2026/03/31 by Dafa Wardana, Kohei Hayashi, Masashi Chiba +1 · 1 citation
Physics and Astronomy · #astro-ph.GA
Accepted for publication in ApJ
arxiv created 2026/07/31 · arxiv updated 2026/08/03
We investigate how diversity in the core--halo mass relation and the inclusion of higher-order velocity moments affect constraints on the fuzzy dark matter particle mass (mψ) inferred from the internal kinematics of dwarf galaxies. Using stellar line-of-sight velocities and projected positions for eight Milky Way dwarf spheroidal galaxies, we model their dark matter halos as solitonic cores embedded within outer Navarro--Frenk--White envelopes. We apply both second- and fourth-order Jeans analyses to derive the posterior distribution of mψ. Our results show that there are two ranges of mψ consistent with the observed kinematics: log10(mψ/eV) = -19.72+0.64-0.56, and a narrower low-mass window log10(mψ/eV) = -21.81+0.39-0.26, both within the 68% credible intervals. The latter becomes prominent only when core--halo diversity is taken into account, which highlights the sensitivity of the inferred fuzzy dark matter particle mass constraints to our understanding of the core--halo relation. Future observations, providing larger stellar samples and more precise kinematic measurements, will be essential for clarifying the allowed parameter space of fuzzy dark matter.