Electronic Telegram No. 4126
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@eps.harvard.edu (alternate cbat@iau.org)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network


SUPERNOVA 2015P IN MCG -02-33-20 = PSN J12503072-1052405
     Stuart Parker, Canterbury, New Zealand, reports the discovery of an
apparent supernova (red mag 18.2) on a 30-s unfiltered CCD image (limiting
mag 19) taken on June 7.385 UT with a 35-cm Celestron C14 reflector (+ ST10
camera) at his Parkdale Observatory in the course of the Backyard Observatory
Supernova Search.  The new object is located at R.A. = 12h50m30s.72, Decl. =
-10d52'40".5 (equinox 2000.0; reference stars from USNO-B and UCAC4
catalogues), which is 19" east and 84" south of the nucleus of the galaxy
MCG -02-33-20.  Nothing is visible at this position on Digitized Sky Survey
red and infrared images (limiting red magnitude > 19).  An image of the
variable can be viewed via website URL http://tinyurl.com/o7fsfv6.  The
variable was designated PSN J12503072-1052405 when it was posted at the
Central Bureau's TOCP webpage and is here designated SN 2015P based on the
spectroscopic confirmation reported below.  SN 2008aq also appeared in MCG
-02-33-20 (cf. CBET 1271).  G. Masi and P. Catalano write that unfiltered
CCD exposures taken on June 9.86 with a 43-cm telescope at Ceccano, Italy,
show 2015P at mag 17.8 with position end figures 30s.74, 40".4.

     N. Morrell and B. Shappee, Carnegie Observatories, report that optical
spectroscopy (range 370-910 nm) of PSN J12503072-1052405 = SN 2015P, obtained
on June 21 UT with the du Pont 2.5-m telescope (+ WFCCD) at Las Campanas
Observatory, reveal that it is a type-II supernova.  SN 2015P is rather
evolved, displaying well-developed P-Cyg profiles of Balmer, He I, and Ca II
infrared lines.  Assuming for MCG -02-33-20 a recession velocity of 7427 km/s
(Koribalski et al. 2004, A.J. 128, 16; via NED), they derive for the minimum
of the H-beta absorption an expansion velocity of about 7300 km/s.  Comparison
with a library of supernova spectra using the Supernova Identification Tool
(SNID; Blondin and Tonry 2007, Ap.J. 666, 1024) yields many good matches with
type II-P supernovae at 4-6 weeks past maximum, with a best match to SN 2004et
at +47 days.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2015 CBAT
2015 July 29                     (CBET 4126)              Daniel W. E. Green