Determination of Dark Matter Halo Mass from Dynamics of Satellite Galaxies

Abstract

We show that the mass of a dark matter halo can be inferred from the dynamical status of its satellite galaxies. Using 9 dark-matter simulations of halos like the Milky Way (MW), we find that the present-day substructures in each halo follow a characteristic distribution in the phase space of orbital binding energy and angular momentum, and that this distribution is similar from halo to halo but has an intrinsic dependence on the halo formation history. We construct this distribution directly from the simulations for a specific halo and extend the result to halos of similar formation history but different masses by scaling. The mass of an observed halo can then be estimated by maximizing the likelihood in comparing the measured kinematic parameters of its satellite galaxies with these distributions. We test the validity and accuracy of this method with mock samples taken from the simulations. Using the positions, radial velocities, and proper motions of 9 tracers and assuming observational uncertainties comparable to those of MW satellite galaxies, we find that the halo mass can be recovered to within $\sim$40%. The accuracy can be improved to within $\sim$25% if 30 tracers are used. However, the dependence of the phase-space distribution on the halo formation history sets a minimum uncertainty of $\sim$20% that cannot be reduced by using more tracers. We believe that this minimum uncertainty also applies to any mass determination for a halo when the phase space information of other kinematic tracers is used.

arXiv commentAccepted for publication in ApJ, 18 pages, 13 figures

References in corpus (49)

• Astropy: A Community Python Package for Astronomy
• The cosmological simulation code GADGET-2
• The observed properties of dwarf galaxies in and around the Local Group
• The Galaxy in Context: Structural, Kinematic and Integrated Properties
• Too big to fail? The puzzling darkness of massive Milky Way subhaloes
• From dwarf spheroidals to cDs: Simulating the galaxy population in a LCDM cosmology
• Triaxial Modeling of Halo Density Profiles with High-resolution N-body Simulations
• The Milky Way's Circular Velocity Curve to 60 kpc and an Estimate of the Dark Matter Halo Mass from Kinematics of ~2400 SDSS Blue Horizontal Branch Stars
• Accurate masses for dispersion-supported galaxies
• Eight New Milky Way Companions Discovered in First-Year Dark Energy Survey Data
• Beasts of the Southern Wild: Discovery of nine Ultra Faint satellites in the vicinity of the Magellanic Clouds
• Eight Ultra-faint Galaxy Candidates Discovered in Year Two of the Dark Energy Survey
• A common mass scale for satellite galaxies of the Milky Way
• Accurate universal models for the mass accretion histories and concentrations of dark matter halos
• Density Profiles of Dark Matter Halo are not Universal
• Hundreds of Milky Way Satellites? Luminosity Bias in the Satellite Luminosity Function
• The Halo Occupation Distribution and the Physics of Galaxy Formation
• The Present and Future Mass of the Milky Way Halo
• The Masses of the Milky Way and Andromeda galaxies
• The Dark Matter Halo of the Milky Way, AD 2013
• Galaxy Masses
• "Skinny Milky Way, Please", says Sagittarius
• Masses for the Local Group and the Milky Way
• A timing constraint on the (total) mass of the Large Magellanic Cloud
• The Milky Way's rotation curve out to 100 kpc and its constraint on the Galactic mass distribution
• The Space Motion of Leo I: The Mass of the Milky Way's Dark Matter Halo
• The Missing Massive Satellites of the Milky Way
• The dependence of dark halo clustering on the formation epoch and the concentration parameter
• The rotationally stabilized VPOS and predicted proper motions of the Milky Way satellite galaxies
• A New Faint Milky Way Satellite Discovered in the Pan-STARRS1 3 pi Survey
• A unified model for the spatial and mass distribution of subhaloes
• Resolving Subhaloes' Lives with the Hierarchical Bound-Tracing Algorithm
• Velocity Bias from the Small Scale Clustering of SDSS-III BOSS Galaxies
• At the survey limits: discovery of the Aquarius 2 dwarf galaxy in the VST ATLAS and the SDSS data
• Estimating the dark matter halo mass of our Milky Way using dynamical tracers
• Proper Motions of Dwarf Spheroidal Galaxies from Hubble Space Telescope Imaging. III: Measurement for Ursa Minor
• The satellites of the Milky Way - Insights from semi-analytic modelling in a LambdaCDM cosmology
• Proper Motions of Dwarf Spheroidal Galaxies from Hubble Space Telescope Imaging. I: Method and a Preliminary Measurement for Fornax
• The Orbital Ellipticity of Satellite Galaxies and the Mass of the Milky Way
• First Gaia Local Group Dynamics: Magellanic Clouds Proper Motion and Rotation
• A new spin on disks of satellite galaxies
• Estimating the Galactic Mass Profile in the Presence of Incomplete Data
• Bayesian Mass Estimates of the Milky Way: including measurement uncertainties with hierarchical Bayes
• Spatial and Dynamical Biases in Velocity Statistics of Galaxies
• The Massive Satellite Population of Milky-Way Sized Galaxies
• The orbital PDF: the dynamical state of Milky Way sized haloes and the intrinsic uncertainty in the determination of their masses
• A dynamics-free lower bound on the mass of our galaxy
• What to expect from dynamical modelling of galactic haloes
• Dynamical History of the Local Group in $\Lambda$CDM

Cited by in corpus (20)

• The Milky Way total mass profile as inferred from Gaia DR2
• The mass of the Milky Way from satellite dynamics
• The mass of our Milky Way
• The Circular Velocity Curve of the Milky Way from 5 to 25 kpc using luminous red giant branch star
• Constraining the Milky Way Mass Profile with Phase-Space Distribution of Satellite Galaxies
• Estimating the Mass of the Milky Way Using the Ensemble of Classical Satellite Galaxies
• The stellar halo of isolated central galaxies in the Hyper Suprime-Cam imaging survey
• What to expect from dynamical modelling of galactic haloes II: the spherical Jeans equation
• Using Velocity Dispersion to Estimate Halo Mass: Is the Local Group in Tension with $\Lambda$CDM?
• Evidence for a Massive Andromeda Galaxy Using Satellite Galaxy Proper Motions
• The orbital phase space of contracted dark matter halos
• The effect of Large Magellanic Cloud on the satellite galaxy population in Milky Way analogous Galaxies
• Orbital distribution of infalling satellite halos across cosmic time
• A Versatile and Accurate Method for Halo Mass Determination from Phase-Space Distribution of Satellite Galaxies
• Galactic Mass Estimates using Dwarf Galaxies as Kinematic Tracers
• Determining Satellite Infall Times Using Machine Learning
• Constraining the Milky Way Mass with Its Hot Gaseous Halo
• The Milky Way accretion history compared to cosmological simulations -- from bulge to dwarf galaxy infall
• Warm dark matter model with a few keV mass is bad for the too-big-to-fail problem
• Constraining the shape of Milky Way satellites with distance gradients