Gravothermal Solutions of SIDM Halos: Mapping from Constant to Velocity-dependent Cross Section
Abstract
The scale-free gravothermal fluid formalism has long proved effective in describing the evolution of self-interacting dark matter halos with a constant dark matter particle cross section. However, whether the gravothermal fluid solutions match numerical simulations for velocity-dependent cross-section scenarios remains untested. In this work, we provide a fast mapping method that relates the constant-cross-section gravothermal solution to models with arbitrary velocity dependence in the cross section. We show that the gravothermal solutions after mapping are in good agreement with AREPO N-body simulation results. We illustrate the power of this approach by applying this fast mapping method to a halo hosting a low-surface-brightness galaxy, UGC 128. We show that this fast mapping method can be used to constrain free parameters in a physically motivated cross-section model and illustrate the parameter space favored by the rotation curve measurement.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- March 2023
- DOI:
- 10.3847/1538-4357/acbd49
- arXiv:
- arXiv:2205.02957
- Bibcode:
- 2023ApJ...946...47Y
- Keywords:
-
- Dark matter;
- Milky Way dark matter halo;
- 353;
- 1049;
- Astrophysics - Cosmology and Nongalactic Astrophysics
- E-Print:
- 20 pages, 11 figures