Late-time dark matter oscillations and the core-cusp problem

Journal of High Energy Physics

James M. Cline¹  Matteo Puel¹  Guillermo Gambini¹  Samuel D. McDermott² 

[1]McGill University, Department of Physics

[2]Theory Division, Fermi National Accelerator Laboratory

关键词: Beyond Standard Model;    Cosmology of Theories beyond the SM;    Effective;    Field Theories;   

DOI  :  10.1007/JHEP04(2021)223

来源: DOAJ

【 摘 要 】

Abstract The core-cusp problem persists as an unresolved tension between the pre- dictions of ΛCDM cosmology and observations of dark matter (DM) profiles in dwarf spheroidal and other galaxies. We present a novel scenario for converting cusps into cores through reactivation of DM annihilation in galaxies at late times. This can happen in asymmetric DM models when there is a very small DM-number violating mass term that causes oscillations between DM and its antiparticle. Using analytic methods as well as gravitational N-body simulations, we show that this mechanism can robustly eliminate cusps from galactic DM profiles for light fermionic DM of mass m χ ∼ (0.1 − 1) GeV and a lighter mediator into which the DM can annihilate. We identify regions of parameter space where annihilation of DM particles is more efficient than elastic scattering at reducing the inner density of the DM profile. Dark matter annihilation is therefore a qualitatively distinct alternative to the mechanism of elastic self-interacting dark matter for addressing the cusp-core problem.

【 授权许可】

Unknown