Amplifying Non-Resonant Production of Dark Sector Particles in Scattering Dominance Regime

Abstract

We investigate the enhancement of dark sector particle production within the scattering dominant regime. These particles typically exhibit a slight mixing with Standard Model particles through various portals, allowing for their generation through in-medium oscillation from Standard Model particle sources. Our analysis reveals that in the scattering dominance regime, with a significantly smaller scattering mean free path ${\lambda }_{\mathrm{sca}}$ compared to the absorption mean free path ${\lambda }_{\mathrm{abs}}$, the nonresonant production of sterile states can experience an enhancement by a factor of ${\lambda }_{\mathrm{abs}}/{\lambda }_{\mathrm{sca}}$. This phenomenon is demonstrated within the context of kinetic mixing dark photon production at a reactor, precisely satisfying this condition. By incorporating this collisional enhancement, we find that the current sensitivity to the mixing parameter $\epsilon$ for dark photons in the TEXONO experiment can be significantly improved across a range spanning from tens of eV to MeV. This advancement establishes the most stringent laboratory constraint within this mass spectrum for the dark photon. Sterile neutrino production, however, does not exhibit such enhancement, either due to the failure to meet the scattering dominance criterion or the neutrino damping in resonant production.

8 pages, 4 figures, PRD accepted

References in corpus (10)

• A Theory of Dark Matter
• Secluded WIMP Dark Matter
• Dark photon limits: a handbook
• Helioscope Bounds on Hidden Sector Photons
• Spectroscopy as a test of Coulomb's law - A probe of the hidden sector
• Probing a Very Narrow $Z^{\prime }$ Boson with CDF and D0 Data
• Supernova bound on keV-mass sterile neutrinos reexamined
• Explaining PAMELA and WMAP data through Coannihilations in Extended SUGRA with Collider Implications
• Dark Photon Dark Matter without Stueckelberg Mass
• Enhanced long-lived dark photon signals at lifetime frontier detectors