Measuring distances to galaxies with globular cluster velocity dispersions

Abstract

Accurate distances are key to obtaining intrinsic properties of astronomical objects such as luminosity or size. Globular clusters (GCs) follow a well-defined relation between their absolute magnitudes and internal stellar velocity dispersions ($\sigma$), offering an independent way to measure distances to their host galaxies via high-resolution spectroscopy. This is reminiscent of the "Faber-Jackson" for elliptical galaxies. However, unlike galaxies, GCs have a very narrow range of mass-to-light ratios and simple star formation histories. Here we show that the GC $M_V-{\text{log}}_{10}(\sigma )$ relation is linear, whose slope is identical for the Milky Way and M31 GC systems. Based on this, we use 94 Milky Way GCs which have distances from Gaia parallaxes, or proper-motion dispersion profiles to derive a "GC velocity dispersion" distance (GCVD) to M31, obtaining $(m-M{)}_0=24.51\pm 0.08$ ($d=798\pm 28$ kpc), in excellent agreement with independent measurements. Combining data for these two galaxies to create a fiducial relation using 296 GCs with high-quality measurements, we obtain a zeropoint uncertainty ($\pm 0.06$ mag) corresponding to a distance uncertainty of $\sim 3\%$. We then use GCVD to obtain a distance to the giant elliptical galaxy NGC\,5128 (Centaurus A), finding $(m-M{)}_0=27.95\pm 0.09$ ($d=3.89\pm 0.16$ Mpc). This is in excellent agreement with, and in some cases more precise than, literature estimates from the tip of the red giant branch or surface brightness fluctuations. We apply GCVD to Local Group galaxies with appropriate data and find good agreement with literature values even in cases with only one GC velocity dispersion measurement.

arXiv commentAccepted for publication in MNRAS

References in corpus (50)

• SciPy 1.0--Fundamental Algorithms for Scientific Computing in Python
• Array Programming with NumPy
• Astropy: A Community Python Package for Astronomy
• emcee: The MCMC Hammer
• The Astropy Project: Building an inclusive, open-science project and status of the v2.0 core package
• Measuring Reddening with SDSS Stellar Spectra and Recalibrating SFD
• The Astropy Project: Sustaining and Growing a Community-oriented Open-source Project and the Latest Major Release (v5.0) of the Core Package
• In the Realm of the Hubble tension $-$ a Review of Solutions
• The SBF Survey of Galaxy Distances. IV. SBF Magnitudes, Colors, and Distances
• Extragalactic Globular Clusters and Galaxy Formation
• A Precise Distance Indicator: Type Ia Supernova Multicolor Light Curve Shapes
• Measurements of the Hubble Constant: Tensions in Perspective
• A catalogue of masses, structural parameters and velocity dispersion profiles of 112 Milky Way globular clusters
• The Magellanic Clouds Photometric Survey: The Large Magellanic Cloud Stellar Catalog and Extinction Map
• Accurate distances to Galactic globular clusters through a combination of Gaia EDR3, HST and literature data
• A Catalog of Globular Cluster Systems: What Determines the Size of a Galaxy's Globular Cluster Population?
• Star Clusters in M31: II. Old Cluster Metallicities and Ages from Hectospec Data
• Two Planes of Satellites in the Centaurus A Group
• Star Clusters in M31: I. A Catalog and a Study of the Young Clusters
• The Globular Cluster System of NGC 5128 II. Ages, Metallicities, Kinematics, and Formation
• A Review of the Distance and Structure of the Large Magellanic Cloud
• Star Clusters in M31: V. Internal Dynamical Trends: Some Troublesome, Some Reassuring
• The Line-of-Sight Depth of Populous Clusters in the Small Magellanic Cloud
• The Discovery of Cepheids and a Distance to NGC 5128
• A 2dF spectroscopic study of globular clusters in NGC 5128: Probing the formation history of the nearest giant Elliptical
• Chemical composition and constraints on mass loss for globular clusters in dwarf galaxies: WLM and IKN
• Detailed abundance analysis from integrated high-dispersion spectroscopy: Globular clusters in the Fornax Dwarf Spheroidal
• An updated survey of globular clusters in M 31. I. Classification and radial velocity for 76 candidate clusters
• Kinematics of Outer Halo Globular Clusters in M31
• The Black Hole in the Most Massive Ultracompact Dwarf Galaxy M59-UCD3
• The Kinematics and Dynamics of the Globular Clusters and the Planetary Nebulae of NGC 5128
• Absolute V-band magnitudes and mass-to-light ratios of Galactic globular clusters
• HST Colour-Magnitude Diagrams of Six Old Globular Clusters in the LMC
• Structural Parameters and Dynamical Masses for Globular Clusters in M33
• An old, metal-poor globular cluster in Sextans A and the metallicity floor of globular cluster systems
• Variations in Star Formation History and the Red Giant Branch Tip
• Observational Evidence for a Dark Side to NGC5128's Globular Cluster System
• Integrated Light Chemical Tagging Analyses of Seven M31 Outer Halo Globular Clusters from the Pan-Andromeda Archaeological Survey
• Using the Tip of the Red Giant Branch as a Distance Indicator in the Near Infrared
• Globular cluster systems and galaxy formation
• Upper limits on the presence of central massive black holes in two ultra-compact dwarf galaxies in Centaurus A
• Dynamical masses and mass-to-light ratios of resolved massive star clusters -- II. Results for 26 star clusters in the Magellanic Clouds
• The chemical composition of globular clusters in the Local Group
• Detailed abundance analysis of globular clusters in the Local Group: NGC 147, NGC 6822, and Messier 33
• NGC 5128 globular cluster candidates out to 150 kpc: a comprehensive catalog from Gaia and ground based data
• The Globular Cluster System of NGC 6822
• Deriving ages and horizontal branch properties of integrated stellar populations
• Quantifying Uncertainties on the Tip of the Red Giant Branch Method
• Assessing potential cluster Cepheids from a new distance and reddening parameterization and 2MASS photometry
• New Velocity Measurements of NGC 5128 Globular Clusters out to 130 kpc: Outer Halo Kinematics, Substructure and Dynamics

Cited by in corpus (8)

• A too-many dwarf galaxy satellites problem in the M83 group
• Revisiting the globular clusters of NGC1052-DF2
• Looking into the faintEst WIth MUSE (LEWIS): Exploring the nature of ultra-diffuse galaxies in the Hydra-I cluster IV. A study of the Globular Cluster population in four UDGs
• A new way to measure the distance to NGC1052-DF2
• One Stream or Two -- Exploring Andromeda's North West Stream
• Catalogue of central stars of extragalactic planetary nebulae
• Properties of the Lower Segment of M31's North West Stream
• Semiresolved Stellar Populations as Distance Indicators