[IAUC] CBET 2453: 20100912 : SUPERNOVAE 2010hd, 2010hg, AND 2010hj

[quai en eps.harvard.edu]

                                                  Electronic Telegram No. 2453
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
CBAT Director:  Daniel W. E. Green; Hoffman Lab 209; Harvard University;
 20 Oxford St.; Cambridge, MA  02138; U.S.A.
e-mail:  cbatiau en eps.harvard.edu (alternate cbat en iau.org)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network


SUPERNOVAE 2010hd, 2010hg, AND 2010hj
     J. L. Prieto, Carnegie Observatories; and J. Fuentes, Las Campanas
Observatory, report that they obtained optical spectra (range 380-920 nm;
resolution 0.7 nm) of 2010hd (cf. CBET 2429), 2010hg (cf. CBET 2434), and
2010hj (cf. CBET 2438) on Sept. 10 UT with WFCCD mounted on the du Pont 2.5-m
telescope at Las Campanas Observatory.  The SNID cross-correlation software
(Blondin and Tonry 2007, Ap.J. 666, 1024) was used to aid identification and
age/redshift estimation.  The spectrum of 2010hd resembles that of the
type-IIn supernova 1998S at 72 days after discovery (see Fassia et al. 2001,
MNRAS 325, 907); it is dominated by a strong, intermediate width (FWHM about
5600 km/s) H-alpha line in emission, He I and Fe II lines in absorption, and
the Ca II near-infrared triplet in emission.  SN 2010hg is a type-Ia supernova
a couple days before maximum light; after correcting for the recession
velocity of the host galaxy, NGC 3001 (2464 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) profile is measured to be 10000 km/s.  The spectrum of 2010hj
is that of a normal type-Ia supernova at approximately two months after
maximum light; the redshift obtained by SNID from the supernova spectrum is z
= 0.030 +/- 0.005.

     Additional unfiltered CCD magnitudes for 2010hg from L. A. G. Monard in
Pretoria:  Sept. 4.139 UT, 14.4; 5.138, 14.2; 6.140, 14.1; 7.136, 14.0;
8.138, 14.0; 9.137, 13.9.


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                         (C) Copyright 2010 CBAT
2010 September 12                (CBET 2453)              Daniel W. E. Green