[IAUC] CBET 2807: 20110903 : SUPERNOVA 2011fm IN IC 4815 = PSN J19065017-6141577

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                                                  Electronic Telegram No. 2807
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 2011fm IN IC 4815 = PSN J19065017-6141577
     Colin Drescher, Calamvale, Queensland, Australia, reports the discovery
of an apparent supernova by Stuart Parker (Oxford, Canterbury, New Zealand)
on a 30-s unfiltered CCD image taken on Aug. 22.359 UT using a 35-cm Celestron
C14 f/6.3 reflector (+ ST10 camera).  Drescher measured the new object's (red)
magnitude to be 16.4 and its position to be R.A. = 19h06m50s.17, Decl. =
-61d41'57".7 (equinox 2000.0), which is 3" west and 7" north of the nucleus
of the galaxy IC 4815.  The variable was designated PSN J19065017-6141577
when it was posted on the Central Bureau's TOCP webpage and is here designated
SN 2011fm based on the spectroscopic report below.  Additional unfiltered CCD
magnitudes reported for 2011fm:  1989 Aug. 29, [20.7 (Digitized Sky Survey
red plate; via Drescher); 2011 July 16.608, [18.9 (Parker; red); Aug. 23.318,
16.5 (Parker, via Drescher); 23.567, 17.9 (Joseph Brimacombe, Cairns,
Australia; position end figures 50s.10, 57".6; image posted at website URL
http://www.flickr.com/photos/43846774@N02/6075195108/).

     N. Morrell, Las Campanas Observatory, Carnegie Supernova Project,
reports on a spectrum (range 360-920 nm) of PSN J19065017-6141577 = SN 2011fm
obtained on Sept. 1.20 UT with the Las Campanas du Pont 2.5-m telescope (+
WFCCD).  Inspection of the data shows that 2011fm is a type-Ia supernova at
2 or 3 weeks past maximum light.  Cross-correlation with a library of
supernova spectra using the Supernova Identification tool (SNID; Blondin and
Tonry 2007, Ap.J. 666, 1024) produces a number of good matches with normal
type-Ia supernovae between 12 and 20 days after maximum brightness.  The
minimum of the Si II 635.5-nm absorption is blueshifted by approximately 9800
km/s if the NED recession velocity of 8313 km/s (Kowalski et al. 1987, A.J.
93, 1350) is assumed for IC 4815.  Significant Na I absorption (equivalent
width 0.22 nm) at the redshift of the host galaxy is observed in the
supernova spectrum.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2011 CBAT
2011 September 3                 (CBET 2807)              Daniel W. E. Green