[IAUC] CBET 4132: 20150805 : SUPERNOVA 2015T IN ESO 147-G20 = PSN J23072407-6129212

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                                                  Electronic Telegram No. 4132
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 2015T IN ESO 147-G20 = PSN J23072407-6129212
     Stuart Parker, Canterbury, New Zealand, reports the discovery of an
apparent supernova (red mag 17.3) on a 30-s unfiltered CCD image (limiting
mag 18.5) taken by himself on June 16.681 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. = 23h07m24s.07, Decl. = -61d29'21".2 (equinox 2000.0;
reference stars from USNO-B and UCAC4 catalogues), which is 6" east and 5"
south of the nucleus of the galaxy ESO 147-G20.  Nothing is visible at this
position on Digitized Sky Survey red and infrared images (limiting red mag >
19).  An image of the variable is viewable at URL http://tinyurl.com/q6dt5hu.
The variable was designated PSN J23072407-6129212 when it was posted at the
Central Bureau's TOCP webpage and is here designated SN 2015T based on the
spectroscopic confirmation reported below.

     N. Morrell and B. Shappee, Carnegie Observatories, report on optical
spectroscopy (range 370-910 nm) of PSN J23072407-6129212 = SN 2015T obtained
on June 21 UT with the du Pont 2.5-m telescope (+ WFCCD) at Las Campanas
Observatory, revealing that it is a type-II supernova.  The spectrum of
2015T consists of a blue continuum with superimposed incipient P-Cyg
profiles of Balmer and He I 587.6-nm lines, consistent with a type-II
supernova shortly after explosion.  Using for the host galaxy (ESO 147-G20)
the NED recession velocity of 8122 km/s (Jones et al. 2009, The 6dF Galaxy
Survey Data Release 3), Morrell and Shappee find that the minimum of the
H-beta absorption is blueshifted by approximately 12000 km/s.  The best match
found using the SNID software is SN 2006bp at 3 days after maximum light.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2015 CBAT
2015 August 5                    (CBET 4132)              Daniel W. E. Green



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