[IAUC] CBET 3101: 20120506 : SUPERNOVA 2012ca = PSN J18410706-4147374

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                                                  Electronic Telegram No. 3101
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)
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Prepared using the Tamkin Foundation Computer Network


SUPERNOVA 2012ca = PSN J18410706-4147374
     Colin Drescher, Calamvale, Queensland, Australia, reports the discovery
of an apparent supernova (red mag 14.8) by Stuart Parker (Oxford, Canterbury,
New Zealand) in the course of the Backyard Observatory Supernova Search on a
30-s unfiltered CCD image taken on Apr. 25.587 UT using a 35-cm Celestron C14
f/6.3 reflector (+ ST10 camera).  The new object is located at R.A. =
18 41 07.25 Dec -41 47 38.4 (equinox 2000.0), which is 8" west and 4" north of
the nucleus of the galaxy ESO 336-9.  The variable was designated PSN
J18410706-4147374 (based on a more poorly measured position) when it was
posted at the Central Bureau's TOCP webpage and is here designated SN 2012ca
based on the spectroscopic confirmation reported below.  Additional magnitudes
for 2012ca:  1990 July 21, [19.6 (Digitized Sky Survey red image; via
Drescher); 2012 Apr. 27.421, 14.5 (Parker; position end figures 07s.25, 38".7;
very low altitude; measured by Drescher); 28.467, 15.0 (Joseph Brimacombe,
Cairns, Australia; infrared filter; position end figures 07s.22, 39".2; image
posted at website URL http://www.flickr.com/photos/43846774@N02/7122296129/).

     C. Inserra and S. J. Smartt, Queen's University of Belfast; S. Valenti,
A. Pastorello, E. Cappellaro, and S. Benetti, Istituto Nazionale di
Astrofisica, Padova Astronomical Observatory; S. Benitez-Herrera and S.
Taubenberger, Max-Planck-Institut fuer Astrophysik, Garching; M. Sullivan,
University of Oxford; and R. Scalzo, Australian National University, on behalf
of the PEESTO collaboration (see Valenti et al., as posted at website URL
http://www.astronomerstelegram.org/?read=4037), report that an optical
spectrum (range 360-910 nm) of PSN J18410706-4147374 = SN 2012ca, obtained on
Apr. 29.40 UT (see http://www.astronomerstelegram.org/?read=4076) at the 3.6-m
New Technolog Telescope (+ EFOSC2) at La Silla, shows it to be a type-IIn
supernova.  Adopting a recession velocity of 5834 km/s for ESO 366-G9
(Strauss et al. 1992, Ap.J. Suppl. 83, 29; via NED), the best fit to this
spectrum found by GELATO (Harutyunyan et al. 2008, A.Ap. 488, 383; publicly
available at https://gelato.tng.iac.es) is with the spectrum of the type-IIn
supernova 1997cy at about 20 days from the presumed explosion epoch.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
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                         (C) Copyright 2012 CBAT
2012 May 6                       (CBET 3101)              Daniel W. E. Green