Signatures of Light Massive Relics on nonlinear structure formation

Understand

Cosmologies with Light Massive Relics (LiMRs) as a subdominant component of the dark sector are well-motivated from a particle physics perspective, and can also have implications for the $\sigma_8$ tension between early and late time probes of matter clustering.

• The effects of LiMRs on the Cosmic Microwave Background (CMB) and structure formation on large (linear) scales have been investigated extensively.
• In this paper, we initiate a systematic study of the effects of LiMRs on smaller, nonlinear scales using cosmological $N$-body simulations; focusing on quantities relevant for photometric galaxy surveys.
• For most of our study, we use a particular model of nonthermal LiMRs but the methods developed easily generalize to a large class of models of LiMRs -- we explicitly demonstrate this by considering the Dodelson-Widrow form of the velocity distribution.