eV Hubble Scale Inflation with Radiative Plateau: Very light Inflaton, Reheating & Dark Matter in B-L Extensions [CL]

http://arxiv.org/abs/2203.03670


We study radiative plateau-like inflation \& Z${BL}$-portal freeze-in fermionic dark matter (DM) in minimal (B-L) extended model. The U(1)${B-L}$ Higgs, responsible for heavy neutrino masses, also drives inflation in early universe, thanks to radiative corrections from the heavy neutrinos \& the Z${BL}$ boson. The benchmark parameters (U(1)${B-L}$ gauge coupling $g_{B-L}\sim10^{-4}$) makes it within the reach of current and future lifetime frontier searches (FASER and FASER 2 at the LHC, SHiP, Belle II, LHCb, etc.) in context to light Z${BL}$ candidates and freeze-in dark matter. For such benchmark points, the Hubble scale of inflation ($H{inf}$) is required to be very low ($H_{inf} \sim \mathcal{O}(100)$ eV) \& the inflaton turns out to be of very light mass ($\mathcal{O}(1)$ eV), and consequently the decay width of inflaton is small. We investigate the \it{2-field-system} still find that sufficient reheating occurs along the the Standard Model Higgs direction component of the tangent along the trajectory in the field space, near the water-fall of the potential. For our parameter choices, along with the chosen DM mass $m_\chi\sim\mathcal{O}(10)$ GeV, we find the DM ($\chi$) is produced via freeze-in.

Read this paper on arXiv…

A. Ghoshal, N. Okada and A. Paul
Wed, 9 Mar 22
31/68

Comments: 19 pages, 5 figures