Investigating Dynamical Properties of Globular Clusters through a Family of Lowered Isothermal Models

Abstract

To investigate the dynamical properties of globular clusters, the surface brightness and kinematic data were collected and fitted to a family of lowered isothermal models called LIMEPY models. For 18 studied globular clusters, the amounts of concentration, truncation, and anisotropy were determined. In addition, the cluster mass, half-mass radius, distance, and mass-to-light ratio were also obtained. In general, LIMEPY models could describe these clusters well. Among these 18 clusters, NGC 5139, NGC 6388, and NGC 7078 were claimed to be candidates to host intermediate-mass black holes in literature. The models could not appropriately fit the central proper-motion velocity dispersion of NGC 5139 and the slope of proper-motion velocity-dispersion profile of NGC 6388. Thus, more dedicated models with intermediate-mass black holes or a group of stellar-mass black holes at cluster centers may need to be considered. Considering NGC 7078, our model with some degree of anisotropy can fit the data. Finally, the strong concentration-truncation anti-correlation and truncation-semimajor-axis correlation were revealed, which could be the observational imprint of the dynamical evolution of globular clusters.

15 pages, 9 figures, 3 tables, published in MNRAS

References in corpus (17)

• Accurate distances to Galactic globular clusters through a combination of Gaia EDR3, HST and literature data
• The nucleus of the Sagittarius dSph galaxy and M54: a window on the process of galaxy nucleation
• 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
• HST Proper Motions and Stellar Dynamics in the Core of the Globular Cluster 47 Tucanae
• Hubble Space Telescope proper motion (HSTPROMO) catalogs of Galactic globular clusters. II. Kinematic profiles and maps
• The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters. XXIII. Proper-motion catalogs and internal kinematics
• A stellar-mass black hole population in the globular cluster NGC 6101?
• Intermediate Mass Black Hole Induced Quenching of Mass Segregation in Star Clusters
• Exploring the outskirts of globular clusters: the peculiar kinematics of NGC 3201
• The orbital anisotropy profiles of nearby globular clusters from Gaia Data Release 2
• The dynamics of the globular cluster NGC3201 out to the Jacobi radius
• Hunting for intermediate-mass black holes in globular clusters: an astrometric study of NGC 6441
• The Donor of the Black-Hole X-Ray Binary MAXI J1820+070
• The WAGGS project -- III. Discrepant mass-to-light ratios of Galactic globular clusters at high metallicity
• Central kinematics of the Galactic globular cluster M80
• Truncated $\gamma$-exponential models for tidal stellar systems

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