Globular clusters as a probe for Weyl Conformal Gravity

Abstract

Eventual flattening of velocity dispersion profiles of some galactic globular clusters in the Milky Way cannot be explained in the framework of Newtonian gravity and hence in general theory of relativity in the weak field limit, without resorting to the occurrence of tidal effects. We explore the possibility of explaining such deviation from expected Keplerian fall-off in dispersion profiles within the context of Weyl conformal gravity. We choose a set of 20 globular clusters for which recent kinematic measurements are available. We model the globular clusters with approximate Hernquist mass profiles and choose a constant mass-to-light ratio throughout the cluster as the only free parameter in the model. Our analysis finds reasonable Weyl gravity fits to the observed dispersion profiles, exhibiting both Keplerian decline and eventual flattening, with acceptable mass-to-light ratios. We further recover a Tully-Fisher like scaling relation in globular clusters through Weyl gravity.

arXiv comment11 pages, 8 figures, Accepted for publication in MNRAS, to appear in the given DOI

References in corpus (36)

• The Cosmological Constant and Dark Energy
• Particle Dark Matter: Evidence, Candidates and Constraints
• PARSEC: stellar tracks and isochrones with the PAdova and TRieste Stellar Evolution Code
• A direct empirical proof of the existence of dark matter
• Resolved Massive Star Clusters in the Milky Way and its Satellites: Brightness Profiles and a Catalogue of Fundamental Parameters
• A catalogue of masses, structural parameters and velocity dispersion profiles of 112 Milky Way globular clusters
• Mean proper motions, space orbits and velocity dispersion profiles of Galactic globular clusters derived from Gaia DR2 data
• Alternatives to Dark Matter and Dark Energy
• No-ghost theorem for the fourth-order derivative Pais-Uhlenbeck oscillator model
• 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
• Fitting galactic rotation curves with conformal gravity and a global quadratic potential
• Impact of a global quadratic potential on galactic rotation curves
• Are galactic rotation curves really flat?
• Hubble Space Telescope proper motion (HSTPROMO) catalogs of Galactic globular clusters. II. Kinematic profiles and maps
• The internal rotation of globular clusters revealed by Gaia DR2
• Constraints on the Global Mass-to-Light Ratios and Extent of Dark Matter Halos in Globular Clusters and Dwarf Spheroidals
• Peculiarities in Velocity Dispersion and Surface Density Profiles of Star Clusters
• Testing modified gravity with globular cluster velocity dispersions
• Halo globular clusters observed with AAOmega: dark matter content, metallicity and tidal heating
• Fitting dwarf galaxy rotation curves with conformal gravity
• Dissolution is the solution: on the reduced mass-to-light ratios of Galactic globular clusters
• Conformal Weyl gravity and perihelion precession
• Testing Newtonian gravity with distant globular clusters: NGC1851 and NGC1904
• Using globular clusters to test gravity in the weak acceleration regime
• Testing fundamental physics with distant star clusters: theoretical models for pressure-supported stellar systems
• Schwarzschild limit of conformal gravity in the presence of macroscopic scalar fields
• Using globular clusters to test gravity in the weak acceleration regime: NGC 7099
• Flattened velocity dispersion profiles in Globular Clusters: Newtonian tides or modified gravity?
• The Global Kinematics of the Globular Cluster M92
• The Gaia-ESO Survey: Dynamical models of flattened, rotating globular clusters
• Distant star clusters of the Milky Way in MOND
• X-ray clusters of galaxies in conformal gravity
• Strong lensing as a test for Conformal Weyl Gravity
• Testing Weyl Gravity at Galactic and Extra-galactic Scales
• Application of three-body stability to globular clusters: I. The stability radius

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