THE CIRCUMSTELLAR MEDIUM OF THE PECULIAR SUPERNOVA SN1997AB

We report the detection of the slow-moving wind into which the compact supernova remnant SN 1997ab is expanding. Echelle spectroscopy provid es clear evidence for a well-resolved narrow (full width at zero inten sity, FWZI similar to 180 km s(-1)) P Cygni profile, both in Her and H P, superimposed on the broad emission Lines of this compact supernova remnant. From theoretical arguments we know that the broad and strong emission lines imply a circumstellar density (n greater than or equal to 10(7) cm(-3)). This, together with our detection, implies a massive and slow Stellar wind experienced by the progenitor star shortly prio r to the explosion.