2008CBET.1577....1F

G. Folatelli, F. Forster, and M. Stritzinger, on behalf of the Carnegie Supernova Project and Millennium Center for Supernova Studies collaboration, report that they obtained spectra (range 340-602 nm) of 2008gy (cf. CBET 1565) and 2008hg (cf. CBET 1571, 1573) with the New Technology Telescope (+ EFOSC2) at La Silla on Nov. 19.0-19.1 UT.

The spectrum of 2008gy shows it to be a type-Ia supernova, two to three weeks after maximum light. With the aid of the "Supernova Identification" code (SNID; Blondin and Tonry 2007, Ap.J. 666, 1024), a redshift of 0.029 is found for 2008gy. SNID provides the best match with the type-Ia supernova 1990N at 18 days past maximum. Adopting the redshift given above, the blend of the Ca II H and K lines is measured to be blueshifted by about 13400 km/s.

The spectrum of SN 2008hg is that of a young type-IIp supernova. SNID provides matches with spectra of the type-IIp supernovae 1999em and 2005cs, a few days after the explosion. Adopting a recession velocity of 5684 km/s for the host galaxy (IC 1720; Mathewson and Ford 1996, Ap.J. Suppl. 107, 97), an expansion velocity of 8200 km/s is derived from the absorption minimum of the H-beta line.