[IAUC] CBET 2902: 20111116 : SUPERNOVA 2011hs IN IC 5267 = PSN J22571177-4323048

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                                                  Electronic Telegram No. 2902
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 2011hs IN IC 5267 = PSN J22571177-4323048
     Colin Drescher, Calamvale, Queensland, Australia, reports the discovery
by Stuart Parker (Oxford, Canterbury, New Zealand) of an apparent supernova
(red mag 15.5, measured by Drescher) on a 30-s unfiltered CCD image taken on
Nov. 12.476 UT using a 35-cm Celestron C14 reflector (+ ST10 CCD camera).  The
new object is located at R.A. = 22h57m11s.77, Decl. = -43d23'04".8 (equinox
2000.0), which is 20" west and 41" north of the nucleus of the galaxy IC 5267.
The variable was designated PSN J22571177-4323048 when it was posted on the
Central Bureau's TOCP webpage and is here designated SN 2011hs based on the
spectroscopic confirmation reported below.  Additional CCD magnitudes for
2011hs:  Oct. 9.574, [18.7 (Parker; unfiltered red CCD); Nov. 13.439, 15.4
(Joseph Brimacombe, Cairns, Australia; infrared filter; optical wavelength >
700 nm; position end figures 11s.75, 04".6; image posted at the following
website URL:  http://www.flickr.com/photos/43846774@N02/6339635453/).

     D. Milisavljevic, Harvard-Smithsonian Center for Astrophysics (CfA); R.
Fesen, Dartmouth College; A. Soderberg, CfA; and T. Pickering and P. Kotze,
South African Astronomical Observatory, report that low-dispersion spectra
(range 320-900 nm), obtained on Nov. 14.9 UT with the 10-m SALT telescope (+
RSS), show PSN J22571177-4323048 = SN 2011hs to be a type-IIb supernova.
Comparison with spectra retrieved from the Supernova Spectrum Archive
(SUSPECT; cf. website URL http://bruford.nhn.ou.edu/~suspect/index.html) shows
a good match to the type-IIb supernova 2003bg at 15 days before maximum light
(Hamuy et al. 2009, Ap.J. 703, 1612).  Assuming a redshift of z = 0.00571 for
the host galaxy, IC 5267 (Koribalski et al. 2004, A.J. 128, 16), the velocity
at the minimum of the H-alpha absorption is measured to be approximately
-18300 km/s.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2011 CBAT
2011 November 16                 (CBET 2902)              Daniel W. E. Green