Proper motions and dynamics of the Milky Way globular cluster system fromGaiaDR2

By Eugene O. Vasiliev. Monthly notices of the Royal Astronomical Society, 2018

197 citations recorded by the source corpus.

We use Gaia Data Release 2 to determine the mean proper motions for 150 Milky Way globular clusters (almost the entire known population), with a typical uncertainty of 0.05 mas/yr limited mainly by systematic errors. Combining them with distance and line-of-sight velocity measurements from the literature, we analyze the distribution of globular clusters in the 6d phase space, using both position/velocity and action/angle coordinates. The population of clusters in the central 10 kpc has a mean rotational velocity reaching 50-80 km/s, and a nearly isotropic velocity dispersion 100-120 km/s, while in the outer galaxy the cluster orbits are strongly radially anisotropic. We confirm a concentration of clusters at high radial action in the outer region of the Galaxy. Finally, we explore a range of equilibrium distribution function-based models for the entire globular cluster system, and the information they provide about the potential of the Milky Way. The dynamics of clusters is best described by models with the circular velocity between 10 and 50 kpc staying in the range 210-240 km/s.

Subfields: Astronomy and Astrophysics

View Paper: https://www.semanticscholar.org/paper/272580d370225190861bb435f6e195033dfbfcf6

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Citations in the corpus

The total mass of the Large Magellanic Cloud from its perturbation on the Orphan stream (2018, methodology): “…which attempts to precisely measure the properties of the Milky Way by studying tracers orbiting our Galaxy, e.g. equilibrium modelling of GCs (e.g. Watkins, Evans & An 2010; Vasiliev 2019), the stellar halo (Xue et al. 2008; Deason et al. 2012), or hypervelocity stars (Gnedin et al. 2005).”
Evidence from the H3 Survey That the Stellar Halo Is Entirely Comprised of Substructure (2020, methodology): “In the third panel, we depict a summary of actions in the form of (Jz–JR)/Jtot versus Jf/Jtot following Binney & Tremaine (2008) and Vasiliev (2019).”
The GALAH+ survey: Third data release (2020, background): “However, this projection also allows the identification of accreted stars and stars of streams (see e.g. Vasiliev 2019; Myeong et al. 2019; Monty et al. 2020).”
Gaia EDR3 view on galactic globular clusters (2021, methodology): “While the improvements in precision for mean PM with respect to studies based on DR2 (Gaia Collaboration 2018, Baumgardt et al. 2019, Vasiliev 2019b) is substantial, the precision of the phase-space coordinates is typically lim- ited by distance uncertainties, so has not improved as much.”
A Nearby Repeating Fast Radio Burst in the Direction of M81 (2021, background): “…a Milky Way satellite galaxy (Kaisina et al. 2019; Karachentsev & Kaisina 2019) or a globular cluster (Harris 2010; Gaia Collaboration et al. 2018; Vasiliev 2019), but no such cataloged source exists within or near (within an ∼10° radius circular sky area) the FRB localization region (Contenta et…”
Origin of the system of globular clusters in the Milky Way (2019, methodology): “We used the AGAMA package (Vasiliev 2019b) with the McMillan (2017) potential to compute GCs orbital parameters like the apocenter (apo), maximum height from the disc (Zmax), and eccentricity (ecc).”
Evidence for two early accretion events that built the Milky Way stellar halo (2019, background): “5 shows the Milky Way GCs from Vasiliev (2019), together with the substructures found by Myeong et al. (2018b), in the plot of scaled action.”
The hidden giant: discovery of an enormous Galactic dwarf satellite in Gaia DR2 (2018, methodology): “8 presents the orbit of Ant 2 generated using the MWPotential2014 (Bovy 2015) with the MW’s halo mass increased from 0.8 × 1012 to 0.9 × 1012 M (see e.g. Vasiliev 2019, for recent mass estimates).”