Electronic Telegram No. 3904
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 2014bs IN NGC 5270 = PSN J13420922+0415447
     S. Howerton, Arkansas City, KS, U.S.A.; A. J. Drake, S. G. Djorgovski, A.
Mahabal, M. J. Graham, and R. Williams, California Institute of Technology;
J. L. Prieto, Princeton University; M. Catelan, Pontificia Universidad
Catolica de Chile; and E. Christensen and S. M. Larson, Lunar and Planetary
Laboratory, University of Arizona, report the Catalina Real-time Transient
Survey discovery of an apparent supernova in public images from the Catalina
Sky Survey (CSS):

 SN       2014 UT       R.A. (2000.0) Decl.      Mag.      Offset
 2014bs   May 30.25   13 42 09.72  + 4 15 44.7   18.9    17".4 E, 0".6 N

The variable was designated PSN J13420922+0415447 when it was posted at the
Central Bureau's TOCP webpage and is here designated SN 2014bs based on the
spectroscopic confirmation reported below.  Additional CCD magnitudes for
2014bs:  May 18.22 UT, [19.7 (CSS); 30.933, 17.7 (Howerton; iTelescope 0.43-m
telescope + luminance filter at the AstroCamp Observatory, Nerpio, Spain;
image posted at URL https://www.flickr.com/photos/watchingthesky/14306766142);
31.957, 17.3 (X. Bros, Catalonia, Spain; 35-cm telescope; position end figures
09s.72, 44".8; image posted at URL http://www.anysllum.com/PSN_NGC5270.jpg);
31.985, 17.4 (G. Masi; remotely using a 43-cm telescope at Ceccano, Italy;
position end figures 09s.74, 44".9); June 2.487, V = 17.1 (Howerton; image
posted at URL https://www.flickr.com/photos/watchingthesky/14146704597).

     D. D. Balam, Dominion Astrophysical Observatory, National Research
Council of Canada; M. L. Graham, Las Cumbres Observatory Global Telescope,
University of California at Santa Barbara; and E. Y. Hsiao, Las Campanas
Observatory, report that a spectrogram (range 369-700 nm, resolution 0.3 nm)
of PSN J13420922+0415447 = SN 2014bs, obtained on June 5.29 UT with the 1.82-m
Plaskett Telescope of the National Research Council of Canada, shows it to be
a type-Ia supernova about one week after maximum light.  Cross-correlation
with a library of supernova spectra using the "Supernova Identification" code
(Blondin and Tonry 2007, Ap.J. 666, 1024) indicates that 2014bs is most
similar to the type-Ia supernova 2000cx at eight days post-maximum light.  The
photospheric velocity estimated from the Si II 635.5-nm feature is about
11800 km/s.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2014 CBAT
2014 June 17                     (CBET 3904)              Daniel W. E. Green