Dark photon oscillations in our inhomogeneous Universe and their imprint on 21-cm observations

by Siddharth Mishra-Sharma (New York University)

Friday 13 Nov 2020, 14:00 → 16:00 America/New_York

Kinetically-mixed dark photons can oscillate to Standard Model photons, and vice versa. These oscillations can be resonantly enhanced when the plasma mass of the Standard Model photon, which tracks the cosmic electron number density, matches the dark photon mass. I will present an analytic formalism for computing the effect of dark photon oscillations taking into account inhomogeneities in the plasma mass in our Universe. I will then use this formalism to derive new bounds on ultralight dark photons from spectral distortions of the CMB. Finally, I will discuss how dark photon-to-photon oscillations could be imprinted in observations of the redshifted 21-cm hydrogen line.

111320_MishraSharma_PANDEMIC.mp4

MishraSharma_BSMPANDEMIC.pdf