Electronic Telegram No. 3569
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@eps.harvard.edu (alternate cbat@iau.org)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network


SUPERNOVA 2013dm IN ESO 445-G56 = PSN J13505285-3017097
     E. Conseil reports the discovery of an apparent supernova (R-band mag
about 18.4) on public images taken with the TAROT 0.25-m robotic telescope at
La Silla, Chile, on May 2.22 UT.  The new object is located at approximately
R.A. = 13h50m52s.85, Decl. = -30o17'09".7 (equinox 2000.0), which is 12" west
and 12" north of the nucleus of ESO 445-G56.  Nothing is visible at this
position on an image (presumably from the TAROT telescope but with no limiting
magnitude provided) taken on 2012 May 17.  A TAROT image is posted at website
URL http://cador.obs-hp.fr/sn_tarot/PSN_J13505285-3017097/.  The variable was
designated PSN J13505285-3017097 when it was posted at the Central Bureau's
TOCP webpage and is here designated SN 2013dm based on the spectroscopic
confirmation reported below.  Additional CCD magnitudes for 2013dm:  May 5.26,
R = 17.2 (TAROT); 8.27, R = 16.5 (TAROT); 14.25, R = 15.7 (TAROT); 17.00, R =
16.1 (TAROT); 20.23, R = 16.2 (TAROT); 26.22, R = 16.3 (TAROT); 29.411, 16.2
(Joseph Brimacombe, Cairns, Australia; 41-cm telescope + infrared filter;
bandpass > 700 nm; position end figures 52s.89, 09".5; image posted at URL
http://www.flickr.com/photos/43846774@N02/8885079486/); June 2.603, 16.1
(Brimacombe; position end figures 52s.90, 09".4; image posted at website URL
http://www.flickr.com/photos/43846774@N02/8956624307/).

     M. Childress, R. Scalzo, B. Tucker, F. Yuan, and B. Schmidt, Australian
National University (ANU), report on spectroscopy of PSN J13505285-3017097 =
SN 2013dm obtained with the Wide Field Spectrograph (WiFeS; Dopita et al.
2007, Ap. Space Sci. 310, 255) on the ANU 2.3-m telescope at Siding Spring
Observatory using the B3000/R3000 gratings (range 350-980 nm; 0.1-nm
resolution).  A 40-min spectrogram taken on June 22.38 UT shows clear
signatures of an old type-Ia supernova, including strong Fe absorption
features around 500.0 nm, absence of the Si II 635.5-nm feature due to nearby
Fe features, and absorption in the Ca II infrared triplet.  Classification
with SNID (Blondin and Tonry 2007, Ap.J. 666, 1024) shows a good match to SN
2008bf at +39 days; the mean redshift from SNID is about 0.022 +/- 0.006,
consistent with the redshift of the apparent host galaxy, ESO 445-G56 (z =
0.018953 from Kuntschner et al. 2002, MNRAS 337, 172; via NED).


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

                         (C) Copyright 2013 CBAT
2013 July 1                      (CBET 3569)              Daniel W. E. Green