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Structural Parameters and Dynamical Masses for Globular Clusters in M33

S. S. Larsen·J. P. Brodie·A. Sarajedini·J. P. Huchra
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Abstract

Using high-dispersion spectra from the HIRES echelle spectrograph on the Keck I telescope, we measure 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/LV = 1.53 +/- 0.18, very similar to the M/LV of Milky Way and M31 globular clusters. 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.

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S. S. Larsen, J. P. Brodie, A. Sarajedini, J. P. Huchra. 2002-08-07. Structural Parameters and Dynamical Masses for Globular Clusters in M33. https://doi.org/10.1086/344110

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