Galactic rotation curves vs. ultralight dark matter

by Nitsan Bar

Wednesday 23 Mar 2022, 16:30 → 18:30 Europe/Zurich

4/3-006 - TH Conference Room (CERN)

Analytic arguments and numerical simulations show that bosonic ultra-light dark matter (ULDM) would form cored density distributions (`solitons') at the centers of galaxies. We look for and place observational constraints on the imprint of these soliton cores in rotation-dominated galaxies. We find a conservative, model-independent constraint which disfavors the soliton-host halo relation found in numerical simulations over a broad range of ULDM particle mass $m$. Combining the observational constraints with theoretical arguments for the efficiency of soliton formation via gravitational dynamical relaxation, our results disfavor ULDM from comprising 100% of the total cosmological dark matter in the range $10^{-24} <  m <  10^{20}$ eV. This probe is sensitive to ULDM playing a fraction of DM, down to $f \sim 0.3$. Based on 2111.03070 and previous work, 1805.00122, 1903.03402, 1905.11745.