Dark matter kinetic decoupling with a light particle

Abstract

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 simplified setup. Our results indicate that the nature of the kinetic decoupling could have a great impact on small scale density perturbations.

19 pages, 7 figures

References in corpus (7)

• Using the Milky Way satellites to study interactions between cold dark matter and radiation
• Cosmological bounds on dark matter-neutrino interactions
• Scattering, Damping, and Acoustic Oscillations: Simulating the Structure of Dark Matter Halos with Relativistic Force Carriers
• Dark matter-radiation interactions: the impact on dark matter haloes
• Residual Non-Abelian Dark Matter and Dark Radiation
• Long-lived Light Mediator to Dark Matter and Primordial Small Scale Spectrum
• The effects of the small-scale behaviour of dark matter power spectrum on CMB spectral distortion

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