A Caltech Library Service

Dynamical Correlations for Globular Clusters in M31

Djorgovski, S. G. and Gal, R. R. and McCarthy, J. K. and Cohen, J. G. and de Carvalho, R. R. and Meylan, G. and Bendinelli, O. and Parmeggiani, G. (1997) Dynamical Correlations for Globular Clusters in M31. Astrophysical Journal, 474 (1). L19-L22. ISSN 0004-637X. doi:10.1086/310423.

[img] PDF - Published Version
See Usage Policy.


Use this Persistent URL to link to this item:


We present internal velocity dispersion measurements for a set of 21 globular clusters in the Andromeda galaxy (M31). We combine them with structural and photometric cluster parameters measured earlier with the Hubble Space Telescope and from the ground to explore correlations of cluster properties and to compare them with the equivalent correlations for the Galactic globular clusters. We find that the M31 globulars follow the same correlations between velocity dispersion and luminosity, central, and average surface brightness, as do their Galactic counterparts. This suggests a common physical origin for these correlations. They may be produced by the same astrophysical conditions and processes operating at the epoch of globular cluster formation in both galaxies. The very existence of these excellent correlations, and their quantitative form as scaling laws, represent challenges and constraints for theories of globular cluster formation. Preliminary estimates of the cluster M/L ratios show correlations with the cluster metallicity, in the sense of more metal-rich clusters having lower M/L, particularly in the near-infrared. At a given metallicity, there is no detectable systematic difference between the M31 globulars and their Galactic counterparts, which suggests a great similarity of their stellar populations. The observed scatter around these trends is comparable to the expected errors, which implies a small intrinsic scatter and thus which leaves little room for possible variations in the cluster age or stellar IMF at a given metallicity.

Item Type:Article
Related URLs:
URLURL TypeDescription
Djorgovski, S. G.0000-0002-0603-3087
Cohen, J. G.0000-0002-8039-4673
de Carvalho, R. R.0000-0002-1283-3363
Additional Information:© 1997. The American Astronomical Society Received 1996 August 20; accepted 1996 October 16. Based in part on observations obtained at the W. M. Keck Observatory, which is operated jointly by the California Institute of Technology and the University of California. Based in part on observations obtained with the NASA/ESA Hubble Space Telescope, operated by the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS 5-26555. We acknowledge expert help of the staff of the W. M. Keck Observatory, particularly T. Chelminiak, and the work of many collaborators on the HST M31 GC team, especially F. Fusi Pecci. G1 data were kindly communicated by R. M. Rich and D. Neill. This work was supported in part by the NSF PYI award AST-9157412 to S. G. D.; NASA grants GO-2583, 3726, and 5420 from STScI; and an NSF graduate fellowship to R. R. G.
Funding AgencyGrant Number
NASANAS 5-26555
NSF Graduate Research FellowshipUNSPECIFIED
Subject Keywords:galaxies: individual: M31 — galaxies: star clusters — globular clusters: general
Issue or Number:1
Record Number:CaltechAUTHORS:20190603-153225522
Persistent URL:
Official Citation:S. G. Djorgovski et al 1997 ApJ 474 L19
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:96092
Deposited By: George Porter
Deposited On:04 Jun 2019 21:47
Last Modified:16 Nov 2021 17:17

Repository Staff Only: item control page