Constraining the primordial curvature perturbation using dark matter substructure
Abstract
We investigate the primordial curvature perturbation by the observation of dark matter substructure. Assuming a bump in the spectrum of the curvature perturbation in the wavenumber of k>1 Mpc^{-1}, we track the evolution of the host halo and subhalos in a semi-analytic way. Taking into account possible uncertainties in the evaluation of the tidal stripping effect on the subhalo growth, we find a new robust bound on the curvature perturbation with a bump from the number of observed dwarf spheroidal galaxies in our Galaxy and the observations of the stellar stream. The upper limit on the amplitude of the bump is O(10^{-7}) for k~10^3 Mpc^{-1}. Furthermore we find the boost factor, which is crucial for the indirect detection of dark matter signals, is up to O(10^4) due to the bump that is allowed in the current observational bounds.
Keywords
Cite
@article{arxiv.2207.05747,
title = {Constraining the primordial curvature perturbation using dark matter substructure},
author = {Shin'ichiro Ando and Nagisa Hiroshima and Koji Ishiwata},
journal= {arXiv preprint arXiv:2207.05747},
year = {2022}
}
Comments
11 pages, 9 figures, published version