Measuring Consistent Masses for 25 Milky Way Globular Clusters

Abstract

We present central velocity dispersions, masses, mass to light ratios ($M/L$s), and rotation strengths for 25 Galactic globular clusters. We derive radial velocities of 1951 stars in 12 globular clusters from single order spectra taken with Hectochelle on the MMT telescope. To this sample we add an analysis of available archival data of individual stars. For the full set of data we fit King models to derive consistent dynamical parameters for the clusters. We find good agreement between single mass King models and the observed radial dispersion profiles. The large, uniform sample of dynamical masses we derive enables us to examine trends of $M/L$ with cluster mass and metallicity. The overall values of $M/L$ and the trends with mass and metallicity are consistent with existing measurements from a large sample of M31 clusters. This includes a clear trend of increasing $M/L$ with cluster mass, and lower than expected $M/L$s for the metal-rich clusters. We find no clear trend of increasing rotation with increasing cluster metallicity suggested in previous work.

Accepted by AJ; 17 pages 14 figures

References in corpus (14)

• A systematic variation of the stellar initial mass function in early-type galaxies
• The Nature of UCDs: Internal Dynamics from an Expanded Sample and Homogeneous Database
• Star Clusters in M31: I. A Catalog and a Study of the Young Clusters
• Clean Kinematic Samples in Dwarf Spheroidals: An Algorithm for Evaluating Membership and Estimating Distribution Parameters When Contamination is Present
• Dynamical masses of ultra-compact dwarf galaxies in Fornax
• Halo globular clusters observed with AAOmega: dark matter content, metallicity and tidal heating
• Na-O Anticorrelation and HB. II. The Na-O anticorrelation in the globular cluster NGC 6752
• Central rotations of Milky Way Globular Clusters
• Na-O Anticorrelation and HB. IV. Detection of He-rich and He-poor stellar populations in the globular cluster NGC 6218
• 2D Fokker-Planck models of rotating clusters
• Explaining the mass-to-light ratios of globular clusters
• The Global Kinematics of the Globular Cluster M92
• Mass segregation in the outer halo globular cluster Palomar 14
• Probing Mass Segregation in NGC 6397

Cited by in corpus (16)

• A stellar census in globular clusters with MUSE: The contribution of rotation to cluster dynamics studied with 200 000 stars
• N-body modeling of globular clusters: Masses, mass-to-light ratios and intermediate-mass black holes
• Galactic Dark Matter Halos and Globular Cluster Populations. III: Extension to Extreme Environments
• The ultracompact nature of the black hole candidate X-ray binary 47 Tuc X9
• Rotation in young massive star clusters
• Revisiting nucleosynthesis in globular clusters: the case of NGC 2808 and the role of He and K
• A Chemical Composition Survey of the Iron-Complex Globular Cluster NGC 6273 (M 19)
• Biases in the inferred mass-to-light ratio of globular clusters: no need for variations in the stellar mass function
• The Supersonic Project: Shining Light on SIGOs - a New Formation Channel for Globular Clusters
• Proper motions and structural parameters of the Galactic globular cluster M71
• Probing the formation history of the nuclear star cluster at the Galactic Centre with millisecond pulsars
• Chemical Abundances in NGC 5053: A Very Metal-Poor and Dynamically Complex Globular Cluster
• MONDian dynamical modeling of NGC 288 with $\beta \ne 0$
• Evolution of the Mass and Luminosity Functions of Globular Star Clusters
• Photometric Detection of Multiple Populations in Globular Clusters Using Integrated Light
• Biases in the determination of dynamical parameters of star clusters: today and in the Gaia era