[IAUC] CBET 2820: 20110920 : SUPERNOVA 2011fp IN NGC 57 = PSN J00152561+1719119

Lun Sep 19 22:58:35 ART 2011

                                                  Electronic Telegram No. 2820
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 2011fp IN NGC 57 = PSN J00152561+1719119
     S. Nakano, Sumoto, Japan, reports the discovery by Koichi Itagaki
(Teppo-cho, Yamagata) of an apparent supernova (mag 17.9) on a 15-s unfiltered
CCD frame (limiting magnitude 19.0) taken on Aug. 29.71 UT using a 0.60-m
f/5.7 reflector (+ BITRAN BT-21 camera).  The new object is located at R.A. =
0h15m25s.61, Decl. = +17d19'11".9 (equinox 2000.0), which is 76" west and 31"
south of the center of NGC 57.  Nothing is visible at this position on the
Digitized Sky Survey (limiting mag about 21; no bandpass or date provided).
When it was posted on the Central Bureau's TOCP webpage, the variable was
assigned the preliminary designation PSN J00152561+1719119, while it is here
assigned the permanent designation SN 2011fp based on the spectroscopic
report below.  Additional unfiltered CCD magnitudes reported for 2011fp:
2007 Aug. 20.66, [19.5 (Itagaki); 2011 Aug. 2.60, [18.5 (Itagaki); 21.676,
17.5 (K. Nishimura, Ebetsu, Hokkaido, Japan, 0.35-m reflector; pre-discovery;
communicated by H. Yamaoka, Kyushu University); 26.659, 17.6 (Itagaki;
pre-discovery; position end figures 25s.62, 12".0); 28.558, 17.7 (Itagaki;
pre-discovery; position end figures 25s.59, 12".0); 30.697, 18.1 (Joseph
Brimacombe, Cairns, Australia; infrared filter, no specific bandpass or type
of filter given; position end figures 25s.63, 12".2; image posted at URL
http://www.flickr.com/photos/43846774@N02/6098209135/); Sept. 7.485, 17.9 (T.
Noguchi, Katori, Chiba-ken, Japan; 0.23-m Schmidt-Cassegrain reflector +
BITRAN BT-11E CCD; position end figures 25s.50, 11".5 via UCAC3 reference
stars; from eight co-added 50-s exposures; limiting mag 18.5; communicated
by Nakano).  Itagaki has posted his discovery image at the following website
URL:  http://www.k-itagaki.jp/images/psn-0057.jpg.

     L. Magill, Queen's University, Belfast, and Isaac Newton Group; R. Kotak
and S. Smartt, Queen's University, Belfast; and A. Pastorello, Osservatorio
Astronomico di Padova, Istituto Nazionale di Astrofisica, report that an
optical spectrogram (range 330-900 nm) of PSN J00152561+1719119 = SN 2011fp
was obtained at the William Herschel Telescope (+ ISIS spectrograph) by K.
Maguire on Sept. 2.99 UT.  The spectrum shows broad spectral features.
Cross-correlation with a library of supernova spectra using the "Supernova
Identification" code (SNID; Blondin and Tonry 2007, Ap.J. 666, 1024) suggests
a normal type-Ia supernova, similar to SN 1991bg at 19 days post-peak
(Filippenko et al. 1992, Ap.J. 104, 6224) or SN 2004S (Krisciunas et al.
2007, Ap.J. 133, 58) at 36 days post-peak.


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

                         (C) Copyright 2011 CBAT
2011 September 20                (CBET 2820)              Daniel W. E. Green