[IAUC] CBET 2737: 20110605 : SUPERNOVA 2011di IN IC 4754 = PSN J18435900-6159460

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                                                  Electronic Telegram No. 2737
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 2011di IN IC 4754 = PSN J18435900-6159460
     L. A. G. Monard, Pretoria, South Africa, reports his discovery of an
apparent supernova (mag 17.5) on several unfiltered CCD images obtained on
May 13.005 UT at the Klein Karoo Observatory.  The new object, which was
designated PSN J18435900-6159460 when posted on the Central Bureau's TOCP
webpage and is here designated SN 2011di based on the spectroscopic report
below, is located at R.A. = 18h43m59s.06, Decl. = -61d59'46".3, which is 9"
west and 21" south of the core of the SBb-type galaxy IC 4754; Monard notes
that a faint star just south of the galaxy's core must somewhat affect the
accuracy of the derived position.  Nothing is visible at this position on
Digitized Sky Survey images (limiting red mag 20.5) or on 2010 images taken
at Monard's Bronberg Observatory (limiting mag 18.5 and fainter).  Additional
magnitudes for 2011di:  2011 Apr. 30.102, [18.8 (Monard); May 14.894, 16.5
(Monard); 15.134, 16.5 (Monard); 15.875, 16.2 (Monard); 17.880, 15.7
(Monard); 22.740, 14.8 (Joseph Brimacombe, Coral Towers Observatory, Cairns,
Australia, 30-cm telescope + STL6K camera + red filter; position end figures
59s.12, 45".7); 23.725, 14.7 (Brimacombe); 24.658, 14.7 (Brimacombe); 25.756,
14.7 (Brimacombe).  Brimacombe's May 22 image is posted at the following
website URL:  http://www.flickr.com/photos/43846774@N02/5748796850/.

     D. Milisavljevic and R. Fesen, Dartmouth College; K. Nordsieck, University
of Wisconsin; and T. Pickering and D. O'Donoghue, South African Astronomical
Observatory, on behalf of a larger SALT Commissioning Team, report that low-
dispersion spectra (range 350-750 nm), obtained May 28 UT with the 10-m SALT
telescope (+ RSS), show PSN J18435900-6159460 = SN 2011di to be a type-Ia
supernova.  Cross-correlation with a library of supernova spectra using the
"Supernova Identification" code (SNID; Blondin and Tonry 2007, Ap.J. 666,
1024) shows matches with normal type-Ia events at less than one week after
maximum light.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
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                         (C) Copyright 2011 CBAT
2011 June 5                      (CBET 2737)              Daniel W. E. Green