in Earth and demonstrate that nuclear form factor effects can significantly impact the resulting testable DM parameter space. Further, we establish projections for upcoming experiments, such as DARWIN, over a wide range of DM masses below the GeV scale.

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C. Argüelles, V. Muñoz, I. Shoemaker, et. al.
Fri, 25 Mar 22
25/46

Comments: 7 pages, 4 figures

Rocks, Water and Noble Liquids: Unfolding the Flavor Contents of Supernova Neutrinos [CL]

http://arxiv.org/abs/2203.12696


Measuring core-collapse supernova neutrinos, both from individual supernovae within the Milky Way and from past core collapses throughout the Universe (the diffuse supernova neutrino background, or DSNB), is one of the main goals of current and next generation neutrino experiments. Detecting the heavy-lepton flavor (muon and tau types, collectively $\nu_x$) component of the flux is particularly challenging due to small statistics and large backgrounds. While the next galactic neutrino burst will be observed in a plethora of neutrino channels, allowing to measure a small number of $\nu_x$ events, only upper limits are anticipated for the diffuse $\nu_x$ flux even after decades of data taking with conventional detectors. However, paleo-detectors could measure the time-integrated flux of neutrinos from galactic core-collapse supernovae via flavor-blind neutral current interactions. In this work, we show how combining a measurement of the average galactic core-collapse supernova flux with paleo detectors and measurements of the DSNB electron-type neutrino fluxes with the next-generation water Cherenkov detector Hyper-Kamiokande and the liquid noble gas detector DUNE will allow to determine the mean supernova $\nu_x$ flux parameters with precision of order ten percent.

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S. Baum, F. Capozzi and S. Horiuchi
Fri, 25 Mar 22
35/46

Comments: 18 pages, 5 figures

Testing Non-Standard Interactions Between Solar Neutrinos and Quarks with Super-Kamiokande [CL]

http://arxiv.org/abs/2203.11772


Non-Standard Interactions (NSI) between neutrinos and matter affect the neutrino flavor oscillations. Due to the high matter density in the core of the Sun, solar neutrinos are suited to probe these interactions. Using the $277$ kton-yr exposure of Super-Kamiokande to $^{8}$B solar neutrinos, we search for the presence of NSI. Our data favors the presence of NSI with down quarks at 1.8$\sigma$, and with up quarks at 1.6$\sigma$, with the best fit NSI parameters being ($\epsilon_{11}^{d},\epsilon_{12}^{d}$) = (-3.3, -3.1) for $d$-quarks and ($\epsilon_{11}^{u},\epsilon_{12}^{u}$) = (-2.5, -3.1) for $u$-quarks. After combining with data from the Sudbury Neutrino Observatory and Borexino, the significance increases by 0.1$\sigma$.

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S. Collaboration, P. Weatherly, K. Abe, et. al.
Wed, 23 Mar 22
27/76

Comments: Author: Pierce Weatherly 25 pages. To be submitted to Physical Review D

Snowmass2021 Cosmic Frontier CF6 White Paper: Multi-Experiment Probes for Dark Energy — Transients [CEA]

http://arxiv.org/abs/2203.11226


This invited Snowmass 2021 White Paper highlights the power of joint-analysis of astronomical transients in advancing HEP Science and presents research activities that can realize the opportunities that come with current and upcoming projects. Transients of interest include gravitational wave events, neutrino events, strongly-lensed quasars and supernovae, and Type~Ia supernovae specifically. These transients can serve as probes of cosmological distances in the Universe and as cosmic laboratories of extreme strong-gravity, high-energy physics. Joint analysis refers to work that requires significant coordination from multiple experiments or facilities so encompasses Multi-Messenger Astronomy and optical transient discovery and distributed follow-up programs.

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A. Kim, A. Palmese, M. Pereira, et. al.
Wed, 23 Mar 22
37/76

Comments: Contribution to Snowmass 2021. Invited white paper from CF06. Comments and endorsers welcome

Scalar-mediated dark matter model at colliders and gravitational wave detectors — A White paper for Snowmass 2021 [CL]

http://arxiv.org/abs/2203.10046


The weakly interacting massive particles (WIMPs) have been the most popular particle dark matter (DM) candidate for the last several decades, and it is well known that WIMP can be probed via the direct, indirect and collider experiments. However, the direct and indirect signals are highly suppressed in some scalar-mediated DM models, e.g. the lepton portal model with a Majorana DM candidate. As a result, collider searches are considered as the only hope to probe such models. In this white paper, we propose that the gravitational wave (GW) astronomy also serves as a powerful tool to probe such scalar mediated WIMP models via the potential first-order phase transition GW signals. An example for the lepton portal dark matter is provided, showing the complementarity between collider and GW probes.

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J. Liu, X. Wang and K. Xie
Mon, 21 Mar 22
40/60

Comments: 4 pages + references, 2 figures, contribution to Snowmass 2021

The Mercedes water Cherenkov detector [CL]

http://arxiv.org/abs/2203.08782


The concept of a small, single-layer water Cherenkov detector, with three photomultiplier tubes (PMT), placed at its bottom in a $120^{\circ}$ star configuration (\emph{Mercedes} WCD) is presented. The PMTs are placed near the lateral walls of the stations with an adjustable inclination and may be installed inside or outside the water volume. To illustrate the technical viability of this concept and obtain a first-order estimation of its cost, an engineering design was elaborated. The sensitivity of these stations to low energy EAS electrons, photons and muons is discussed, both in compact and sparse array configurations. It is shown that the analysis of the intensity and time patterns of the PMT signals, using Machine Learning techniques, enables the tagging of muons, achieving an excellent gamma/hadron discrimination for TeV showers. This concept minimises the station production and maintenance costs, allowing for a highly flexible and fast installation. Mercedes WCDs are thus well-suited for use in high-altitude large gamma-ray observatories covering an extended energy range from the low energies, closing the gap between satellite and ground-based measurements, to very high energy regions, beyond the PeV scale.

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P. Assis, A. Bakalová, U. Almeida, et. al.
Thu, 17 Mar 22
6/66

Comments: 8 pages, 12 figures

A Strategy for Low-Mass Dark Matter Searches with Cryogenic Detectors in the SuperCDMS SNOLAB Facility [CL]

http://arxiv.org/abs/2203.08463


The SuperCDMS Collaboration is currently building SuperCDMS SNOLAB, a dark matter search focused on nucleon-coupled dark matter in the 1-5 GeV mass range. Looking to the future, the Collaboration has developed a set of experience-based upgrade scenarios, as well as novel directions, to extend the search for dark matter using the SuperCDMS technology in the SNOLAB facility. The experienced-based scenarios are forecasted to probe many square decades of unexplored dark matter parameter space below 5 GeV, covering over 6 decades in mass: 1-100 eV for dark photons and axion-like particles, 1-100 MeV for dark-photon-coupled light dark matter, and 0.05-5 GeV for nucleon-coupled dark matter. They will reach the neutrino fog in the 0.5-5 GeV mass range and test a variety of benchmark models and sharp targets. The novel directions involve greater departures from current SuperCDMS technology but promise even greater reach in the long run, and their development must begin now for them to be available in a timely fashion.
The experienced-based upgrade scenarios rely mainly on dramatic improvements in detector performance based on demonstrated scaling laws and reasonable extrapolations of current performance. Importantly, these improvements in detector performance obviate significant reductions in background levels beyond current expectations for the SuperCDMS SNOLAB experiment. Given that the dominant limiting backgrounds for SuperCDMS SNOLAB are cosmogenically created radioisotopes in the detectors, likely amenable only to isotopic purification and an underground detector life-cycle from before crystal growth to detector testing, the potential cost and time savings are enormous and the necessary improvements much easier to prototype.

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S. Collaboration, M. Albakry, I. Alkhatib, et. al.
Thu, 17 Mar 22
26/66

Comments: contribution to Snowmass 2021

Probing the Electroweak Phase Transition with Exotic Higgs Decays [CL]

http://arxiv.org/abs/2203.08206


An essential goal of the Higgs physics program at the LHC and beyond is to explore the nature of the Higgs potential and shed light on the mechanism of electroweak symmetry breaking. An important class of models defining the strength and order of the electroweak phase transition is driven by the Higgs boson coupling to a light new state. This Snowmass white paper points out the existence of a region of parameter space where a strongly first order electroweak phase transition is compatible with exotic decays of the SM-like Higgs boson. A dedicated search for exotic Higgs decays can actively explore this framework at the Large Hadron Collider (LHC), while future exotic Higgs decay searches at the high-luminosity LHC and future Higgs factories will be vital to conclusively probe the scenario.

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M. Carena, J. Kozaczuk, Z. Liu, et. al.
Thu, 17 Mar 22
27/66

Comments: 10 pages + references, 4 figures, Contribution to Snowmass 2021

Snowmass2021 Cosmic Frontier White Paper: Future Gravitational-Wave Detector Facilities [CL]

http://arxiv.org/abs/2203.08228


The next generation of gravitational-wave observatories can explore a wide range of fundamental physics phenomena throughout the history of the universe. These phenomena include access to the universe’s binary black hole population throughout cosmic time, to the universe’s expansion history independent of the cosmic distance ladders, to stochastic gravitational-waves from early-universe phase transitions, to warped space-time in the strong-field and high-velocity limit, to the equation of state of nuclear matter at neutron star and post-merger densities, and to dark matter candidates through their interaction in extreme astrophysical environments or their interaction with the detector itself. We present the gravitational-wave detector concepts than can drive the future of gravitational-wave astrophysics. We summarize the status of the necessary technology, and the research needed to be able to build these observatories in the 2030s.

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S. Ballmer, R. Adhikari, L. Badurina, et. al.
Thu, 17 Mar 22
28/66

Comments: 28 pages, 5 figures, contribution to Snowmass 2021

Constraints on Neutron-Mirror-Neutron Oscillation from Neutron Star Cooling [CL]

http://arxiv.org/abs/2203.08473


We address a method of limiting neutron-mirror neutron mixing ($\epsilon_{n n’}$) by analyzing its effect on neutron star (NS) heating. This method employs observational bounds on the surface temperature of NSs to constrain $\epsilon_{n n’}$. The obtained bound is so stringent that it would exclude any discovery of $n-n’$ oscillation by the planned terrestrial experiments. Motivated by this last crucially important fact, we critically analyze this suggestion and note a very interesting new effect present in nearly exact mirror models, which significantly affect this bound. The new element in our discussion is that in mirror models there is the $\beta$ decay $n’ \to p’+ e’ +\bar{\nu}’{e}$, which creates a cloud of mirror particles $n’$, $p’$, $e’$ and $D’$ inside the NS. The $e’$ can “rob” the energy generated by the $n \to n’$ transition from the NS. This is achieved via $e-e’$ scattering enabled by the presence of a (minute) milli-charge in mirror particles. This energy is emitted as unobserved mirror photons via fast mirror bremsstrahlung. This will lead to relaxing of the stringent bounds on $\epsilon{nn’}$.

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I. Goldman, R. Mohapatra, S. Nussinov, et. al.
Thu, 17 Mar 22
33/66

Comments: 22 pages, 2 figures

The Sanford Underground Research Facility [CL]

http://arxiv.org/abs/2203.08293


The Sanford Underground Research Facility (SURF) has been operating since 2007 supporting underground research in rare-process physics, as well as offering research opportunities in other disciplines. SURF laboratory facilities include a Surface Campus as well as campuses at the 4850-foot level (1500 m, 4300 m.w.e.) that host a range of significant physics experiments, including those studying dark matter, neutrino properties, and nuclear astrophysics topics. SURF is also home to the Long-Baseline Neutrino Facility (LBNF) that will host the international Deep Underground Neutrino Experiment (DUNE). SURF offers an ultra-low background environment, low-background assay capabilities, and electroformed copper is produced at the facility. SURF is proposing additional underground space on the 4850L and 7400L (2300 m, 6500 m.w.e.), and initial engineering designs have been completed. SURF is a dedicated research facility with significant expansion capability, and applications from new experiments are welcome.

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J. Heise
Thu, 17 Mar 22
40/66

Comments: Contribution to Snowmass 2021

Snowmass2021 Cosmic Frontier: The landscape of low-threshold dark matter direct detection in the next decade [CL]

http://arxiv.org/abs/2203.08297


The search for particle-like dark matter with meV-to-GeV masses has developed rapidly in the past few years. We summarize the science case for these searches, the recent progress, and the exciting upcoming opportunities. Funding for Research and Development and a portfolio of small dark matter projects will allow the community to capitalize on the substantial recent advances in theory and experiment and probe vast regions of unexplored dark-matter parameter space in the coming decade.

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R. Essig, G. Giovanetti, N. Kurinsky, et. al.
Thu, 17 Mar 22
46/66

Comments: Contribution to Snowmass 2021. Accepting comments, suggestions, and endorsers on google form linked in abstract on pdf until March 31, 2022

Snowmass2021 Cosmic Frontier White Paper: 21cm Radiation as a Probe of Physics Across Cosmic Ages [CEA]

http://arxiv.org/abs/2203.07864


The 21cm line refers to a forbidden transition in neutral hydrogen associated with alignment of spins of the proton and electron. It is a very low energy transition that is emitted whenever there is neutral hydrogen in the Universe. Since baryons are mostly (~75%) hydrogen, one can in principle detect this emission throughout much of the history of the Universe. The dominant emission mechanism is different across cosmic ages. Before the photons decouple from matter, hydrogen is in an ionized state and does not emit in 21cm. After recombination and during the Dark Ages, at z ~ 30-1000, the 21cm emission is associated with density fluctuations in the neutral hydrogen medium. After the first stars turn on and galaxies begin to form, the 21cm emission traces bubbles of ionized hydrogen in the sea of the neutral medium. This epoch, spanning z ~ 6-30, is often referred to as cosmic dawn and the Epoch of Reionization (EoR). At redshifts below z<6, the intergalactic medium is largely ionized, but pockets of self-shielded neutral gas form in dense galactic environments and 21cm emission traces the distribution of galaxies. The vastly different emission mechanisms allow us to probe very different physics at different redshifts, corresponding to different observational frequencies. The instrumental challenges, namely building very sensitive and exquisitely calibrated radio telescopes, however, share many commonalities across frequency bands. The potential of the 21cm probe has been recognized by the Decadal Survey of Astronomy & Astrophysics, whose Panel on Cosmology identified the Dark Ages as its sole discovery area. We argue that HEP should recognize the potential of 21cm as a probe of fundamental physics across many axes and invest in the technology development that will enable full exploitation of this rich technique.

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A. Liu, L. Newburgh, B. Saliwanchik, et. al.
Wed, 16 Mar 22
83/84

Comments: Snowmass 2021 Solicited White Paper by the Cosmic Frontier 5 Topical Group

Snowmass2021 Cosmic Frontier White Paper: High Density Galaxy Clustering in the Regime of Cosmic Acceleration [CEA]

http://arxiv.org/abs/2203.07291


Joint studies of imaging and spectroscopic samples, informed by theory and simulations, offer the potential for comprehensive tests of the cosmological model over redshifts z<1.5. Spectroscopic galaxy samples at these redshifts can be increased beyond the planned Dark Energy Spectroscopic Instrument (DESI) program by at least an order of magnitude, thus offering significantly more constraining power for these joint studies. Spectroscopic observations of these galaxies in the latter half of the 2020’s and beyond would leverage the theory and simulation effort in this regime. In turn, these high density observations will allow enhanced tests of dark energy, physics beyond the standard model, and neutrino masses that will greatly exceed what is currently possible. Here, we present a coordinated program of simulations, theoretical modeling, and future spectroscopy that would enable precise cosmological studies in the accelerating epoch where the effects of dark energy are most apparent.

Read this paper on arXiv…

K. Dawson, A. Hearin, K. Heitmann, et. al.
Tue, 15 Mar 22
42/108

Comments: Contribution to Snowmass 2022, CF04: Dark energy and cosmic acceleration: the modern universe

White Paper on Light Sterile Neutrino Searches and Related Phenomenology [CL]

http://arxiv.org/abs/2203.07323


This white paper provides a comprehensive review of our present understanding of experimental neutrino anomalies that remain unresolved, charting the progress achieved over the last decade at the experimental and phenomenological level, and sets the stage for future programmatic prospects in addressing those anomalies. It is purposed to serve as a guiding and motivational “encyclopedic” reference, with emphasis on needs and options for future exploration that may lead to the ultimate resolution of the anomalies. We see the main experimental, analysis, and theory-driven thrusts that will be essential to achieving this goal being: 1) Cover all anomaly sectors — given the unresolved nature of all four canonical anomalies, it is imperative to support all pillars of a diverse experimental portfolio, source, reactor, decay-at-rest, decay-in-flight, and other methods/sources, to provide complementary probes of and increased precision for new physics explanations; 2) Pursue diverse signatures — it is imperative that experiments make design and analysis choices that maximize sensitivity to as broad an array of these potential new physics signatures as possible; 3) Deepen theoretical engagement — priority in the theory community should be placed on development of standard and beyond standard models relevant to all four short-baseline anomalies and the development of tools for efficient tests of these models with existing and future experimental datasets; 4) Openly share data — Fluid communication between the experimental and theory communities will be required, which implies that both experimental data releases and theoretical calculations should be publicly available; and 5) Apply robust analysis techniques — Appropriate statistical treatment is crucial to assess the compatibility of data sets within the context of any given model.

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M. Acero, C. Argüelles, M. Hostert, et. al.
Tue, 15 Mar 22
45/108

Comments: Contribution to Snowmass 2021 by the NF02 Topical Group (Understanding Experimental Neutrino Anomalies)

Snowmass 2021 Community Survey Report [CL]

http://arxiv.org/abs/2203.07328


The Snowmass Community Survey was designed by the Snowmass Early Career (SEC) Survey Core Initiative team between April 2020 and June 2021, and released to the community on June 28, 2021. It aims to be a comprehensive assessment of the state of the high-energy particle and astrophysics (HEPA) community, if not the field, though the Snowmass process is largely based within the United States. Among other topics, some of the central foci of the Survey were to gather demographic, career, physics outlook, and workplace culture data on a large segment of the Snowmass community. With nearly $1500$ total interactions with the Survey, the SEC Survey team hopes the findings and discussions within this report will be of service to the community over the next decade. Some conclusions should reinforce the aspects of HEPA which are already functional and productive, while others should strengthen arguments for cultural and policy changes within the field.

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G. Agarwal, J. Barrow, M. Carneiro, et. al.
Tue, 15 Mar 22
53/108

Comments: Contribution to Snowmass 2021. Submitted by the Snowmass Early Career Survey Initiative

Snowmass 2021 White Paper: The Windchime Project [CL]

http://arxiv.org/abs/2203.07242


The absence of clear signals from particle dark matter in direct detection experiments motivates new approaches in disparate regions of viable parameter space. In this Snowmass white paper, we outline the Windchime project, a program to build a large array of quantum-enhanced mechanical sensors. The ultimate aim is to build a detector capable of searching for Planck mass-scale dark matter purely through its gravitational coupling to ordinary matter. In the shorter term, we aim to search for a number of other physics targets, especially some ultralight dark matter candidates. Here, we discuss the basic design, open R&D challenges and opportunities, current experimental efforts, and both short- and long-term physics targets of the Windchime project.

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W. Collaboration, A. Attanasio, S. Bhave, et. al.
Tue, 15 Mar 22
60/108

Comments: 8 pages, 3 figures. Contribution to the Snowmass 2021 proceedings (Cosmic Frontier working groups 1 and 2 – particle and wave-like dark matter)

Snowmass2021 Cosmic Frontier White Paper: Observational Facilities to Study Dark Matter [CEA]

http://arxiv.org/abs/2203.06200


We present an overview of future observational facilities that will significantly enhance our understanding of the fundamental nature of dark matter. These facilities span a range of observational techniques including optical/near-infrared imaging and spectroscopy, measurements of the cosmic microwave background, pulsar timing, 21-cm observations of neutral hydrogen at high redshift, and the measurement of gravitational waves. Such facilities are a critical component of a multi-pronged experimental program to uncover the nature of dark matter, while often providing complementary measurements of dark energy, neutrino physics, and inflation.

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S. Chakrabarti, A. Drlica-Wagner, T. Li, et. al.
Tue, 15 Mar 22
66/108

Comments: Contribution to Snowmass 2021. 31 pages, 6 figures, 2 tables

Snowmass2021 Cosmic Frontier: The landscape of cosmic-ray and high-energy photon probes of particle dark matter [CL]

http://arxiv.org/abs/2203.06894


This white paper discusses the current landscape and prospects for experiments sensitive to particle dark matter processes producing photons and cosmic rays. Much of the gamma-ray sky remains unexplored on a level of sensitivity that would enable the discovery of a dark matter signal. Currently operating GeV-TeV observatories, such as Fermi-LAT, atmospheric Cherenkov telescopes, and water Cherenkov detector arrays continue to target several promising dark matter-rich environments within and beyond the Galaxy. Soon, several new experiments will continue to explore, with increased sensitivity, especially extended targets in the sky. This paper reviews the several near-term and longer-term plans for gamma-ray observatories, from MeV energies up to hundreds of TeV. Similarly, the X-ray sky has been and continues to be monitored by decade-old observatories. Upcoming telescopes will further bolster searches and allow new discovery space for lines from, e.g., sterile neutrinos and axion-photon conversion.
Furthermore, this overview discusses currently operating cosmic-ray probes and the landscape of future experiments that will clarify existing persistent anomalies in cosmic radiation and spearhead possible new discoveries.
Finally, the article closes with a discussion of necessary cross section measurements that need to be conducted at colliders to reduce substantial uncertainties in interpreting photon and cosmic-ray measurements in space.

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T. Aramaki, M. Boezio, J. Buckley, et. al.
Tue, 15 Mar 22
67/108

Comments: 59 pages, 20 figures, Snowmass2021 Cosmic Frontier White Paper

Snowmass2021 Cosmic Frontier White Paper: Puzzling Excesses in Dark Matter Searches and How to Resolve Them [CL]

http://arxiv.org/abs/2203.06859


Intriguing signals with excesses over expected backgrounds have been observed in many astrophysical and terrestrial settings, which could potentially have a dark matter origin. Astrophysical excesses include the Galactic Center GeV gamma-ray excess detected by the Fermi Gamma-Ray Space Telescope, the AMS antiproton and positron excesses, and the 511 and 3.5 keV X-ray lines. Direct detection excesses include the DAMA/LIBRA annual modulation signal, the XENON1T excess, and low-threshold excesses in solid state detectors. We discuss avenues to resolve these excesses, with actions the field can take over the next several years.

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R. Leane, S. Shin, L. Yang, et. al.
Tue, 15 Mar 22
72/108

Comments: 57 pages, solicited white paper submitted to the Proceedings of the US Community Study on the Future of Particle Physics (Snowmass 2021)

Coherent elastic neutrino-nucleus scattering: Terrestrial and astrophysical applications [CL]

http://arxiv.org/abs/2203.07361


Coherent elastic neutrino-nucleus scattering (CE$\nu$NS) is a process in which neutrinos scatter on a nucleus which acts as a single particle. Though the total cross section is large by neutrino standards, CE$\nu$NS has long proven difficult to detect, since the deposited energy into the nucleus is $\sim$ keV. In 2017, the COHERENT collaboration announced the detection of CE$\nu$NS using a stopped-pion source with CsI detectors, followed up the detection of CE$\nu$NS using an Ar target. The detection of CE$\nu$NS has spawned a flurry of activities in high-energy physics, inspiring new constraints on beyond the Standard Model (BSM) physics, and new experimental methods. The CE$\nu$NS process has important implications for not only high-energy physics, but also astrophysics, nuclear physics, and beyond. This whitepaper discusses the scientific importance of CE$\nu$NS, highlighting how present experiments such as COHERENT are informing theory, and also how future experiments will provide a wealth of information across the aforementioned fields of physics.

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M. Abdullah, H. Abele, D. Akimov, et. al.
Tue, 15 Mar 22
73/108

Comments: contribution to Snowmasss 2021. Contact authors: P. S. Barbeau, R. Strauss, L. E. Strigari

New Constraints on Exotic Spin-Velocity-Dependent Interactions [CL]

http://arxiv.org/abs/2203.07050


Experimental searches for new, “fifth” forces are attracting a lot of attention because they allow to test theoretical extensions to the standard model. Here, we report a new experimental search for possible fifth forces, specifically spin-and-velocity dependent forces, by using a K-Rb-$^{21}$Ne co-magnetometer and a tungsten ring featuring a high nucleon density. Taking advantage of the high sensitivity of the co-magnetometer, the pseudomagnetic field from the fifth force is measured to be $<7$\,aT. This sets new limits on coupling constants for the neutron-nucleon and proton-nucleon interactions in the range of $\ge 0.1$ m. The coupling constant limits are established to be $|g_V^n|<6.6\times 10^{-11}$ and $|g_V^p|<3.0\times 10^{-10}$, which are more than one order of magnitude tighter than astronomical and cosmological limits on the coupling between the new gauge boson such as Z$’$ and standard model particles.

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K. Wei, W. Ji, C. Fu, et. al.
Tue, 15 Mar 22
81/108

Comments: N/A

Snowmass 2021 Cosmic Frontier White Paper: Cosmology with Millimeter-Wave Line Intensity Mapping [CEA]

http://arxiv.org/abs/2203.07258


Next-generation tests of fundamental physics and cosmology using large scale structure require measurements over large volumes of the Universe, including high redshifts inaccessible to present-day surveys. Line intensity mapping, an emerging technique that detects the integrated emission of atomic and molecular lines without resolving sources, can efficiently map cosmic structure over a wide range of redshifts. Observations at millimeter wavelengths detect far-IR emission lines such as CO/[CII], and take advantage of observational and analysis techniques developed by CMB experiments. These measurements can provide constraints with unprecedented precision on the physics of inflation, neutrino masses, light relativistic species, dark energy and modified gravity, and dark matter, among many other science goals. In this white paper we forecast the sensitivity requirements for future ground-based mm-wave intensity mapping experiments to enable transformational cosmological constraints. We outline a staged experimental program to steadily improve sensitivity, and describe the necessary investments in developing detector technology and analysis techniques.

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K. Karkare, A. Dizgah, G. Keating, et. al.
Tue, 15 Mar 22
82/108

Comments: 25 pages, 4 figures. Contribution to Snowmass 2021

Snowmass2021 Cosmic Frontier White Paper: Ultraheavy particle dark matter [CL]

http://arxiv.org/abs/2203.06508


We outline the unique opportunities and challenges in the search for “ultraheavy” dark matter candidates with masses between roughly $10~{\rm TeV}$ and the Planck scale $m_{\rm pl} \approx 10^{16}~{\rm TeV}$. This mass range presents a wide and relatively unexplored dark matter parameter space, with a rich space of possible models and cosmic histories. We emphasize that both current detectors and new, targeted search techniques, via both direct and indirect detection, are poised to contribute to searches for ultraheavy particle dark matter in the coming decade. We highlight the need for new developments in this space, including new analyses of current and imminent direct and indirect experiments targeting ultraheavy dark matter and development of new, ultra-sensitive detector technologies like next-generation liquid noble detectors, neutrino experiments, and specialized quantum sensing techniques.

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D. Carney, N. Raj, Y. Bai, et. al.
Tue, 15 Mar 22
85/108

Comments: Solicited community whitepaper for the Snowmass2021 process (Cosmic frontier, particle dark matter working group). 10 pages, 3 figures, many references. Comments welcome

Snowmass2021: Opportunities from Cross-survey Analyses of Static Probes [CL]

http://arxiv.org/abs/2203.06795


Cosmological data in the next decade will be characterized by high-precision, multi-wavelength measurements of thousands of square degrees of the same patches of sky. By performing multi-survey analyses that harness the correlated nature of these datasets, we will gain access to new science, and increase the precision and robustness of science being pursued by each individual survey. However, effective application of such analyses requires a qualitatively new level of investment in cross-survey infrastructure, including simulations, associated modeling, coordination of data sharing, and survey strategy. The scientific gains from this new level of investment are multiplicative, as the benefits can be reaped by even present-day instruments, and can be applied to new instruments as they come online.

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E. Baxter, C. Chang, A. Hearin, et. al.
Tue, 15 Mar 22
89/108

Comments: Contribution to Snowmass 2021

Directional Detection of Dark Matter Using Solid-State Quantum Sensing [CL]

http://arxiv.org/abs/2203.06037


Next-generation dark matter (DM) detectors searching for weakly interacting massive particles (WIMPs) will be sensitive to coherent scattering from solar neutrinos, demanding an efficient background-signal discrimination tool. Directional detectors improve sensitivity to WIMP DM despite the irreducible neutrino background. Wide-bandgap semiconductors offer a path to directional detection in a high-density target material. A detector of this type operates in a hybrid mode. The WIMP or neutrino-induced nuclear recoil is detected using real-time charge, phonon, or photon collection. The directional signal, however, is imprinted as a durable sub-micron damage track in the lattice structure. This directional signal can be read out by a variety of atomic physics techniques, from point defect quantum sensing to x-ray microscopy. In this white paper, we present the detector principle and review the status of the experimental techniques required for directional readout of nuclear recoil tracks. Specifically, we focus on diamond as a target material; it is both a leading platform for emerging quantum technologies and a promising component of next-generation semiconductor electronics. Based on the development and demonstration of directional readout in diamond over the next decade, a future WIMP detector will leverage or motivate advances in multiple disciplines towards precision dark matter and neutrino physics.

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R. Ebadi, M. Marshall, D. Phillips, et. al.
Mon, 14 Mar 22
2/67

Comments: contribution to Snowmass 2021, 28 pages + references, 14 figures

The Forward Physics Facility at the High-Luminosity LHC [CL]

http://arxiv.org/abs/2203.05090


High energy collisions at the High-Luminosity Large Hadron Collider (LHC) produce a large number of particles along the beam collision axis, outside of the acceptance of existing LHC experiments. The proposed Forward Physics Facility (FPF), to be located several hundred meters from the ATLAS interaction point and shielded by concrete and rock, will host a suite of experiments to probe Standard Model (SM) processes and search for physics beyond the Standard Model (BSM). In this report, we review the status of the civil engineering plans and the experiments to explore the diverse physics signals that can be uniquely probed in the forward region. FPF experiments will be sensitive to a broad range of BSM physics through searches for new particle scattering or decay signatures and deviations from SM expectations in high statistics analyses with TeV neutrinos in this low-background environment. High statistics neutrino detection will also provide valuable data for fundamental topics in perturbative and non-perturbative QCD and in weak interactions. Experiments at the FPF will enable synergies between forward particle production at the LHC and astroparticle physics to be exploited. We report here on these physics topics, on infrastructure, detector, and simulation studies, and on future directions to realize the FPF’s physics potential.

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J. Feng, F. Kling, M. Reno, et. al.
Mon, 14 Mar 22
4/67

Comments: 429 pages, contribution to Snowmass 2021

Inter-Calibration of Atmospheric Cherenkov Telescopes with UAV-based Airborne Calibration System [IMA]

http://arxiv.org/abs/2203.05839


The recent advances in the flight capability of remotely piloted aerial vehicles (here after referred to as UAVs) have afforded the astronomical community the possibility of a new telescope calibration technique: UAV-based calibration. Building upon a feasibility study which characterised the potential that a UAV-based calibration system has for the future Cherenkov Telescope Array, we created a first-generation UAV-calibration prototype and undertook a field-campaign of inter-calibrating the sensitivity of the H.E.S.S. telescope array with two successful calibration flights. In this paper we report the key results of our first test campaign: firstly, by comparing the intensity of the UAV-calibration events, as recorded by the individual HESS-I cameras, we find that a UAV-based inter-calibration is consistent with the standard muon inter-calibration technique at the level of \SI{5.4}{\%} and \SI{5.8}{\%} for the two individual UAV-calibration runs. Secondly, by comparing the position of the UAV-calibration signal on the camera focal plane, for a variety of telescope pointing models, we were able to constrain the pointing accuracy of the HESS-I telescopes at the tens of arc-second accuracy level. This is consistent with the pointing accuracy derived from other pointing calibration methods. Importantly both the inter-calibration and pointing accuracy results were achieved with a first-generation UAV-calibration prototype, which eludes to the potential of the technique and highlights that a UAV-based system is a viable calibration technique for current and future ground-based $\gamma$-ray telescope arrays.

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A. Brown, J. Muller, M. Naurois, et. al.
Mon, 14 Mar 22
25/67

Comments: 30 pages, accepted for publication in Astroparticle Physics

Recoil imaging for dark matter, neutrinos, and physics beyond the Standard Model [CL]

http://arxiv.org/abs/2203.05914


Recoil imaging entails the detection of spatially resolved ionization tracks generated by particle interactions. This is a highly sought-after capability in many classes of detector, with broad applications across particle and astroparticle physics. However, at low energies, where ionization signatures are small in size, recoil imaging only seems to be a practical goal for micro-pattern gas detectors. This white paper outlines the physics case for recoil imaging, and puts forward a decadal plan to advance towards the directional detection of low-energy recoils with sensitivity and resolution close to fundamental performance limits. The science case covered includes: the discovery of dark matter into the neutrino fog, directional detection of sub-MeV solar neutrinos, the precision study of coherent-elastic neutrino-nucleus scattering, the detection of solar axions, the measurement of the Migdal effect, X-ray polarimetry, and several other applied physics goals. We also outline the R\&D programs necessary to test concepts that are crucial to advance detector performance towards their fundamental limit: single primary electron sensitivity with full 3D spatial resolution at the $\sim$100 micron-scale. These advancements include: the use of negative ion drift, electron counting with high-definition electronic readout, time projection chambers with optical readout, and the possibility for nuclear recoil tracking in high-density gases such as argon. We also discuss the readout and electronics systems needed to scale-up such detectors to the ton-scale and beyond.

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C. O’Hare, D. Loomba, K. Altenmüller, et. al.
Mon, 14 Mar 22
29/67

Comments: 77 pages, 20 figures. Submitted to the Proceedings of the US Community Study on the Future of Particle Physics (Snowmass 2021)

Symmetry Group Equivariant Architectures for Physics [CL]

http://arxiv.org/abs/2203.06153


Physical theories grounded in mathematical symmetries are an essential component of our understanding of a wide range of properties of the universe. Similarly, in the domain of machine learning, an awareness of symmetries such as rotation or permutation invariance has driven impressive performance breakthroughs in computer vision, natural language processing, and other important applications. In this report, we argue that both the physics community and the broader machine learning community have much to understand and potentially to gain from a deeper investment in research concerning symmetry group equivariant machine learning architectures. For some applications, the introduction of symmetries into the fundamental structural design can yield models that are more economical (i.e. contain fewer, but more expressive, learned parameters), interpretable (i.e. more explainable or directly mappable to physical quantities), and/or trainable (i.e. more efficient in both data and computational requirements). We discuss various figures of merit for evaluating these models as well as some potential benefits and limitations of these methods for a variety of physics applications. Research and investment into these approaches will lay the foundation for future architectures that are potentially more robust under new computational paradigms and will provide a richer description of the physical systems to which they are applied.

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A. Bogatskiy, S. Ganguly, T. Kipf, et. al.
Mon, 14 Mar 22
31/67

Comments: Contribution to Snowmass 2021

Tau Neutrinos in the Next Decade: from GeV to EeV [CL]

http://arxiv.org/abs/2203.05591


Tau neutrinos are the least studied particle in the Standard Model. This whitepaper discusses the current and expected upcoming status of tau neutrino physics with attention to the broad experimental and theoretical landscape spanning long-baseline, beam-dump, collider, and astrophysical experiments. This whitepaper was prepared as a part of the NuTau2021 Workshop.

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R. Abraham, J. Alvarez-Muñiz, C. Argüelles, et. al.
Mon, 14 Mar 22
34/67

Comments: 154 pages, 63 figures, 10 tables, 68 endorsers, comments welcome~ Contribution to Snowmass 2021

Incident Velocity-Recoil Angle Distribution and Angular Recoil-Energy Spectrum of 3-Dimensional WIMP-Nucleus Scattering Events [CL]

http://arxiv.org/abs/2203.05805


In this paper, as a supplementary of our study on the angular distribution of the recoil flux of WIMP-scattered target nuclei and on that of the WIMP effective scattering velocity distribution, we investigate the scattering probability distribution of the WIMP incident velocity versus the nuclear recoil angle in narrow recoil energy windows for different WIMP masses and target nuclei. Our simulation results show that, not only the velocity distribution of incident halo WIMPs, but also a factor of the recoil angle could affect the scattering probability distribution of the available incident velocity-recoil angle combination in a given recoil energy window. Consequently, the 1-D WIMP “effective” velocity distribution corresponding to the considered narrow energy window would not be consistent with that cut simply from the (generating) velocity distribution of incident halo WIMPs. And its contribution to the differential WIMP-nucleus scattering event rate in the considered energy window could thus not be simply estimated by integrating over the 1-D theoretical velocity distribution (of entire halo WIMPs).

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C. Shan
Mon, 14 Mar 22
35/67

Comments: 14 pages, 6 figures. For readers’ reference, simulation results for several frequently used target nuclei are demonstrated in animation on and downloadable from our online (interactive) webpage (this http URL)

Snowmass2021 CMB-HD White Paper [CEA]

http://arxiv.org/abs/2203.05728


CMB-HD is a proposed millimeter-wave survey over half the sky that would be ultra-deep (0.5 uK-arcmin) and have unprecedented resolution (15 arcseconds at 150 GHz). Such a survey would answer many outstanding questions about the fundamental physics of the Universe. Major advances would be 1.) the use of gravitational lensing of the primordial microwave background to map the distribution of matter on small scales (k~10 h Mpc^(-1)), which probes dark matter particle properties. It will also allow 2.) measurements of the thermal and kinetic Sunyaev-Zel’dovich effects on small scales to map the gas density and velocity, another probe of cosmic structure. In addition, CMB-HD would allow us to cross critical thresholds: 3.) ruling out or detecting any new, light (< 0.1 eV) particles that were in thermal equilibrium with known particles in the early Universe, 4.) testing a wide class of multi-field models that could explain an epoch of inflation in the early Universe, and 5.) ruling out or detecting inflationary magnetic fields. CMB-HD would also provide world-leading constraints on 6.) axion-like particles, 7.) cosmic birefringence, 8.) the sum of the neutrino masses, and 9.) the dark energy equation of state. The CMB-HD survey would be delivered in 7.5 years of observing 20,000 square degrees of sky, using two new 30-meter-class off-axis crossed Dragone telescopes to be located at Cerro Toco in the Atacama Desert. Each telescope would field 800,000 detectors (200,000 pixels), for a total of 1.6 million detectors.

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C. Collaboration, S. Aiola, Y. Akrami, et. al.
Mon, 14 Mar 22
40/67

Comments: Contribution to Snowmass 2021. Note some text overlap with CMB-HD Astro2020 APC and RFI (1906.10134, 2002.12714). Science case further broadened and updated

New Ideas in Baryogenesis: A Snowmass White Paper [CL]

http://arxiv.org/abs/2203.05010


The Standard Model of Particle Physics cannot explain the observed baryon asymmetry of the Universe. This observation is a clear sign of new physics beyond the Standard Model. There have been many recent theoretical developments to address this question. Critically, many new physics models that generate the baryon asymmetry have a wide range of repercussions for many areas of theoretical and experimental particle physics. This white paper provides an overview of such recent theoretical developments with an emphasis on experimental testability.

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G. Elor, J. Harz, S. Ipek, et. al.
Fri, 11 Mar 22
38/59

Comments: Contribution to Snowmass 2021. Solicited white paper from TF08

A parametric approach for the identification of single-charged isotopes with AMS-02 [HEAP]

http://arxiv.org/abs/2203.04025


Measurements of the isotopic composition of single-charged cosmic rays provide important insights in the propagation processes. However, the isotopic identification is challenging due to the one hundred times greater abundance of protons when compared to deuterons, the only stable isotope of hydrogen. Taking advantage of the precise measurements of the velocity and momentum in the Alpha Magnetic Spectrometer (AMS-02), a particle physics detector operating aboard the International Space Station since May 2011, we describe a parametric template fit method, which takes into account systematic uncertainties such as the fragmentation of particles inside AMS-02 and eventual differences between data and simulation through the use of nuisance parameters. With this method we are also able to assess the AMS-02 performance in terms of mass resolution, showing that it is able to separate the isotopes of hydrogen up to 10 GeV/n.

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E. Bueno, F. Barão and M. Vecchi
Wed, 9 Mar 22
42/68

Comments: Accepted for publication in Nuclear Instruments and Methods in Physics Research Section A

On the equivalence between rotation and gravity: "Gravitational" and "cosmological" redshifts in the laboratory [CL]

http://arxiv.org/abs/2203.02282


The M\”ossbauer rotor effect recently gained a renewed interest due to the discovery and explanation of an additional effect of clock synchronization which has been missed for about 50 years, i.e. starting from a famous book of Pauli, till some recent experimental analyses. The theoretical explanation of such an additional effect is due to some recent papers in both the general relativistic and the special relativistic frameworks. In the first case (general relativistic framework) the key point of the approach is the Einstein’s equivalence principle (EEP), which, in the words of the same Einstein, enables “the point of view to interpret the rotating system K’ as at rest, and the centrifugal field as a gravitational field”. In this paper, we analyse both the history of the M\”ossbauer rotor effect and its interpretation from the point of view of Einstein’s general theory of relativity (GTR) by adding some new insight. In particular, it will be shown that, if on one hand the “traditional” effect of redshift has a strong analogy with the gravitational redshift, on the other hand the additional effect of clock synchronization has an intriguing analogy with the cosmological redshift. Finally, we show that a recent claim in the literature that the second effect of clock synchronization does not exist is not correct.

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C. Corda
Mon, 7 Mar 22
18/64

Comments: 17 pages, 1 figure, accepted for publication in Foundations of Physics. Comments are welcome

Low Energy Event Reconstruction in IceCube DeepCore [CL]

http://arxiv.org/abs/2203.02303


The reconstruction of event-level information, such as the direction or energy of a neutrino interacting in IceCube DeepCore, is a crucial ingredient to many physics analyses. Algorithms to extract this high level information from the detector’s raw data have been successfully developed and used for high energy events. In this work, we address unique challenges associated with the reconstruction of lower energy events in the range of a few to hundreds of GeV and present two separate, state-of-the-art algorithms. One algorithm focuses on the fast directional reconstruction of events based on unscattered light. The second algorithm is a likelihood-based multipurpose reconstruction offering superior resolutions, at the expense of larger computational cost.

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R. Abbasi, M. Ackermann, J. Adams, et. al.
Mon, 7 Mar 22
19/64

Comments: N/A

A Next-Generation Liquid Xenon Observatory for Dark Matter and Neutrino Physics [CL]

http://arxiv.org/abs/2203.02309


The nature of dark matter and properties of neutrinos are among the most pressing issues in contemporary particle physics. The dual-phase xenon time-projection chamber is the leading technology to cover the available parameter space for Weakly Interacting Massive Particles (WIMPs), while featuring extensive sensitivity to many alternative dark matter candidates. These detectors can also study neutrinos through neutrinoless double-beta decay and through a variety of astrophysical sources. A next-generation xenon-based detector will therefore be a true multi-purpose observatory to significantly advance particle physics, nuclear physics, astrophysics, solar physics, and cosmology. This review article presents the science cases for such a detector.

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J. Aalbers, K. Abe, V. Aerne, et. al.
Mon, 7 Mar 22
37/64

Comments: 77 pages, 40 figures, 1262 references

Optimization study of the electrode design of a 5 mm thick orthogonal-strip CdZnTe detector system [CL]

http://arxiv.org/abs/2203.02332


The geometry of electrodes is one of the most important factors in determining the performance of orthogonal-strip detectors. The aim of this work is to study the performance of a 5 mm thick cross-strip CdZnTe detector with different electrode widths. Our study consists of two main parts, simulations and experiments. We utilized four different anode sizes ranging from 0.1 mm to 0.6 mm. The anodes were interspersed with steering electrodes with varying sizes from 0.3 mm to 0.85 mm. The maximum gap size between the anodes and steering electrode strips was set to 0.3 mm, while the minimum gap size was 0.125 mm. The performance of the detector was investigated in terms of the steering electrode bias voltage, the energy resolution, and the charge sharing effect. For simulations, we developed a C++ based simulation program for charge transport inside the CdZnTe detector and charge collection at the electrodes. For photon interactions we used GEANT4 toolkit and for electric field and weighting potential simulations we used COMSOL software. The results demonstrated that -50 V is the optimal steering electrode bias for our detector when -500 V was applied to the cathodes and that the energy resolution performance drops with increasing steering electrode width. Also, the charge sharing effect becomes more dominant for larger steering electrode sizes. The experimental result are further compared with the simulations. The results are in a good agreement and the comparison validates our simulation model. Although, our simulation framework has need of better estimation for the intrinsic noise of CdZnTe. These results suggest that an optimization study between electrode widths and steering electrode bias is required to obtain the best performance in orthogonal-strip CdZnTe detectors.

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A. Altingun and E. Kalemci
Mon, 7 Mar 22
39/64

Comments: N/A

Neutrino Self-Interactions: A White Paper [CL]

http://arxiv.org/abs/2203.01955


Neutrinos are the Standard Model (SM) particles which we understand the least, often due to how weakly they interact with the other SM particles. Beyond this, very little is known about interactions among the neutrinos, i.e., their self-interactions. The SM predicts neutrino self-interactions at a level beyond any current experimental capabilities, leaving open the possibility for beyond-the-SM interactions across many energy scales. In this white paper, we review the current knowledge of neutrino self-interactions from a vast array of probes, from cosmology, to astrophysics, to the laboratory. We also discuss theoretical motivations for such self-interactions, including neutrino masses and possible connections to dark matter. Looking forward, we discuss the capabilities of searches in the next generation and beyond, highlighting the possibility of future discovery of this beyond-the-SM physics.

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J. Berryman, N. Blinov, V. Brdar, et. al.
Mon, 7 Mar 22
46/64

Comments: Editors: Nikita Blinov, Mauricio Bustamante, Kevin J. Kelly, Yue Zhang. 29 pages, 16 figures, plus references. Contribution to Snowmass 2021

Exploiting a future galactic supernova to probe neutrino magnetic moments [CL]

http://arxiv.org/abs/2203.01950


A core-collapse supernova (SN) offers an excellent astrophysical laboratory to test non-zero neutrino magnetic moments. In particular, the neutronization burst phase, which lasts for few tens of milliseconds post-bounce, is dominated by electron neutrinos and can offer exceptional discovery potential for transition magnetic moments. We simulate the neutrino spectra from the burst phase in forthcoming neutrino experiments like the Deep Underground Neutrino Experiment (DUNE), and the Hyper-Kamiokande (HK), by taking into account spin-flavour conversions of SN neutrinos, caused by interactions with ambient magnetic fields. We find that the neutrino transition magnetic moments which can be explored by these experiments for a galactic SN are an order to several orders of magnitude better than the current terrestrial and astrophysical limits. Additionally, we also discuss how this realization might shed light on three important neutrino properties: (a) the Dirac/Majorana nature, (b) the neutrino mass ordering, and (c) the neutrino mass-generation mechanism.

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S. Jana, Y. Porto-Silva and M. Sen
Mon, 7 Mar 22
58/64

Comments: 30 pages, 9 figures, comments welcome

Novel electron and photon recording concepts in noble-liquid detectors [CL]

http://arxiv.org/abs/2203.01774


We present several novel ionization-electron and scintillation-photon recording concepts in noble-liquid detectors, for future applications in particle and astroparticle physics and in other fields. These involve both single- and dual-phase detector configurations with combined electroluminescence and small charge multiplication in gas and liquid media.

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A. Breskin
Fri, 4 Mar 22
47/63

Comments: 32 pages, 15 figures, to be submitted to JINST

Theia: Summary of physics program. Snowmass White Paper Submission [CL]

http://arxiv.org/abs/2202.12839


Theia would be a novel, “hybrid” optical neutrino detector, with a rich physics program. This paper is intended to provide a brief overview of the concepts and physics reach of Theia. Full details can be found in the Theia white paper [1].

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M. Askins, Z. Bagdasarian, N. Barros, et. al.
Mon, 28 Feb 22
12/38

Comments: Contribution to Snowmass 2021

History of Solar Neutrino Observations [CL]

http://arxiv.org/abs/2202.12421


The first solar neutrino experiment led by Raymond Davis Jr. showed a deficit of neutrinos relative to the solar model prediction, referred to as the “solar neutrino problem” since the 1970s. The Kamiokande experiment led by Masatoshi Koshiba successfully observed solar neutrinos, as first reported in 1989. The observed flux of solar neutrinos was almost half the prediction and confirmed the solar neutrino problem. This problem was not resolved for some time due to possible uncertainties in the solar model. In 2001, it was discovered that the solar neutrino problem is due to neutrino oscillations by comparing the Super-Kamiokande and Sudbury Neutrino Observatory results, which was the first model-independent comparison. Detailed studies of solar neutrino oscillations have since been performed, and the results of solar neutrino experiments are consistent with solar model predictions when the effect of neutrino oscillations are taken into account. In this article, the history of solar neutrino observations is reviewed with the contributions of Kamiokande and Super-Kamiokande detailed.

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M. Nakahata
Mon, 28 Feb 22
34/38

Comments: 29 pages, 20 figures, accepted by PTEP as a paper for “A special issue in memory of Masatoshi Koshiba, a pioneer in experimental particle physics and astrophysics”

Measurement of Energy Spectrum and Elemental Composition of PeV Cosmic Rays: Open Problems and Prospects [HEAP]

http://arxiv.org/abs/2202.11618


Cosmic rays represent one of the most important energy transformation processes of the universe. They bring information about the surrounding universe, our galaxy, and very probably also the extragalactic space, at least at the highest observed energies. More than one century after their discovery, we have no definitive models yet about the origin, acceleration and propagation processes of the radiation. The main reason is that there are still significant discrepancies among the results obtained by different experiments located at ground level, probably due to unknown systematic uncertainties affecting the measurements. In this document, we will focus on the detection of galactic cosmic rays from ground with air shower arrays up to 10$^{18}$ eV. The aim of this paper is to discuss the conflicting results in the 10$^{15}$ eV energy range and the perspectives to clarify the origin of the so-called `knee’ in the all-particle energy spectrum, crucial to give a solid basis for models up to the end of the cosmic ray spectrum. We will provide elements useful to understand the basic techniques used in reconstructing primary particle characteristics (energy, mass, and arrival direction) from the ground, and to show why indirect measurements are difficult and results are still conflicting.

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G. Sciascio
Thu, 24 Feb 22
45/52

Comments: Invited Review, Special Issue “Research on Cosmic Rays and Their Impact on Human Activities”, Applied Sciences (2022) 12(2):705. this https URL

Probing Neutrino Mass Models through Resonances at Neutrino Telescopes [CL]

http://arxiv.org/abs/2202.06975


We study the detection prospects of relatively light charged scalars in radiative Majorana neutrino mass models, such as the Zee model and its variants using scalar leptoquarks, at current and future neutrino telescopes. In particular, we show that these scalar mediators can give rise to Glashow-like resonance features in the ultra-high energy neutrino (UHE) event spectrum at the IceCube neutrino observatory and its high-energy upgrade IceCube-Gen2. The same scalars can also give rise to observable non-standard neutrino interactions (NSI), and we show that the UHE neutrinos provide a complementary probe of NSI. We also discuss an interesting possibility of producing such resonances by incoming sterile neutrino components in the case where neutrinos are pseudo-Dirac particles.

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K. Babu, P. Dev and S. Jana
Wed, 16 Feb 22
38/69

Comments: 22 pages + references, 8 figures, invited review for International Journal of Modern Physics A, contains several new results, comments welcome

SUPA: A Lightweight Diagnostic Simulator for Machine Learning in Particle Physics [CL]

http://arxiv.org/abs/2202.05012


Deep learning methods have gained popularity in high energy physics for fast modeling of particle showers in detectors. Detailed simulation frameworks such as the gold standard Geant4 are computationally intensive, and current deep generative architectures work on discretized, lower resolution versions of the detailed simulation. The development of models that work at higher spatial resolutions is currently hindered by the complexity of the full simulation data, and by the lack of simpler, more interpretable benchmarks. Our contribution is SUPA, the SUrrogate PArticle propagation simulator, an algorithm and software package for generating data by simulating simplified particle propagation, scattering and shower development in matter. The generation is extremely fast and easy to use compared to Geant4, but still exhibits the key characteristics and challenges of the detailed simulation. We support this claim experimentally by showing that performance of generative models on data from our simulator reflects the performance on a dataset generated with Geant4. The proposed simulator generates thousands of particle showers per second on a desktop machine, a speed up of up to 6 orders of magnitudes over Geant4, and stores detailed geometric information about the shower propagation. SUPA provides much greater flexibility for setting initial conditions and defining multiple benchmarks for the development of models. Moreover, interpreting particle showers as point clouds creates a connection to geometric machine learning and provides challenging and fundamentally new datasets for the field.
The code for SUPA is available at https://github.com/itsdaniele/SUPA.

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A. Sinha, D. Paliotta, B. Máté, et. al.
Fri, 11 Feb 22
61/71

Comments: N/A

New Constraint on the Local Relic Neutrino Background Overdensity with the First KATRIN Data Runs [CL]

http://arxiv.org/abs/2202.04587


We report on the direct cosmic relic neutrino background search from the first two science runs of the KATRIN experiment in 2019. Beta-decay electrons from a high-purity molecular tritium gas source are analyzed by a high-resolution MAC-E filter around the kinematic endpoint at 18.57 keV. The analysis is sensitive to a local relic neutrino overdensity of 9.7e10 (1.1e11) at a 90% (95%) confidence level. A fit of the integrated electron spectrum over a narrow interval around the kinematic endpoint accounting for relic neutrino captures in the Tritium source reveals no significant overdensity. This work improves the results obtained by the previous kinematic neutrino mass experiments at Los Alamos and Troitsk. We furthermore update the projected final sensitivity of the KATRIN experiment to <1e10 at 90% confidence level, by relying on updated operational conditions.

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M. Aker, D. Batzler, A. Beglarian, et. al.
Thu, 10 Feb 22
37/66

Comments: 7 pages, 7 figures

PKS 1424+240: yet another masquerading BL Lac object as a possible IceCube neutrino source [HEAP]

http://arxiv.org/abs/2202.04363


We show that the blazar PKS 1424+240, which has been recently associated by IceCube with a neutrino excess at the $3.3\,\sigma$ level together with three other sources, is similar to the first plausible non-stellar neutrino source, TXS 0506+056, in being also a masquerading BL Lac object, i.e., intrinsically a flat-spectrum radio quasar with hidden broad lines and a standard accretion disk. We point out that these two sources share other properties, including spectral energy distribution, high powers, parsec scale properties, and possibly radio morphology. We speculate that the relatively rare combination of proton-loaded jets, possibly typical of high-excitation sources, and efficient particle acceleration processes, related to their relatively high synchrotron peak frequencies, might favour neutrino production in these two sources. GB6 J1542+6129, which has also recently appeared twice in a list of IceCube associations, seems also to belong to this rare blazar sub-class, which includes at most ~ 20 Fermi-4LAC blazars.

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P. Padovani, B. Boccardi, R. Falomo, et. al.
Thu, 10 Feb 22
44/66

Comments: 5 pages, 3 figures, accepted for publication in MNRAS

Constraints on the electron-hole pair creation energy and Fano factor below 150 eV from Compton scattering in a Skipper-CCD [CL]

http://arxiv.org/abs/2202.03924


Fully-depleted thick silicon Skipper-charge-coupled devices (Skipper-CCDs) have achieved sub-electron read-out noise and are an important technology to probe neutrino and light dark matter interactions. However, the successful search for rare neutrino or dark-matter events requires the signal and all backgrounds to be fully characterized. In particular, a measurement of the electron-hole pair creation energy below 150\,eV and the Fano factor are necessary for characterizing the dark matter and neutrino signals. Moreover, photons from background radiation may Compton scatter in the silicon bulk, producing events that can mimic a dark matter or neutrino signal. We present a measurement of the Compton spectrum using a Skipper-CCD and a $^{241}$Am source. With these data, we measure the electron-hole pair-creation energy to be $\left(3.71 \pm 0.08\right)$\,eV at 130\,K in the energy range between 99.3 eV and 150 eV. By measuring the widths of the steps at 99.3 eV and 150 eV in the Compton spectrum, we introduce a novel technique to measure the Fano factor, setting an upper limit of 0.31 at 90\% C.L. These results prove the potential of Skipper-CCDs to characterize the Compton spectrum and to measure precisely the Fano factor and electron-hole pair creation energy below 150\,eV.

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A. Botti, S. Uemura, G. Moroni, et. al.
Wed, 9 Feb 22
30/48

Comments: N/A

Revisiting the Dark Matter Interpretation of Excess Rates in Semiconductors [CL]

http://arxiv.org/abs/2202.03436


In light of recent results from low-threshold dark matter detectors, we revisit the possibility of a common dark matter origin for multiple excesses across numerous direct detection experiments, with a focus on the excess rates in semiconductor detectors. We explore the interpretation of the low-threshold calorimetric excess rates above 40 eV in the silicon SuperCDMS Cryogenic Phonon Detector and above 100 eV in the germanium EDELWEISS Surface detector as arising from a common but unknown origin, and demonstrate a compatible fit for the observed energy spectra in both experiments, which follow a power law of index $\alpha = 3.43^{+0.11}_{-0.06}$. Despite the intriguing scaling of the normalization of these two excess rates with approximately the square of the mass number $A^2$, we argue that the possibility of common origin by dark matter scattering via nuclear recoils is strongly disfavored, even allowing for exotic condensed matter effects in an as-yet unmeasured kinematic regime. We also investigate the possibility of inelastic nuclear scattering by cosmic ray neutrons, solar neutrinos, and photons as the origin, and quantitatively disfavor all three based on known fluxes of particles.

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P. Abbamonte, D. Baxter, Y. Kahn, et. al.
Wed, 9 Feb 22
38/48

Comments: 9 pages, 3 figures

Measurement of atmospheric muon angular distribution using a portable setup of liquid scintillator bars [CL]

http://arxiv.org/abs/2202.01445


Measurements of cosmogenic particles at various locations and altitudes are becoming increasingly important in view of worldwide interests in rare signals for search of new physics. In this work, we report measurement of muon zenith angle distributions and integrated flux using a portable setup of four one-meter long liquid scintillator bars. Each scintillator bar is read out from both sides via photomultiplier tubes followed by an 8-channel Digitizer. We exploit energy deposition and excellent timing of scintillators to construct two dimensional tracks and hence angles of charged particles. We use liquid scintillators since they have an added advantage of pulse shape discrimination (PSD) which can be used for detecting muon induced particles. The energy deposition, time window of event and PSD cuts are used to reduce the random as well as correlated backgrounds. In addition, we propose three track quality parameters which are applied to obtain a clean muon spectrum. The zenith angle measurement is performed upto $60^\circ$. With our improved analysis, we demonstrate that a setup of 3 bars can also be used for quicker and precise measurements. The vertical muon flux measured is $66.70 \pm 0.36 \pm 1.50$ with $n=2.10 \pm 0.05 \pm 0.25 $ in $\cos^n \theta$ at the location of Mumbai, India ($19^{\circ}$N, $72.9^{\circ}$E) at Sea level with a muon momentum above $255$ GeV/$c$. The muon flux has dependence on various factors, the most prominents are latitudes, altitudes and momentum cut of muon so that portable setup like this can be a boon for such measurements at various locations.

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H. Sogarwal and P. Shukla
Fri, 4 Feb 22
6/65

Comments: 29 pages, 24 figures

A novel search for high-frequency gravitational waves with low-mass axion haloscopes [CL]

http://arxiv.org/abs/2202.00695


Gravitational waves (GWs) generate oscillating electromagnetic effects in the vicinity of external electric and magnetic fields. We discuss this phenomenon with a particular focus on reinterpreting the results of axion haloscopes based on lumped-element detectors, which probe GWs in the 100 kHz-100 MHz range. Measurements from ABRACADABRA and SHAFT already place bounds on GWs, although the present strain sensitivity is weak. However, we demonstrate that the sensitivity scaling with the volume of such instruments is significant – faster than for axions – and so rapid progress will be made in the future. With no modifications, DMRadio-m$^3$ will have a GW strain sensitivity of $h \sim 10^{-20}$ at 200 MHz. A simple modification of the pickup loop used to readout the induced magnetic flux can parametrically enhance the GW sensitivity, particularly at lower frequencies.

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V. Domcke, C. Garcia-Cely and N. Rodd
Fri, 4 Feb 22
27/65

Comments: 7+9 pages, 3+1 figures, comments welcome

First measurement of the absorption of $^{3}\overline{\rm He}$ nuclei in matter and impact on their propagation in the galaxy [CL]

http://arxiv.org/abs/2202.01549


Antimatter particles such as positrons and antiprotons abound in the cosmos. Much less common are light antinuclei, composed of antiprotons and antineutrons, which can be produced in our galaxy via high-energy cosmic-ray collisions with the interstellar medium or could also originate from the annihilation of the still undiscovered dark-matter particles. On Earth, the only way to produce and study antinuclei with high precision is to create them at high-energy particle accelerators like the Large Hadron Collider (LHC). Though the properties of elementary antiparticles have been studied in detail, knowledge of the interaction of light antinuclei with matter is rather limited. This work focuses on the determination of the disappearance probability of \ahe\ when it encounters matter particles and annihilates or disintegrates. The material of the ALICE detector at the LHC serves as a target to extract the inelastic cross section for \ahe\ in the momentum range of $1.17 \leq p < 10$ GeV/$c$. This inelastic cross section is measured for the first time and is used as an essential input to calculations of the transparency of our galaxy to the propagation of $^{3}\overline{\rm He}$ stemming from dark-matter decays and cosmic-ray interactions within the interstellar medium. A transparency of about 50% is estimated using the GALPROP program for a specific dark-matter profile and a standard set of propagation parameters. For cosmic-ray sources, the obtained transparency with the same propagation scheme varies with increasing $^{3}\overline{\rm He}$ momentum from 25% to 90%. The absolute uncertainties associated to the $^{3}\overline{\rm He}$ inelastic cross section measurements are of the order of 10%$-$15%. The reported results indicate that $^{3}\overline{\rm He}$ nuclei can travel long distances in the galaxy, and can be used to study cosmic-ray interactions and dark-matter decays.

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A. Collaboration
Fri, 4 Feb 22
52/65

Comments: 26 pages, 5 captioned figures, authors from page 21, figures at this http URL

Neutrino Astronomy with IMB, Kamiokande and Super Kamiokande [HEAP]

http://arxiv.org/abs/2202.01676


Some of the earliest work on neutrino astronomy was accomplished by a class of underground detectors primarily designed for particle physics goals . These detectors used inexpensive water to obtain the large masses needed to observe the very low interaction rates expected from neutrinos. They exploited the relatively large light attenuation length and the index of refraction of the water to get a very inexpensive cost per thousand tons of detector.
The results obtained from these pioneering neutrino detectors have included real time observation of solar neutrinos, supernova neutrinos, and atmospheric neutrinos. Searches for neutrino point sources, dark matter and primordial magnetic monopoles were also made using them.

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J. LoSecco
Fri, 4 Feb 22
65/65

Comments: To be published in Neutrino Physics and Astrophysics, edited by F. W. Stecker, in the Encyclopedia of Cosmology II, edited by G. G. Fazio, World Scientific Publishing Company, Singapore, 2022. 41 pages, 31 figures

IceCube and High-Energy Cosmic Neutrinos [HEAP]

http://arxiv.org/abs/2202.00694


The IceCube experiment discovered PeV-energy neutrinos originating beyond our Galaxy with an energy flux that is comparable to that of TeV-energy gamma rays and EeV-energy cosmic rays. Neutrinos provide the only unobstructed view of the cosmic accelerators that power the highest energy radiation reaching us from the universe. We will review the rationale for building kilometer-scale neutrino detectors that led to the IceCube project, which transformed a cubic kilometer of deep transparent natural Antarctic ice into a neutrino telescope of such a scale. We will summarize the results from the first decade of operations: the status of the observations of cosmic neutrinos and of their first identified source, the supermassive black hole TXS 0506+056. Subsequently, we will introduce the phenomenology associated with cosmic accelerators in some detail. Besides the search for the sources of Galactic and extragalactic cosmic rays, the scientific missions of IceCube and similar instruments under construction in the Mediterranean Sea and Lake Baikal include the observation of Galactic supernova explosions, the search for dark matter, and the study of neutrinos themselves. This review resulted from notes created for summer school lectures and should be accessible to nonexperts.

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F. Halzen and A. Kheirandish
Thu, 3 Feb 22
9/56

Comments: To be published in Neutrino Physics and Astrophysics, edited by F. W. Stecker, in the Encyclopedia of Cosmology II, edited by G. G. Fazio, World Scientific Publishing Company, Singapore, 2022

A novel search for high-frequency gravitational waves with low-mass axion haloscopes [CL]

http://arxiv.org/abs/2202.00695


Gravitational waves (GWs) generate oscillating electromagnetic effects in the vicinity of external electric and magnetic fields. We discuss this phenomenon with a particular focus on reinterpreting the results of axion haloscopes based on lumped-element detectors, which probe GWs in the 100 kHz-100 MHz range. Measurements from ABRACADABRA and SHAFT already place bounds on GWs, although the present strain sensitivity is weak. However, we demonstrate that the sensitivity scaling with the volume of such instruments is significant – faster than for axions – and so rapid progress will be made in the future. With no modifications, DMRadio-m$^3$ will have a GW strain sensitivity of $h \sim 10^{-20}$ at 200 MHz. A simple modification of the pickup loop used to readout the induced magnetic flux can parametrically enhance the GW sensitivity, particularly at lower frequencies.

Read this paper on arXiv…

V. Domcke, C. Garcia-Cely and N. Rodd
Thu, 3 Feb 22
48/56

Comments: 7+9 pages, 3+1 figures, comments welcome

Axion cosmology in the presence of non-trivial Nambu-Goldstone modes [CL]

http://arxiv.org/abs/2202.00174


Axion cosmology is reexamined taking into account effect of kinetic pseudo Nambu-Goldstone modes, with its importance recently pointed out. When Peccei-Quinn (PQ) symmetry is broken by a chiral U(1) singlet, it is found the effect of kinetic Nambu-Goldstone mode makes the axion dark matter untenable. When PQ symmetry is extended and is broken by two singlets, we find axion cosmology to work, but there are several differences from the axion cosmology studied in the literature. The differences are (1) ordinary type of dark matter scaling as $1/{\rm cosmic \; scale\; factor}^3$ arising from a modulus field and not from the usual angular field, (2) mass of the dark matter quantum in the ultralight range, $(10^{-32} \sim 10^{-14})\,$eV, (3) emergence of dark energy with the present density of order (a few meV)$^4$ consistent with observations, (4) presence of a long range spin-dependent force, (5) slow-roll inflation after PQ symmetry breaking when conformal coupling to gravity is introduced.

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M. Yoshimura
Wed, 2 Feb 22
9/60

Comments: 10 pages, 3 figures

Density of GeV muons in air showers measured with IceTop [CL]

http://arxiv.org/abs/2201.12635


We present a measurement of the density of GeV muons in near-vertical air showers using three years of data recorded by the IceTop array at the South Pole. Depending on the shower size, the muon densities have been measured at lateral distances between 200 m and 1000 m. From these lateral distributions, we derive the muon densities as functions of energy at reference distances of 600 m and 800 m for primary energies between 2.5 PeV and 40 PeV and between 9 PeV and 120 PeV, respectively. The muon densities are determined using, as a baseline, the hadronic interaction model Sibyll 2.1 together with various composition models. The measurements are consistent with the predicted muon densities within these baseline interaction and composition models. The measured muon densities have also been compared to simulations using the post-LHC models EPOS-LHC and QGSJet-II.04. The result of this comparison is that the post-LHC models together with any given composition model yield higher muon densities than observed. This is in contrast to the observations above 1 EeV where all model simulations yield for any mass composition lower muon densities than the measured ones. The post-LHC models in general feature higher muon densities so that the agreement with experimental data at the highest energies is improved but the muon densities are not correct in the energy range between 2.5 PeV and about 100 PeV.

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R. Abbasi, M. Ackermann, J. Adams, et. al.
Tue, 1 Feb 22
21/73

Comments: 20 pages, 17 captioned figures, submitted to Phys. Rev. D

Muography in Colombia: simulation framework, instrumentation and data analysis [IMA]

http://arxiv.org/abs/2201.11160


We present the Colombo-Argentinian Muography Program for studying inland Latin-American volcanoes. It describes the implementation of a simulation framework covering various factors with different spatial and time scales: the geomagnetic effects at a particular geographic point, the development of extensive air showers in the atmosphere, the propagation through the scanned structure and the detector response. Next, we sketch the criteria adopted for designing, building, and commissioning MuTe: a hybrid Muon Telescope based on a composite detection technique. It combines a hodoscope for particle tracking and a water Cherenkov detector to enhance the muon-to-background-signal separation due to extensive air showers’ soft and multiple-particle components. MuTe also discriminates inverse-trajectory and low-momentum muons by using a picosecond Time-of-Flight system. We also characterise the instrument’s structural (mechanical and thermal) behaviour, discussing preliminary results from the background composition and the telescope-health monitoring variables. Finally, we discuss the implementations of an optimisation algorithm to improve the volcano internal density distribution estimation and machine learning techniques for background rejection.

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J. Peña-Rodríguez, A. Vesga-Ramírez, A. Vásquez-Ramírez, et. al.
Fri, 28 Jan 22
25/64

Comments: N/A