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A<sc>bstract</sc> One contribution to any dark sector’s abundance comes from its gravitational production during inflation. If the dark sector is weakly coupled to the inflaton and the Standard Model, this can be its only production mechanism. For non-interacting dark sectors, such as a free massive fermion or a free massive vector field, this mechanism has been studied extensively. In this paper we show, via the example of dark massive QED, that the presence of interactions can result in a vastly different mass for the dark matter (DM) particle, which may well coincide with the range probed by upcoming experiments. In the context of dark QED we study the evolution of the energy density in the dark sector after inflation. Inflation produces a cold vector condensate consisting of an enormous number of bosons, which via interesting processes — Schwinger pair production, strong field electromagnetic cascades, and plasma dynamics — transfers its energy to a small number of “dark electrons” and triggers thermalization of the dark sector. The resulting dark electron DM mass range is from 50 MeV to 30 TeV, far different from both the 10−5eV mass of the massive photon dark matter in the absence of dark electrons, and from the 109GeV dark electron mass in the absence of dark photons. This can significantly impact the search strategies for dark QED and, more generally, theories with a self-interacting DM sector. In the presence of kinetic mixing, a dark electron in this mass range can be searched for with upcoming direct detection experiments, such as SENSEI-100g and OSCURA.
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This content will become publicly available on March 1, 2026
Adiabatic conversion of ALPs into dark photon dark matter
A<sc>bstract</sc> We introduce a mechanism by which a misaligned ALP can be dynamically converted into a dark photon in the presence of a background magnetic field. An abundance of non-relativistic ALPs will convert to dark photons with momentum of order the inhomogeneities in the background field; therefore a highly homogeneous field will produce non-relativistic dark photons without relying on any redshifting of their momenta. Taking hidden sector magnetic fields produced by a first order phase transition, the mechanism can reproduce the relic abundance of dark matter for a wide range of dark photon masses down to 10−13eV.
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- Award ID(s):
- 2210361
- PAR ID:
- 10591402
- Publisher / Repository:
- JHEP
- Date Published:
- Journal Name:
- Journal of High Energy Physics
- Volume:
- 2025
- Issue:
- 3
- ISSN:
- 1029-8479
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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