FUNDAMENTAL PARAMETERS OF THE HIGHLY REDDENED YOUNG OPEN CLUSTERS WESTERLUND-1 AND WESTERLUND-2

We study the compact open clusters Westerlund 1 (BH 197) and Westerlun d 2. We present CCD integrated spectroscopy for both clusters, and CCD imaging in the V and I bands for the former one. So far, Westerlund 1 is possibly the most reddened open cluster studied in detail (A(nu) a pproximate to 13.0). It has an age of 8 +/- 3 Myr and a distance from the Sun of d. approximate to 1.0 +/- 0.4 kpc. I?br Westerlund 2 we der ive a visual absorption A(V) approximate to 5.0 mag, an age of 2 - 3 M yr, End d. = 5.7 +/- 0.3 kpc. From luminosity and structural arguments we conclude that Westerlund 1, although young and compact, it is a ma ssive cluster, in contrast to Westerlund 2.