The Effect of Dark Matter-Dark Radiation Interactions on Halo Abundance: A Press-Schechter Approach
Abstract
We study halo mass functions with the Press-Schechter formalism for interacting dark matter models, where matter power spectra are damped due to dark acoustic oscillations in the early universe. After adopting a smooth window function, we calibrate the analytical model with numerical simulations from the “effective theory of structure formation” (ETHOS) project and fix the model parameters in the high-mass regime, M h ≳ 3 × 1010 M ⊙. We also perform high-resolution cosmological simulations with halo masses down to M h ∼ 108 M ⊙ to cover a wide mass range for comparison. Although the model is calibrated with ETHOS1 and cold dark matter simulations for high halo masses at redshift z = 0, it successfully reproduces simulations for two other ETHOS models in the low-mass regime at low and high redshifts. As an application, we compare the cumulative number density of halos to that of observed galaxies at z = 6, and find that the interacting dark matter models with a kinetic decoupling temperature below 0.5 keV is disfavored. We also perform the abundance-matching analysis and derive the stellar-halo mass relation for these models at z = 4. Suppression in halo abundance leads to less massive halos that host observed galaxies in the stellar mass range {M}* ≃ {10}5{--}{10}7 {M}⊙ .
- Publication:
-
The Astrophysical Journal
- Pub Date:
- March 2019
- DOI:
- 10.3847/1538-4357/ab0824
- arXiv:
- arXiv:1810.11040
- Bibcode:
- 2019ApJ...874..101S
- Keywords:
-
- cosmology: theory;
- dark matter;
- galaxies: formation;
- galaxies: halos;
- methods: numerical;
- Astrophysics - Cosmology and Nongalactic Astrophysics;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 9 pages, 7 figures, published version