Electronic Telegram No. 3459
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 2012il
     A. J. Drake, S. G. Djorgovski, M. J. Graham, A. Mahabal, and R. Williams,
California Institute of Technology; J. L. Prieto, Princeton University; M.
Catelan, Pontificia Universidad Catolica de Chile; and S. M. Larson and E.
Christensen, Lunar and Planetary Laboratory, University of Arizona, report the
Catalina Real-time Transient Survey discovery of an apparent supernova in
unfiltered Catalina Sky Survey (CSS) images:

   SN       2012 UT       R.A. (2000.0) Decl.      Mag.
   2012il   Jan. 21.33   9 46 12.85  +19 50 28.2   18.1

Further magnitudes for 2012il from Drake:  2011 Dec. 25.40 UT, [20.4 (CSS);
Dec. 31.49, 18.8 (CSS); 2012 Jan. 14.53, 18.1 (CSS); 25.31, g = 18.3, r =
18.4 (Palomar 1.5-m reflector); Feb. 11.42, 18.8 (CSS); 22.28, 19.1 (CSS).

     C. Inserra, S. J. Smartt, M. Fraser, D. Young, K. Smith, D. Wright, R.
Kotak, M. McCrum, L. Magill, and T.-W. Chen, Queen's University, Belfast; A.
Pastorello and S. Benetti, Osservatorio Astronomico di Padova, Istituto
Nazionale di Astrofisica; S. Valenti,  Las Cumbres Observatory Global
Telescope and University of California at Santa Barbara; F. Bresolin, R.
Kudritzki, J. Tonry, E. Magnier, M. Huber, K. Chambers, N. Kaiser, J. Morgan,
W. Burgett, J. Heasley, W. Sweeney, C. Waters, and H. Flewelling, University
of Hawaii; C. Stubbs, Harvard University; P. A. Price, Princeton University;
J. Sollerman, F. Taddia, and M. Ergon, Oscar Klein Centre, Stockholm; G.
Leloudas, Dark Cosmology Centre, Copenhagen; and S. Taubenberger,
Max-Planck-Institut fuer Astrophysik, Garching, report the independent
discovery of 2012il at magnitude g = 18.33 +/- 0.01 (in the PS1 system; cf.
Tonry et al. 2012, Ap.J. 745, 42) on 2012 Jan. 19.9 UT in the course of the
Pan-STARRS1 3Pi Faint Galaxy Supernova Survey, reporting the position as R.A.
= 9h46m12s.91, Decl. = +19d50'28".7 (equinox 2000.0), which is within 0".12
of the position of the faint galaxy SDSS J094612.91+195028.6 (which has
listed a g magnitude of about 22.1).  A low-resolution spectrogram of 2012il
was obtained on 2012 Jan. 29.0 with the Nordic Optical Telescope (+ ALFOSC;
range 320-910 nm).  Host-galaxy nebular emission lines of H-alpha, H-beta,
and [O III] give an unambiguous redshift of z = 0.175, suggesting that the
transient is very luminous, with absolute g magnitude -21.1.  The spectrum
shows a blue continuum with broad and shallow absorption features, similar
to that of SN 2010gx (cf. CBET 2413) at 1-2 weeks after maximum light
(Pastorello et al. 2010, Ap.J. 724, L16).


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

                         (C) Copyright 2013 CBAT
2013 April 10                    (CBET 3459)              Daniel W. E. Green