TYPE-IA SUPERNOVA SN-1995D IN NGC-2962 - OPTICAL V-BAND, R-BAND, AND I-BAND PHOTOMETRY AND SPECTRA

Optical light curves in the V, R, and I bands, starting 10 days before the maximum light, and the optical spectra near to the V maximum phas e of supernova SN 1995D in NGC 2962 are presented. The spectra taken n ear to the optical maximum are similar to the prototypical type-Ia sup ernova SN 1981B, and show no trace of the interstellar Nar D Line. The expansion velocity at the maximum phase was 10000 +/- 200 km s(-1). T he supernova reached maximum light in the I band about four days earli er than in the V band. A distinct secondary peak is observed in the I band about 30 days after the V maximum. This secondary peak occurred a bout one week delayed from the published template light curve. A clear shoulder is detected in the R band light curve corresponding to the s econdary peak in the I band. The initial rate of decline is slow [Delt a m(15)(V) = 0.66 mag], and it is suggested that the supernova belongs to a group of the intrinsically brightest type-Ia supernovae. From th e initial declining rate in the V band, we estimated the absolute magn itude M(V) to be -18.8 +/- 0.3 mag, and the distance modulus of the pa rent galaxy (NGC 2962) to be 32.2 +/- 0.3 mag.