Rich structure of non-thermal relativistic CMB spectral distortions from high energy particle cascades at redshifts $z\lesssim 2\times 10^5$

Sandeep Kumar Acharya, Rishi Khatri

It is generally assumed that for energy injection before recombination, all of the injected energy is dissipated as heat in the baryon-photon plasma, giving rise to the $y$-type, $…