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arXiv · 2009.03899

Edges and Endpoints in 21-cm Observations from Resonant Photon Production

Andrea Caputo·Hongwan Liu·Siddharth Mishra-Sharma·Maxim Pospelov·Joshua T. Ruderman·Alfredo Urbano
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Abstract

We introduce a novel class of signatures---spectral edges and endpoints---in 21-cm measurements resulting from interactions between the standard and dark sectors. Within the context of a kinetically mixed dark photon, we demonstrate how resonant dark photon-to-photon conversions can imprint distinctive spectral features in the observed 21-cm brightness temperature, with implications for current, upcoming, and proposed experiments targeting the cosmic dawn and the dark ages. These signatures open up a qualitatively new way to look for physics beyond the Standard Model using 21-cm observations.

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Andrea Caputo, Hongwan Liu, Siddharth Mishra-Sharma, Maxim Pospelov, Joshua T. Ruderman, Alfredo Urbano. 2020-09-08. Edges and Endpoints in 21-cm Observations from Resonant Photon Production. https://doi.org/10.1103/physrevlett.127.011102

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