Space Velocities of Southern Globular Clusters. V. A Low Galactic Latitude Sample

Abstract

We have measured the absolute proper motions of globular clusters NGC 2808, 3201, 4372, 4833, 5927 and 5986. The proper motions are on the Hipparcos system and they are the first determinations ever made for these low Galactic latitude clusters. The proper motion uncertainties range from 0.3 to 0.5 mas/yr. The inferred orbits indicate that 1) the single metal rich cluster in our sample, NGC 5927, dynamically belongs to the thick disk, 2) the remaining metal poor clusters have rather low-energy orbits of high eccentricity; among these, there appear to be two "pairs" of dynamically associated clusters, 3) the most energetic cluster in our sample, NGC 3201 is on a highly retrograde orbit -- which had already been surmised from its radial velocity alone -- with an apocentric distance of 22 kpc, and 4) none of the metal poor clusters appear to be associated with the recently detected SDSS streams, or with the Monoceros structure. These are the first results of the Southern Proper-Motion Program (SPM) where the second-epoch observations are taken with the CCD camera system recently installed on the double astrograph at El Leoncito, Argentina.

To appear in AJ 134, 195

References in corpus (8)

• Detection of a 63 Degree Cold Stellar Stream in the Sloan Digital Sky Survey
• An Orphan in the "Field of Streams"
• Detection of a 60 Degree-Long Dwarf Galaxy Debris Stream
• The exotic chemical composition of the Sagittarius dwarf Spheroidal galaxy
• NGC 6441: another indication for a very high helium content in Globular Cluster stars
• The orbits of 48 globular clusters in a Milky-Way-Like Barred Galaxy
• The Chemical Evolution of Helium in Globular Clusters: Implications for the Self-Pollution Scenario
• The chemical evolution of Omega Centauri's progenitor system

Cited by in corpus (22)

• The stellar halo of the Galaxy
• Tombaugh 2: The First Open Cluster with a Significant Abundance Spread or Embedded in a Cold Stellar Stream?
• On the distance of the globular cluster M4 (NGC 6121) using RR Lyrae stars: I. optical and near-infrared Period-Luminosity and Period-Wesenheit relations
• Globular clusters in the outer halo of M31: the survey
• Fashionably Late? Building up the Milky Way's Inner Halo
• Tails and streams around the Galactic globular clusters NGC1851, NGC1904, NGC2298 and NGC2808
• The Effect of Orbital Eccentricity on the Dynamical Evolution of Star Clusters
• Six New Galactic Orbits of Globular Clusters in a Milky-Way-Like Galaxy
• The Effects of Orbital Inclination on the Scale Size and Evolution of Tidally Filling Star Clusters
• A study of rotating globular clusters - the case of the old, metal-poor globular cluster NGC 4372
• Detailed Abundances of 15 Stars in the Metal-Poor Globular Cluster NGC 4833
• The environment of formation as a second parameter for globular cluster classification
• Quantifying the Universality of the Stellar Initial Mass Function in Old Star Clusters
• Chemical Complexity in the Eu-enhanced Monometallic Globular Cluster NGC 5986
• A Spitzer search for cold dust within globular clusters
• Chemical Study of the Metal-rich Globular Cluster NGC 5927
• The Gaia-ESO Survey: Detailed Abundances in the Metal-poor Globular Cluster NGC 4372
• A proper motions study of the globular cluster NGC 3201
• A ground-based proper motion study of twelve nearby Globular Clusters
• Galactic Orbits of Globular Clusters in the Region of the Galactic Bulge
• Evolution of star clusters on eccentric orbits: semi-analytical approach
• Local Group Proper Motion Dynamics