[IAUC] CBET 3873: 20140517 : SUPERNOVA 2014ba IN NGC 7410 = PSN J22550197-3939345

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                                                  Electronic Telegram No. 3873
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 2014ba IN NGC 7410 = PSN J22550197-3939345
     Stuart Parker, Canterbury, New Zealand, reports the discovery of an
apparent supernova (red mag 14.7) on a 30-s unfiltered CCD image (limiting mag
18) taken by himself on May 7.758 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.  The new object is located at
R.A. = 22h55m01s.97, Decl. = -39d39'34".5 (equinox 2000.0; reference stars
from USNO-B and UCAC4 catalogues), which is 12" east and 6" north of the
nucleus of the galaxy NGC 7410.  Nothing is visible at this position on
Digitized Sky Survey red and infrared images (limiting red magnitude > 19).
An image of the variable was posted at website URL http://tinyurl.com/k3tabj6.
The variable was designated PSN J22550197-3939345 when it was posted at the
Central Bureau's TOCP webpage and is here designated SN 2014ba based on the
spectroscopic confirmation reported below.

     D. Milisavljevic, J. Parrent, R. Margutti, and A. Soderberg, Harvard-
Smithsonian Center for Astrophysics; R. Fesen, Dartmouth College; and P.
Vaisanen, South African Astronomical Observatory and Southern African Large
Telescope, report that low-dispersion spectra (range 330-900 nm), obtained on
May 12.1 UT with the 10-m SALT telescope (+ RSS), show PSN J22550197-3939345
= SN 2014ba to be a peculiar type-Ia supernova.  Cross-correlation with a
library of supernova spectra using the "Supernova Identification" code (SNID;
Blondin and Tonry 2007, Ap.J. 666, 1024) shows similarity to a variety of
sub-luminous 1991bg-like events including 2005bl and 2007al at approximately
1-3 weeks after maximum light.  After removal of the host-galaxy (NGC 7410)
redshift of z = 0.0058 (via NED; Lauberts and Valentijn 1989, Surface
Photometry Catalogue of the ESO-Uppsala Galaxies), fitting with the SYN++
software (Thomas et al. 2011, PASP 123, 237) suggests that the broadest P-Cyg
absorption minima associated with the Ca II and O I ions are blueshifted by
approximately 10000 km/s.


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                         (C) Copyright 2014 CBAT
2014 May 17                      (CBET 3873)              Daniel W. E. Green