The Morphology of Star Clusters in the SMC
Abstract
The projected ellipticities of 34 populous SMC star clusters have been derived by means of PDS 1010A scans and a computer interactive method of reduction implemented by the authors on an Apollo 570 workstation. A pair of J and R plates taken with the 1.2 m U.K. Schmidt telescope in Australia were used. Radial ellipticity variations within individual globular clusters seem to be a common phenomenon for the SMC clusters similar to that observed in the LMC clusters where the innerparts are more elliptical than the outer ones in 95% of the cases. The derived ellipticities which correspond to the innermost part of the cluster at radial distances near to half mass radii have been found to be statistically more elliptical than those of the LMC, known to be more elliptical than those of our galaxy. The dynamical masses of the clusters seem to correlate with ellipticities supporting the hypothesis that, either the gravitational field of the parent galaxy being a dominant factor affect slower the shape of the high mass clusters and/or the most massive clusters, being dynamically younger, retain their original shape.
- Publication:
-
The Astronomical Journal
- Pub Date:
- August 1990
- DOI:
- 10.1086/115527
- Bibcode:
- 1990AJ....100..425K
- Keywords:
-
- Galactic Structure;
- Globular Clusters;
- Gravitational Fields;
- Magellanic Clouds;
- Star Clusters;
- Astronomical Photography;
- Image Processing;
- Schmidt Telescopes;
- Stellar Evolution;
- Astrophysics;
- GALAXIES: MAGELLANIC CLOUDS;
- GALAXIES: STELLAR CONTENT