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Title: Millicharged relics reveal massless dark photons
A bstract The detection of massless kinetically-mixed dark photons is notoriously difficult, as the effect of this mixing can be removed by a field redefinition in vacuum. In this work, we study the prospect of detecting massless dark photons in the presence of a cosmic relic directly charged under this dark electromagnetism. Such millicharged particles, in the form of dark matter or dark radiation, generate an effective dark photon mass that drives photon-to-dark photon oscillations in the early universe. We also study the prospect for such models to alleviate existing cosmological constraints on massive dark photons, enlarging the motivation for direct tests of this parameter space using precision terrestrial probes.  more » « less
Award ID(s):
2210498 1915409
PAR ID:
10437888
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Journal of High Energy Physics
Volume:
2023
Issue:
5
ISSN:
1029-8479
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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