We use the galaxy rotation curves in the SPARC database to compare 9 different dark matter and modified gravity models on an equal footing, paying special attention to the stellar mass-to-light ratios. We compare three non-interacting dark matter models, a self interacting DM (SIDM) model, two hadronically interacting DM (HIDM) models, and three modified Newtonian dynamics type models: MOND, Radial Acceleration Relation (RAR) and a maximal-disk model. The models with DM-gas interactions generate a disky component in the dark matter, which significantly improves the fits to the rotation curves compared to all other models except an Einasto halo; the MOND-type models give significantly worse fits.
@article{arxiv.2105.00119,
title = {Galaxy rotation curves disfavor traditional and self-interacting dark matter halos, preferring a disk component or Einasto function},
author = {Nicolas Loizeau and Glennys R. Farrar},
journal= {arXiv preprint arXiv:2105.00119},
year = {2021}
}
Comments
We fixed a typo in eq A3, added fig 6 and updated fig 1 and fig 8 with two galaxy subsets of high and low inclinations