Galactic Globular Clusters: A new catalog of masses, structural parameters, velocity dispersion profiles, proper motions and space orbits

AbstractWe collected radial velocities of more than 50.000 individual stars in 156 Galactic globular clusters (GGC) and matched them with HST photometry and Gaia DR2 proper motions. This allowed us to derive the GGC’s mean proper motions and space velocities. By fitting a large set of N-body simulations to their velocity dispersion and surface density profiles, combined with new measurements of their internal radially dependent mass functions, we have determined their present-day masses and structural parameters, and for 144 GGCs their internal kinematics. We also derive the initial cluster masses by calculating the cluster orbits backwards in time applying suitable recipes to account for mass-loss and dynamical friction. The new fundamental parameters of GGCs are publicly available via an online database, which will regularly be updated.

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Mean proper motions, space orbits, and velocity dispersion profiles of Galactic globular clusters derived fromGaiaDR2 data

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/sty2997 ◽

2018 ◽

Vol 482 (4) ◽

pp. 5138-5155 ◽

Cited By ~ 119

Author(s):

H Baumgardt ◽

M Hilker ◽

A Sollima ◽

A Bellini

Keyword(s):

Globular Clusters ◽

Velocity Dispersion ◽

Proper Motions ◽

Galactic Globular Clusters

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STAR COUNT DENSITY PROFILES AND STRUCTURAL PARAMETERS OF 26 GALACTIC GLOBULAR CLUSTERS

The Astrophysical Journal ◽

10.1088/0004-637x/774/2/151 ◽

2013 ◽

Vol 774 (2) ◽

pp. 151 ◽

Cited By ~ 68

Author(s):

P. Miocchi ◽

B. Lanzoni ◽

F. R. Ferraro ◽

E. Dalessandro ◽

E. Vesperini ◽

...

Keyword(s):

Globular Clusters ◽

Structural Parameters ◽

Density Profiles ◽

Count Density ◽

Star Count ◽

Galactic Globular Clusters

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MOCCA Survey Database: Extra Galactic Globular Clusters. I. Method and first results

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa4027 ◽

2021 ◽

Author(s):

A Leveque ◽

M Giersz ◽

M Paolillo

Keyword(s):

Globular Clusters ◽

Surface Brightness ◽

Velocity Dispersion ◽

Structural Parameters ◽

Dynamical Evolution ◽

Central Surface ◽

First Results ◽

Preliminary Study ◽

Galactic Globular Clusters ◽

Gaia Dr2

Abstract Over the last few decades, exhaustive surveys of extra Galactic globular clusters (EGGCs) have become feasible. Only recently, limited kinematical information of globular clusters (GCs) were available through Gaia DR2 spectroscopy and also proper motions. On the other hand, simulations of GCs can provide detailed information about the dynamical evolution of the system. We present a preliminary study of EGGCs- properties for different dynamical evolutionary stages. We apply this study to 12 Gyr-old GCs simulated as part of the MOCCA Survey Database. Mimicking observational limits, we consider only a subssample of the models in the database, showing that it is possible to represent observed Milky Way GCs. In order to distinguish between different dynamical states of EGGCs, at least three structural parameters are necessary. The best distinction is achieved by considering the central parameters, those being observational core radius, central surface brightness, ratio between central and half-mass velocity dispersion, or similarly considering the central color, the central V magnitude and the ratio between central and half-mass radius velocity dispersion, although such properties could be prohibitive with current technologies. A similar but less solid result is obtained considering the average properties at the half-light radius, perhaps accessible presently in the Local Group. Additionally, we mention that the color spread in EGGCs due to internal dynamical models, at fixed metallcity, could be just as important due to the spread in metallicity.

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Testing for Dark Matter in the Outskirts of Globular Clusters

The Astrophysical Journal ◽

10.3847/1538-4357/ac289f ◽

2021 ◽

Vol 922 (2) ◽

pp. 104

Author(s):

Raymond G. Carlberg ◽

Carl J. Grillmair

Keyword(s):

Dark Matter ◽

Globular Clusters ◽

High Probability ◽

Velocity Dispersion ◽

High Redshift ◽

Dark Matter Halo ◽

The Sun ◽

Proper Motions ◽

Preliminary Results ◽

Galactic Background

Abstract The proper motions of stars in the outskirts of globular clusters are used to estimate cluster velocity dispersion profiles as far as possible within their tidal radii. We use individual color–magnitude diagrams to select high-probability cluster stars for 25 metal-poor globular clusters within 20 kpc of the Sun, 19 of which have substantial numbers of stars at large radii. Of the 19, 11 clusters have a falling velocity dispersion in the 3–6 half-mass radii range, 6 are flat, and 2 plausibly have a rising velocity dispersion. The profiles are all in the range expected from simulated clusters that started at high redshift in a zoom-in cosmological simulation. The 11 clusters with falling velocity dispersion profiles are consistent with no dark matter above the Galactic background. The six clusters with approximately flat velocity dispersion profiles could have local dark matter, but are ambiguous. The two clusters with rising velocity dispersion profiles are consistent with a remnant local dark matter halo, but need membership confirmation and detailed orbital modeling to further test these preliminary results.

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Orbits of Galactic Globular Clusters from Schmidt Plate Astrometry

Symposium - International Astronomical Union ◽

10.1017/s0074180900047847 ◽

1994 ◽

Vol 161 ◽

pp. 453-459 ◽

Cited By ~ 1

Author(s):

M. Odenkirchen ◽

R.-D. Scholz ◽

M.J. Irwin

Keyword(s):

Globular Clusters ◽

Proper Motions ◽

Mass Model ◽

Orbital Parameters ◽

The Galaxy ◽

Galactic Globular Clusters

We present results from orbit integrations for the globular clusters M 3 and M 92. Absolute proper motions recently measured from Tautenburg Schmidt plates and a three-component mass model for the Galaxy have been used to derive the galactic orbits of these clusters. Orbital parameters and the influence of observational uncertainties on the determination of the orbits are discussed.

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G2C2 – III. Structural parameters for Galactic globular clusters in SDSS passbands

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stv850 ◽

2015 ◽

Vol 450 (3) ◽

pp. 2692-2707 ◽

Cited By ~ 7

Author(s):

Joachim Vanderbeke ◽

Roberto De Propris ◽

Sven De Rijcke ◽

Maarten Baes ◽

Michael J. West ◽

...

Keyword(s):

Globular Clusters ◽

Structural Parameters ◽

Galactic Globular Clusters

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Internal kinematics of multiple stellar populations in globular clusters

Proceedings of the International Astronomical Union ◽

10.1017/s1743921319006525 ◽

2019 ◽

Vol 14 (S351) ◽

pp. 324-328

Author(s):

Mattia Libralato

Keyword(s):

High Precision ◽

Globular Clusters ◽

Hubble Space Telescope ◽

Stellar Populations ◽

Stellar Systems ◽

Proper Motions ◽

Space Telescope ◽

Formation And Evolution ◽

Galactic Globular Clusters ◽

Shed Light

AbstractSpectroscopy and photometry have revealed existence, complexity and properties of the multiple stellar populations (mPOPs) hosted in Galactic globular clusters. However, the conundrum of the formation and evolution of mPOPs is far from being completely exploited: the available pieces of information seem not enough to shed light on these topics. Astrometry, and in particular high-precision proper motions, can provide us the sought-after answers about how mPOPs formed and have evolved in these ancient stellar systems. In the following, I present a brief overview of the observational results on the internal kinematics of the mPOPs in some GCs thanks to Hubble Space Telescope high-precision proper motions.

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Kinematics of Galactic Globular Clusters from Schmidt-Plate Astrometry

Symposium - International Astronomical Union ◽

10.1017/s0074180900109222 ◽

1995 ◽

Vol 164 ◽

pp. 405-405 ◽

Cited By ~ 1

Author(s):

R.-D. Scholz ◽

S. Hirte ◽

M.J. Irwin ◽

M. Odenkirchen

Keyword(s):

Radial Velocity ◽

Proper Motion ◽

Globular Clusters ◽

Proper Motions ◽

Large Numbers ◽

Solar Motion ◽

The Galaxy ◽

Ursa Minor ◽

Galactic Globular Clusters

From measurements of Tautenburg Schmidt plates with the APM facility in Cambridge we obtained absolute proper motions of the Galactic globular clusters M 3 and M 92 directly with respect to large numbers of background galaxies (Scholz et al. 1993, 1994). We have extended our work to the dSphs in Draco and Ursa Minor (Scholz & Irwin 1994) and to other Galactic globular clusters using Tautenburg, Palomar and UK Schmidt plates. Combining our absolute proper motion of a cluster with its known radial velocity and distance (using common parameters of the solar motion) we derive the cluster orbit in the Galaxy (cf. Odenkirchen & Brosche 1992).

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