Galactic rotation curves versus ultralight dark matter: A systematic comparison with SPARC data
Nitsan Bar, Kfir Blum, Chen Sun
Abstract
We look for and place observational constraints on the imprint of ultralight dark matter (ULDM) soliton cores in rotation-dominated galaxies. Extending previous analyses, we find a conservative constraint which disfavors the soliton-host halo relation found in some numerical simulations over a broad range in the ULDM particle mass $m$. Combining the observational constraints with theoretical arguments for the efficiency of soliton formation via gravitational dynamical relaxation and assuming that the soliton-halo relation is correct, our results disfavor ULDM from comprising 100% of the total cosmological dark matter in the range ${10}^{\ensuremath{-}24}\text{ }\text{ }\mathrm{eV}\ensuremath{\lesssim}m\ensuremath{\lesssim}{10}^{\ensuremath{-}20}\text{ }\text{ }\mathrm{eV}$. The constraints probe the ULDM fraction down to $f\ensuremath{\lesssim}0.3$ of the total dark matter.