[IAUC] CBET 2390: 20100724 : SUPERNOVAE 2010gc, 2010gh, AND 2010gp

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                                                  Electronic Telegram No. 2390
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.
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SUPERNOVAE 2010gc, 2010gh, AND 2010gp
     G. Folatelli and C. Gutierrez, Universidad de Chile; and G. Pignata,
Universidad Andres Bello, on behalf of the Millennium Center for Supernova
Science, report that they obtained optical spectrograms (range 354-886 nm) of
2010gc (cf. CBET 2367), 2010gh (cf. CBET 2372), and 2010gp (cf. CBET 2388) on
July 23.0 UT with the SOAR telescope (+ Goodman HTS).  SN 2010gc is a type-Ia
supernova between ten days and two weeks after maximum light.  Cross-
correlation with a library of supernova spectra using the "Supernova
Identification" code (SNID; Blondin and Tonry 2007, Ap.J. 666, 1024) provides
an estimated redshift of 0.06 and the best match to SN 1998bu at 12 days after
maximum; adopting that redshift, the absorption minimum of the Si II 635.5-nm
line for 2010gc appears blueshifted by about 9000 km/s.
     SN 2010gh is a type-II-P supernova between 20 and 30 days after the
explosion.  SNID provides a good match with the spectrum of SN 2004et at 28
days after the explosion.  Assuming a recession velocity of 4714 km/s for
the host galaxy (IC 4523; Peterson 1986, PASP 98, 1273), H-alpha is measured
to be blueshifted by roughly 8000 km/s.
     SN 2010gp is a type-Ia supernova with high expansion velocity around
maximum light.  SNID provides good matches to SN 2002bo and to SN 1981B just
before maximum light.  Adoping the recession velocity of 7339 km/s for the
host galaxy (NGC 6240; Downes et al. 1993, Ap.J. 414, L13), the Si II 635.5-nm
line apears blueshifted by about 14000 km/s.


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                         (C) Copyright 2010 CBAT
2010 July 24                     (CBET 2390)              Daniel W. E. Green