[IAUC] CBET 3044: 20120305 : SUPERNOVA 2012as IN UGC 9842 = PSN J15250852+3757494

Dom Mar 4 22:15:57 ART 2012

                                                  Electronic Telegram No. 3044
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 2012as IN UGC 9842 = PSN J15250852+3757494
     Zhangwei Jin (Ningbo, Zhejiang, China) and Xing Gao (Urumqi, Xinjiang,
China) report the discovery of a possible supernova (mag approximately 17.9)
on an unfiltered 40-s survey image (limiting mag about 19.5) taken by Xing Gao
in the course of the Xingming Sky Survey around Feb. 17.939 UT using a
Celestron C14 Schmidt-Cassegrain telescope at Mt. Nanshan.  The new object is
approximately located at R.A. = 15h25m08s.52, Decl. = +37d57'49".4 (equinox
2000.0), which is about 30".9 east and 12".9 north of the center of UGC 9842 =
PGC 55040.  The variable was designated PSN J15250852+3757494 when it was
posted at the Central Bureau's TOCP webpage and is here designated SN 2012as
based on the spectroscopic confirmation reported below.  Additional magnitudes
for 2012as:  1993 Apr. 17, [19.8 (Digitized Sky Survey, red plate; via Jin and
Gao); 2012 Feb. 11, [19.0 (Jin and Gao); 14.915, 18.7 (Jin and Gao; pre-
discovery; position end figures 08s.46, 49".4); 19.413, 17.6 (J. Brimacombe,
Cairns, Australia; remotely using a 51-cm RCOS telescope + STL11K camera +
luminance filter at the New Mexico Skies Observatory near Mayhill, NM, U.S.A.;
position end figures 08s.58, 50".2); 22.184, 17.6 (Federica Luppi and Luca
Buzzi, Varese, Italy; 0.38-m f/6.8 reflector; position end figures 08s.52,
49".7; reference stars from CMC-14 catalogue).  The Xingming images are posted
at website URL http://www.xjltp.com/XOSS/XM37ZJ/XM37ZJ.htm.  Brimacombe's
image is posted at URL http://www.flickr.com/photos/43846774@N02/6906737045/.
Luppi and Buzzi have posted their image at the following website URL:
http://www.astrogeo.va.it/pub/TOCP/PSN_P55040.jpg.

     M. Fraser, T.-W. Chen, S. J. Smartt, and R. Kotak, Queen's University,
Belfast, report that they obtained a spectrum (range 530-975 nm; resolution
about 1.3 nm) of PSN J15250852+3757494 = SN 2012as on Mar. 4.28 UT with the
4.2-m William Herschel Telescope (+ ISIS).  The spectrum appears similar to
that of a type-IIn supernova, with a blue continuum and a narrow emission
feature from H_alpha.  Note that, at the distance of the host galaxy, the
supernova has an absolute magnitude of -18, which strongly disfavors this
being a supernova impostor.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
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                         (C) Copyright 2012 CBAT
2012 March 5                     (CBET 3044)              Daniel W. E. Green