STScI Preprint #1230

HST Study of the Stellar Populations around SN 1987A

Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by AURA, Inc. under NASA contract NAS 5-26555.

We present a short account of a study of the stellar populations around SN 1987A based on an analysis of multi-band HST-WFPC2 images. The effective temperature, radius and reddening of each star were determined by fitting the measured broad band magnitudes to the ones calculated with model atmospheres. In addition, all stars with H equivalent widths in excess of 8Å were identified. An inspection to the HR diagram reveals the presence of several generations of stars, with ages between 1 and 150 Myrs, superposed on a much older field population. The youngest stars in the field appear to be T Tau stars, characterized by strong H excesses. We conclude that SN 1987A is associated with a region in which star formation has been active over a long time interval and is still very active at present.

Status:

To appear in: the proceedings of the Workshop The Magellanic Clouds and Other Dwarf Galaxies, held 18-22 January 1998 in Bad Honnef, Germany

Affiliations:

¹)Space Telescope Science Institute, 3700 San Martin Drive Baltimore, MD 21218, USA
²)Scuola Normale Superiore, Pisa, Italy
³)On assignment from Astrophysics Division, Space Science Department of ESA
⁴)Osservatorio Astrofisico di Catania, Viale A. Doria 6, I-95125, Catania, Italia