The puzzling dynamical status of the core of the globular cluster NGC 6752

Abstract

We have used high resolution WFPC2-HST and ground based Wide Field images to determine the center of gravity and construct an extended radial density and brightness profile of the cluster NGC 6752 including, for the first time, detailed star counts in the very inner region. The barycenter of the 9 innermost X-ray sources detected by Chandra is located only 1.9" off the new center of gravity. Both the density and the brightness profile of the central region are best fitted by a double King model, suggesting that NGC 6752 is experiencing a post-core collapse "bounce". Taking advantage from our new optical data, we discuss the puzzling nature of the accelerations displayed by the innermost millisecond pulsars detected in this cluster. We discuss two possible origins to the accelerations: 1) the overall cluster gravitational potential which would require a central projected mass to light ratio of order 6-7 and the existence of a few thousand solar masses of low-luminosity matter within the inner 0.08 pc of NGC6752; 2) the existence of a local perturber(s) of the pulsar dynamics, such as a recently proposed binary black hole of intermediate (100-$200 Msun) mass.

arXiv comment24 pages, 5 figures (accepted on ApJ)

References in corpus (18)

• Internal Dynamics of Globular Clusters
• The giant, horizontal and asymptotic branches of galactic globular clusters. I. The catalog, photometric observables and features
• Monte Carlo Simulations of Globular Cluster Evolution. III. Primordial Binary Interactions
• On the central structure of M15
• Dynamics and Interactions of Binaries and Neutron Stars in Globular Clusters
• Blue Straggler Stars: The Spectacular Population in M80
• Discovery of short-period binary millisecond pulsars in four globular clusters
• Addendum: "Hubble Space Telescope Evidence for an Intermediate-Mass Black Hole in the Globular Cluster M15: II. Kinematical Analysis and Dynamical Modeling"
• Optical Identification of Multiple Faint X-ray Sources in the Globular Cluster NGC 6752: Evidence for Numerous Cataclysmic Variables
• Blue Stragglers, Young White Dwarfs and UV-excess stars in the core of 47 Tuc
• Timing of Millisecond Pulsars in NGC 6752: Evidence for a High Mass-to-Light Ratio in the Cluster Core
• The case of PSR J1911-5958A in the outskirts of NGC 6752: signature of a black hole binary in the cluster core?
• Globular Cluster Photometry with the Hubble Space Telescope. V. WFPC2 Study of M15's Central Density Cusp
• Deep HST/FOC Imaging of the Central Density Cusp of the Globular Cluster M15
• Retention Fractions for Globular Cluster Neutron Stars
• VLT Observations of the Peculiar Globular Cluster NGC6712, III: The Evolved Stellar Population
• Central Proper-Motion Kinematics of NGC 6752
• Addendum: "The Dynamics of M15: Observations of the Velocity Dispersion Profile and Fokker-Planck Models" (ApJ, 481, 267 [1997])

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• Surface Brightness Profiles of Galactic Globular Clusters from Hubble Space Telescope Images
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• Pulsars as Tools for Fundamental Physics and Astrophysics
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• A multi-wavelength survey of NGC\,6752: X-ray counterparts, two new dwarf novae, and a core-collapsed radial profile
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• A complete census of $H\alpha$ emitters in NGC 6397
• G2C2-III: Structural parameters for Galactic globular clusters in SDSS passbands
• Blue Straggler Stars in Globular Clusters: a powerful tool to probe the internal dynamical evolution of stellar systems
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• Prospects for intermediate mass black hole binary searches with advanced gravitational-wave detectors
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• Timing of millisecond pulsars in NGC\,6752 -- III. On the presence of non-luminous matter in the cluster's core
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• The Dynamical Implications of Multiple Stellar Formation Events in Galactic Globular Clusters
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• One of Everything: The Breakthrough Listen Exotica Catalog
• Detection of a white dwarf orbiting a Carbon-Oxygen depleted blue straggler in 47 Tucanae
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• Exotic populations in Globular Clusters: Blue Stragglers as tracers of the internal dynamical evolution of stellar systems
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