[IAUC] CBET 3066: 20120324 : SUPERNOVA 2012bh IN UGC 7228

[quai en eps.harvard.edu]

                                                  Electronic Telegram No. 3066
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


SUPERNOVA 2012bh IN UGC 7228
     R. Chornock, G. H. Marion, and M. Calkins, Harvard-Smithsonian Center for
Astrophysics (CfA); R. Kotak, L. Magill, S. J. Smartt, K. Smith, and M. Fraser,
Queen's University, Belfast; C. Leibler, R. J. Foley, E. Berger, R. P.
Kirshner, G. Narayan, A. M. Soderberg, and C. Stubbs, CfA; A. Rest, Space
Telescope Science Institute; M. Huber and J. Tonry, Institute for Astronomy
(IfA), University of Hawaii; A. Riess, Johns Hopkins University; W. M. Wood-
Vasey, University of Pittsburgh; E. Magnier, K. Chambers, N. Kaiser, J. Morgan,
W. Burgett, J. Heasley, W. Sweeney, C. Waters, and H. Flewelling (IfA); and
P. A. Price, Princeton University, report the early discovery and
spectroscopic confirmation of a low-redshift type-Ia supernova (preliminary
designation PS1-12rg) in the galaxy UGC 7228 (cz = 7568 km/s; Falco et al.
1999, PASP 111, 438) by the Pan-STARRS1 Medium Deep Survey.  The object was
first detected on Mar. 11.50 UT at R.A. = 12h13m37s.309, Decl. = +46d29'00".48
(equinox 2000.0) with an approximate magnitude of z_P1 = 22.8 (AB); it rose to
mag i_P1 = 16.99 by Mar. 21.47.  A spectrum (range 480-940 nm), obtained on
Mar. 15 using the Gran Telescopio Canarias (+ OSIRIS + R300R grism), shows
2012bh to be a young, normal type-Ia supernova.  An additional spectrum
(range 350-740 nm) was obtained on Mar. 23 with the 1.5-m telescope at the
Fred L. Whipple Observatory on Mount Hopkins.  Cross-correlation of the Mar.
23 spectrum with a library of supernova spectral templates using the SNID code
of Blondin and Tonry (2007, Ap.J. 666, 1024) gives a best-fit age of about a
week before maximum light.  The velocity of the absorption minimum of Si II
635.5-nm is 10800 km/s.  This discovery was made possible by the PS1 system
operated by the PS1 Science Consortium and its member institutions (see URL
http://www.ps1sc.org/PS1_System_IAU.shtml).  The authors thank the telescope
operators of the PS1, GTC, and FLWO telescopes for their support.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2012 CBAT
2012 March 24                    (CBET 3066)              Daniel W. E. Green