[IAUC] CBET 3224: 20120914 : SUPERNOVA 2012er IN PGC 60437 = PSN J17315266+7150120

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                                                  Electronic Telegram No. 3224
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 2012er IN PGC 60437 = PSN J17315266+7150120
     D. Denisenko, Sternberg Astronomical Institute, Moscow State University,
reports the discovery by S. Shurpakov of an apparent supernova (mag 16.0) on
two unfiltered 60-s images obtained with the 0.40-m f/2.5 MASTER-Amur robotic
telescope (+ 16-megapixel CCD camera) on Aug. 21.564 and 21.595 UT.  The new
object is located at R.A. = 17h31m52s.66, Decl. = +71d50'12".0 (equinox
2000.0), which is 14".7 west and 13".8 south of the nucleus of PGC 60437.
Nothing was visible at this position on a MASTER-Amur unfiltered image taken
on July 23.56 (limiting magnitude 19.0).  The discovery image is posted at
URL http://master.sai.msu.ru/static/OT/PSNJ17315266+7150120-MASTER.jpg.  The
variable was designated PSN J17315266+7150120 when it was posted at the
Central Bureau's TOCP webpage and is here designated SN 2012er based on the
spectroscopic confirmation reported below.  Additional unfiltered CCD
magnitudes for 2012er:  Aug. 22.154, 17.2 (R. A. Koff, Bennett, CO, USA;
Meade 0.25-m f/10 reflector + SBIG ST-9E camera; limiting magnitude 18.0;
position end figures 52s.52, 08".9; UCAC3 reference stars); Aug. 28.007,
17.5 (David Grennan, Dublin, Ireland; 35-cm Schmidt-Cassegrain telescope;
position end figures 52s.67, 10".3); Sept. 13.840, R_c = 17.6 (Massimiliano
Martignoni, Magnago, Italy; 0.25-m f/10 Schmidt-Cassegrain reflector;
position end figures 52s.64, 09".5).

     M. Turatto, S. Benetti, A. Pastorello, L. Tomasella, M. Fiaschi, P.
Ochner, E. Cappellaro, and S. Valenti, Osservatorio Astronomico di Padova,
Istituto Nazionale di Astrofisica, report that a spectrogram of PSN
J17315266+7150120 = SN 2012er, obtained on Aug 21.86 UT with the Asiago 1.82-m
Copernico Telescope (+ AFOSC; range 340-820 nm; resolution 1.4nm), shows the
typical features of a normal type-Ia supernova.  Adopting for the host galaxy
(PGC 60437) the redshift z = 0.039694 (Falco et al. 1999, PASP 111, 438; via
NED), the best fit with the GELATO (Harutyuyan et al. 2008, A.Ap. 488, 383)
library of supernovae spectra is with that of SN 1989B obtained at six days
after B-band maximum.  The photospheric velocity derived from the Si II
doublet is 11000 km/s.


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                         (C) Copyright 2012 CBAT
2012 September 14                (CBET 3224)              Daniel W. E. Green