SCYON Abstract

Received on September 6 2002

Structural Parameters and Dynamical Masses for Globular Clusters in M33

AuthorsS.S. Larsen (1), J.P. Brodie (1), A. Sarajedini (2), J.P. Huchra (3)
Affiliation(1) UCO / Lick Observatory,
(2) Dept of Astronomy, Univ. of Florida,
(3) Harvard-Smithsonian CfA
Accepted byAstronomical Journal
Contactsoeren@ucolick.org
URLhttp://xxx.lanl.gov/abs/astro-ph/0208169
Links

Abstract

Using high-dispersion spectra from the HIRES echelle spectrograph on the Keck I telescope, we have measured velocity dispersions for 4 globular clusters in M33. Combining the velocity dispersions with integrated photometry and structural parameters derived from King-Michie model fits to WFPC2 images, we obtain mass-to-light ratios for the clusters. The mean value is M/L(V) = 1.53 ± 0.18, very similar to the M/L(V) of Milky Way and M31 GCs. The M33 clusters also fit very well onto the fundamental plane and binding energy - luminosity relations derived for Milky Way GCs. Dynamically and structurally, the four M33 clusters studied here appear virtually identical to Milky Way and M31 GCs.