English

Jeans Analysis for Dwarf Spheroidal Galaxies in Wave Dark Matter

Astrophysics of Galaxies 2017-04-12 v2 Cosmology and Nongalactic Astrophysics

Abstract

Although still under debate, observations generally suggest that dwarf spheroidal (dSph) galaxies exhibit large constant-density cores in the centers, which can hardly be explained by dissipationless cold dark matter simulations without baryonic feedback. Wave dark matter (ψDM{\psi {\rm DM}}), characterized by a single parameter, the dark matter particle mass mψm_{\psi}, predicts a central soliton core in every galaxy arising from quantum pressure against gravity. Here we apply Jeans analysis assuming a soliton core profile to the kinematic data of eight classical dSphs so as to constrain mψm_{\psi}, and obtain mψ=1.180.24+0.28×1022eVm_{\psi}=1.18_{-0.24}^{+0.28}\times10^{-22}{\,\rm eV} and mψ=1.790.33+0.35×1022eV (2σ)m_{\psi}=1.79_{-0.33}^{+0.35}\times10^{-22}{\,\rm eV}~(2\sigma) using the observational data sets of Walker et al. (2007) and Walker et al. (2009b), respectively. We show that the estimate of mψm_{\psi} is sensitive to the dSphs kinematic data sets and is robust to various models of stellar density profile. We also consider multiple stellar subpopulations in dSphs and find consistent results. This mass range of mψm_{\psi} is in good agreement with other independent estimates, such as the high-redshift luminosity functions, the reionization history, and the Thomson optical depth to the cosmic microwave background.

Keywords

Cite

@article{arxiv.1606.09030,
  title  = {Jeans Analysis for Dwarf Spheroidal Galaxies in Wave Dark Matter},
  author = {Shu-Rong Chen and Hsi-Yu Schive and Tzihong Chiueh},
  journal= {arXiv preprint arXiv:1606.09030},
  year   = {2017}
}

Comments

12 pages, 11 figures, 2 tables, add appendix B about the joint analysis, submitted to MNRAS