Dark matter kinetic decoupling with a light particle

Ayuki Kamada, Tomo Takahashi
2018 Journal of Cosmology and Astroparticle Physics  
We argue that the acoustic damping of the matter power spectrum is not a generic feature of the kinetic decoupling of dark matter, but even the enhancement can be realized depending on the nature of the kinetic decoupling when compared to that in the standard cold dark matter model. We consider a model that exhibits a sudden kinetic decoupling and investigate cosmological perturbations in the standard cosmological background numerically in the model. We also give an analytic discussion in a
more » ... lified setup. Our results indicate that the nature of the kinetic decoupling could have a great impact on small scale density perturbations.
doi:10.1088/1475-7516/2018/01/047 fatcat:vuyuniasargbvpydvymfek5yjy