[IAUC] CBET 3004: 20120129 : SUPERNOVA 2012T IN NGC 5421 = PSN J14014169+3349339

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                                                  Electronic Telegram No. 3004
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 2012T IN NGC 5421 = PSN J14014169+3349339
     A. Kroes, J. Newton, and T. Puckett report the discovery of an apparent
supernova (mag 17.4) on an unfiltered CCD image (limiting mag 18.9) taken with
a 0.40-m reflector at Portal, AZ, U.S.A., on Jan. 26.472 UT in the course of
the Puckett Observatory Supernova Search.  The new object is located at R.A. =
14h01m41s.69, Decl. = +33o49'33".9  (equinox 2000.0), which is 3".5 east and
3".4 south of the center of NGC 5421.  The variable was designated PSN
J14014169+3349339 when it was posted at the Central Bureau's TOCP webpage and
is here designated SN 201TTT based on the spectroscopic confirmation reported
below.  The discovery image has been posted at the following website URL:
http://www.possdata.com/PSNJ14014169+3349339.pg.  Additional CCD magnitudes
for 2012T:  2011 May 2, 19.6 (Puckett); 2012 Jan. 27.461, 17.8 (Joseph
Brimacombe, Cairns, Australia; luminance filter; position end figures 41s.67,
33".9; image posted at http://www.flickr.com/photos/43846774@N02/6773335531/).

     G. H. Marion, Harvard-Smithsonian Center for Astrophysics (CfA), on
behalf of the CfA Supernova Group, report that a spectrum (range 340-740 nm)
of PSN J14014169+3349339 = 2012T was obtained on Jan. 27 UT by J. Irwin with
the F. L. Whipple Observatory 1.5-m telescope (+ FAST).  Cross-correlation
with a library of supernova spectra using the "Supernova Identification" code
(SNID; Blondin and Tonry 2007, Ap.J. 666, 1024) shows that 2012T is a type-Ia
supernova before maximum light.  A good fit is found to the template of the
1991bg-like supernova 1999by at four days before maximum.  The velocities of
Si II at 635.5 and 597.2 nm are 10200 and 9800 km/s, respectively, assuming a
redshift of z = 0.026 that was measured from host-galaxy emission lines.  The
R(Si II) line-depth ratio (Nugent et al. 1995, Ap.J. 455, L147) is about 0.68,
which is consistent with 1991bg-like type-Ia supernovae.  The most recently
reported brightness (mag 17.4 on Jan. 26 by Puckett) is about 1.5 magnitudes
below the expected brightness for a normal type-Ia supernova at maximum.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
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                         (C) Copyright 2012 CBAT
2012 January 29                  (CBET 3004)              Daniel W. E. Green