[IAUC] CBET 1246: 20080209 : SUPERNOVAE 2008Y AND 2008Z

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                                                  Electronic Telegram No. 1246
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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SUPERNOVAE 2008Y AND 2008Z
     S. Blondin, Harvard-Smithsonian Center for Astrophysics (CfA), on behalf
of the CfA Supernova Group, reports that spectra (range 350-740 nm) of 2008Y
(cf. CBET 1240) and 2008Z (cf. CBET 1243), obtained respectively on Feb. 9.41
and 9.31 UT by M. Calkins with the F. L. Whipple Observatory 1.5-m telescope
(+ FAST), show them both to be type-Ia supernovae.  Cross-correlation with a
library of supernova spectra using the "Supernova Identification" code (SNID;
Blondin and Tonry 2007, Ap.J. 666, 1024) indicates that 2008Y is most similar
to the type-Ia supernova 2005cf (cf. IAUC 8534) at 5 days past maximum light,
and that 2008Z is most similar to the type-Ia supernova 2003du (cf. IAUCs 8121,
8122) at 6 days before maximum.  Adopting a recession velocity of 20892 km/s
for the host galaxy of 2008Y (Sloan Digital Sky Survey Data Release 3), the
maximum absorption in the Si II line (rest 635.5 nm) is blueshifted by roughly
11600 km/s; narrow H_alpha emission is detected in the spectrum at the
redshift of the apparent host galaxy (SDSS J094315.36+361709.2; cz = 6293
km/s; SDSS Data Release 4).  Adopting this recession velocity for the host
galaxy of 2008Z, the maximum absorption in the Si II line is blueshifted by
roughly 12700 km/s.
     Further to CBET 1240, T. Puckett adds that SN 2008Y appears to be
associated with the spiral galaxy MCG +09-19-39 (= PGC 34650).


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                         (C) Copyright 2008 CBAT
2008 February 9                  (CBET 1246)              Daniel W. E. Green