[IAUC] CBET 2364: 20100711 : SUPERNOVAE 2010fz AND 2010ga

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                                                  Electronic Telegram No. 2364
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
CBAT Director:  Daniel W. E. Green; Room 209; Dept. of Earth and Planetary
 Sciences; Harvard University; 20 Oxford St.; Cambridge, MA  02138; U.S.A.
e-mail:  cbat en iau.org; cbatiau en eps.harvard.edu
URL http://www.cfa.harvard.edu/iau/cbat.html


SUPERNOVAE 2010fz AND 2010ga
     J. L. Prieto, Carnegie Observatories; N. Morrell and O. Duhalde, Las
Campanas Observatory; and L. A. G. Monard, Pretoria, South Africa, report
that they obtained optical spectra (range 380-920 nm; resolution 0.7nm) of
2010fz (cf. CBET 2361) and 2010ga (cf. CBET 2363) on July 11 UT with WFCCD
mounted on the du Pont 2.5-m telescope at Las Campanas Observatory.  The
spectrum of 2010fz shows characteristics of a young, reddened, type-Ia
supernova at 1-2 weeks before maximum.  After correcting for the recession
velocity of its host galaxy (NGC 2967) of 1892 km/s (H I Parkes All-Sky
Survey Final Catalog; Wong et al. 2006, MNRAS 371, 1855), a blueshift of the
Si II (rest 635.5 nm) line is measured to be 13000 km/s.  Strong Na I D
absorption is detected from the interstellar medium of our Galaxy (EW =
0.10 nm) and the host galaxy (EW = 0.13 nm), indicative of extinction in the
line-of-sight.
     SN 2010ga is a type-Ia supernova a few days after maximum light.  The
redshift of the host galaxy (2MASX J00344266+0954382) is measured to be z =
0.057 from the wavelength of H-alpha in emission (observed wavelength 694.1
nm).  Cross-correlation with a library of supernova spectra using SNID
(Blondin and Tonry 2007, Ap.J. 666, 1024) shows that 2010ga is most similar
to SN 1991T at 11 days after maximum light.  Other 1991T-like spectral
templates give good cross-correlation fits at a similar age.  The redshift
obtained by SNID from the cross-correlation, z = 0.056, is fully consistent
with the host-galaxy redshift.


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                         (C) Copyright 2010 CBAT
2010 July 11                     (CBET 2364)              Daniel W. E. Green