N. Morrell, Las Campanas Observatory; and G. Pignata, Universidad de Chile, on behalf of the Carnegie Supernova Project, report that a spectrogram (range 380-920 nm) of 2007pl (cf. CBET 1130), obtained on Nov. 11.34 UT with the du Pont 2.5-m telescope (+ WFCCD) at Las Campanas Observatory, shows this to be a type-Ia supernova a couple of weeks after maximum light. Adopting the NED recession velocity of 8647 km/s for the host galaxy (from de Vaucouleurs et al. 1991, Third Ref. Cat. of Bright Galaxies) the 'superfit' spectrum-comparison code (Howell et al. 2005, Ap.J. 634, 1190) provides the best match to SN 1999aw at fifteen days after maximum. The spectrum shows evidence of absorption in the host galaxy due to Na I D (EW about 1.5). Considering the recession velocity given above, the minimum absorption of the Si II 635.5-nm line indicates an expansion velocity of about 11000 km/s.
Central Bureau Electronic Telegrams
- Pub Date:
- November 2007