[IAUC] CBET 3431: 20130305 : SUPERNOVA 2013ai IN NGC 2207 = PSN J06161835-2122329

[quai en eps.harvard.edu]

                                                  Electronic Telegram No. 3431
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 2013ai IN NGC 2207 = PSN J06161835-2122329
     Alain Klotz, Institut de Recherche en Astrophysique et Planetologie
(IRAP), Toulouse, reports the discovery by E. Conseil (IRAP) of an apparent
supernova (R-band magnitude about 17.4) on images taken on Mar. 1.66 UT with
the Zadko 1-m telescope at the Gingin observatory in Australia.  The new
object is located at R.A. = 6h16m18s.35, Decl. = -21o22'32".9 (equinox 2000.0),
which is 51" west and 11" south of the nucleus of NGC 2207; nothing was
visible at this position on an image taken on Feb. 6.72.  Images have been
posted at website URL http://cador.obs-hp.fr/sn_tarot/PSN_J06161835-2122329/.
The variable was designated PSN J06161835-2122329 when it was posted at the
Central Bureau's TOCP webpage (with the offset in declination given there by
mistake as 11" north) and is here designated SN 2013ai based on the
spectroscopic confirmation reported below.  Additional CCD magnitudes for
2013ai:  Feb. 26.66, R = 19.3 (Conseil and Klotz; prediscovery); 28.66, R =
18.6 (Conseil and Klotz; prediscovery); Mar. 3.185, 17.0 (Joseph Brimacombe,
Cairns, Australia; stacked images obtained remotely with a 51-cm RCOS
telescope + luminance filter at the New Mexico Skies observatory near Mayhill,
NM, U.S.A.; position end figures 18s.42, 31".0; image posted at website URL
http://www.flickr.com/photos/43846774@N02/8526368927/); 3.890, 16.8 (Federica
Luppi and Luca Buzzi, Varese, Italy; 0.38-m f/6.8 reflector; unfiltered;
position end figures 18s.38, 32".9; reference stars from the NOMAD catalogue;
image posted at URL http://www.astrogeo.va.it/pub/TOCP/PSN_N2207.jpg).

     M. Fraser and C. Inserra, Queen's University, Belfast; N. Walton and N.
Blagorodnova, Institute of Astronomy, Cambridge; M. Nicholl, Queen's
University, Belfast; S. Benetti and A. Pastorello, Istituto Nazionale di
Astrofisica, Padova Astronomical Observatory; S. Valenti, Las Cumbres
Observatory Global Telescope and University of California at Santa Barbara;
S. Taubenberger, Max-Planck-Institut fuer Astrophysik, Garching; S. J. Smartt,
K. Smith, and D. Young, Queen's University, Belfast; M. Sullivan, University
of Southampton; and A. Gal-Yam and O. Yaron, Weizmann Institute for Science,
on behalf of the PESSTO collaboration (www.pessto.org), report that they
obtained a spectrogram of PSN J06161835-2122329 = SN 2013ai on Mar. 3, using
the European Southern Observatory's New Technology Telescope (+ EFOSC2 with
Grism#13) at La Silla.  The spectrum consists of a blue continuum, with a
broad absorption from H_alpha, and is consistent with a young type-II
supernova in NGC 2207.  Narrow H_alpha emission is also seen in the
spectrum, likely arising from the host galaxy.


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

                         (C) Copyright 2013 CBAT
2013 March 5                     (CBET 3431)              Daniel W. E. Green