[IAUC] CBET 3373: 20130107 : SUPERNOVA 2013B IN ESO 60-26 = PSN J09040080-7203248

[quai en eps.harvard.edu]

                                                  Electronic Telegram No. 3373
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 2013B IN ESO 60-26 = PSN J09040080-7203248
     Stuart Parker, Canterbury, New Zealand, reports the discovery of an
apparent supernova (red mag 17.2) on a 30-s unfiltered CCD image (limiting mag
18.5) taken by himself on Jan. 3.516 UT with a 30-cm Astro-Tech AT12RC
Ritchey-Chretien astrograph (+ ST10 camera) at his Parkdale Observatory in the
course of the Backyard Observatory Supernova Search (BOSS).  The new object is
located at R.A. = 9h04m00s.80, Decl. = -72d03'24".8 (equinox 2000.0; reference
stars from USNO-B and UCAC3 catalogues), which is 1" east and 9" south of the
nucleus of the galaxy IC 2532.  Nothing is visible at this position on
Digitized Sky Survey red and infrared images (limiting red magnitude > 19).
The variable was designated PSN J09040080-7203248 when it was posted at the
Central Bureau's TOCP webpage and is here designated SN 2013B based on the
spectroscopic confirmation reported below.

     F. Taddia, J. Sollerman, G. Leloudas, and M. Ergon, Stockholm University;
M. T. Botticella, Istituto Nazionale di Astrofisica (INAF), Capodimonte
Astronomical Observatory; S. Benetti and A. Pastorello, INAF, Padova
Astronomical Observatory; S. Valenti, University of California at Santa
Barbara and Las Cumbres Observatory Global Telescope; S. Taubenberger,
Max-Planck-Institut fuer Astrophysik, Garching; S. J. Smartt, K. Smith, and
D. Young, Queen's University, Belfast; M. Sullivan, University of Southampton;
and A. De Cia, A. Gal-Yam, and O. Yaron, Weizmann Institute for Science,
on behalf of the PESSTO collaboration (see Valenti et al., as posted at
website URL http://www.astronomerstelegram.org/?read=4037), report that
optical spectroscopy (range 360-910 nm), obtained on Jan. 5.25 UT with the
New Technology Telescope (+ EFOSC2), show that PSN J09040080-7203248 = SN
2013B is a normal type-Ia supernova at redshift z = 0.038, close to maximum
light.  The expansion velocity, as deduced from the minimum of the Si II
635.5-nm absorption, is about 10700 km/s.  PESSTO classification spectra can
be obtained at website URL http://www.pessto.org/; classification is made via
SNID (Blondin and Tonry 2007, Ap.J. 666, 1024) and GELATO (Harutyunyan et al.
2008, A.Ap. 488, 383).

     N. Morrell, Las Campanas Observatory, Carnegie Supernova Project; and
Mansi Kasliwal, Observatories of the Carnegie Institution for Science, report
that an optical spectrum (range 375-930 nm) of PSN J09040080-7203248 = SN
2013B was obtained on Jan. 4.36 UT with the 6.5-m Magellan II (Clay)
telesscope (+ LDSS3), which reveals that this is a type-Ia supernova around
maximum brightness.  Cross-correlation with a library of supernova spectra
via the Supernova Identification code (SNID, Blondin and Tonry 2007, Ap.J.
1024, 666) gives excellent matches with a number of normal type-Ia supernovae
at ages between 6 days before and 1 day after maximum light, with a best
match to SN 2002aw at 1 day before maximum.  Adopting for the host galaxy the
NED recession velocity of 11381 km/s (Strauss et al. 1992, Ap.J. Suppl. 83,
29), the minimum of the Si II 635.5-nm absorption yields an expansion
velocity of 11000 km/s.


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

                         (C) Copyright 2013 CBAT
2013 January 7                   (CBET 3373)              Daniel W. E. Green