Supernovae 2008ga and 2008gb
Abstract
P. Garnavich, K. Mohrig, and N. Mancinelli, University of Notre Dame; and B. Dilday, Rutgers University, report that spectra (range 350-900 nm; resolution 0.67 nm) of 2008gb were obtained with the 3.5-m Apache Point Observatory telescope (+ Dual Imaging Spectrograph) on Oct. 7.5 UT. The spectra show the supernova to be of type Ia, a few days before maximum light. H_alpha emission from the host galaxy indicates a redshift of 0.037. The deep Si II absorption minimum shows a blue shift of 11400 km/s. The ratio of the 580-nm/615-nm line depths suggests a mildly-fast-declining light curve with a delta_m15(B) parameter (Garnavich et al. 2004, Ap.J. 613, 1120) of 1.3.
- Publication:
-
Central Bureau Electronic Telegrams
- Pub Date:
- October 2008
- Bibcode:
- 2008CBET.1530....2G