We report the detection of the slow expanding wind into which
the compact supernova remnant SN 1997ab is expanding.
Echelle spectroscopy provides
clear evidence for a well
resolved and narrow (FWHM~45 km s-1) P-Cygni profile, both in
H_alpha and
H_beta, superimposed
on the broad (FWHM ~ 2000 km s-1) compact supernova remnant emission
lines.
From theorical arguments we know that the broad and strong emission lines imply a circumstellar density (n >= 107cm-3). This, together with our detection, implies a massive and slow stellar wind experienced by the progenitor star a few years prior to explosion. We also postulate our observing strategy as being ideal to derive the properties of the circumstellar matter, and enable the inference of the final evolutionary stages of the progenitor star.