A dynamics-free lower bound on the mass of our galaxy

Abstract

We use a sample of Milky Way (MW) analogs for which we have stellar and disk gas mass measurements, published measurements of halo gas masses of the MW and of similar galaxies, and the well-established value of the cosmological baryon fraction to place a lower bound on the mass of the Galaxy of $7.7\times 10^{11}{M}_{\odot }$ and estimate that the mass is likely to be $\ge 1.2\times 10^{12}$ M${}_{\odot }$. Although most dynamical analyses yield measurements consistent with these results, several recent studies have advocated for a total mass well below $10^{12}{M}_{\odot }$. We reject such low mass estimates because they imply a Galactic baryon matter fraction significantly above the universal value. Convergence between dynamical mass estimates and those based on the baryonic mass is an important milestone in our understanding of galaxies.

Accepted for publication in MNRAS

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Cited by in corpus (9)

• The Hestia project: simulations of the Local Group
• The Mass of the Milky Way from the H3 Survey
• The sum of the masses of the Milky Way and M31: a likelihood-free inference approach
• Determination of Dark Matter Halo Mass from Dynamics of Satellite Galaxies
• The Smith Cloud: surviving a high speed transit of the Galactic disc
• Revisiting FUSE O VI Emission in Galaxy Halos
• Populating The Milky Way: Characterising Planet Demographics by Combining Galaxy Formation Simulations and Planet Population Synthesis Models
• An Empirical Determination of the Dependence of the Circumgalactic Mass Cooling Rate and Feedback Mass Loading Factor on Galactic Stellar Mass
• Quantifying the Milky Way, LMC and their interaction using all-sky kinematics of outer halo stars