Implications of mirror dark matter kinetic mixing for CMB anisotropies

TL;DR

Mirror dark matter with photon-mirror photon kinetic mixing can influence CMB anisotropies, notably suppressing higher odd peaks, and could be detectable by the PLANCK mission if the mixing strength is around 10^{-9}.

Contribution

This paper analyzes how kinetic mixing in mirror dark matter models affects CMB anisotropies, highlighting a potential observable signature for future experiments.

Findings

Suppression of third and higher odd peaks in CMB spectrum due to kinetic mixing.

Detectability of this effect by PLANCK if kinetic mixing strength is ≥ 10^{-9}.

Mirror dark matter can explain direct detection experiments like DAMA, CoGeNT, and CRESST-II.

Abstract

Mirror dark matter is a dissipative and self-interacting multiparticle dark matter candidate which can explain the DAMA, CoGeNT and CRESST-II direct detection experiments. This explanation requires photon-mirror photon kinetic mixing of strength $\epsilon \sim 10^{-9}$. Mirror dark matter with such kinetic mixing can potentially leave distinctive signatures on the CMB anisotropy spectrum. We show that the most important effect of kinetic mixing on the CMB anisotropies is the suppression of the height of the third and higher odd peaks. If $\epsilon \stackrel{>}{\sim} 10^{-9}$ then this feature can be observed by the PLANCK mission in the near future.