Electronic Telegram No. 1722
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
CBAT@CFA.HARVARD.EDU (science)
URL http://www.cfa.harvard.edu/iau/cbat.html


SUPERNOVA 2009at IN NGC 5301
     A. Harutyunyan, Telescopio Nazionale Galileo (TNG); and F. Bufano and S.
Benetti, Istituto Nazionale di Astrofisica, Osservatorio Astronomico di
Padova, report that a spectrogram (range 350-780 nm, resolution 1.4 nm) of
2009at (cf. CBET 1718), obtained on Mar. 14.00 UT with the TNG (+ DOLORES),
shows it to be a young type-II supernova.  Assuming a recession velocity of
1503 km/s (Sloan Digital Sky Survey data release 4, 2005; via NED) for the
host galaxy, the "GELATO" spectrum-comparison code (Harutyunyan et al. 2008,
A.Ap. 488, 383; available at https://gelato.tng.iac.es) provides good fits
to spectra of type-II supernovae near explosion.  One of the fits, with SN
2008aw at ten days after discovery, can be seen at the following website URL:
https://gelato.tng.iac.es/plots/plot_TiEepj0QK72n.png.  The expansion
velocity deduced from the H-alpha absorption is about 11700 km/s.
     Further to CBET 1718, S. Nakano clarifies that he simply averaged ten
measurements that were made by Ikari.  Corrigendum:  on line 10, FOR  Nov.
11.760, READ  Mar. 11.760,
     E. Prosperi, Larciano, Italy, reports that 2009at was at unfiltered CCD
mag 15.5 on Mar. 12.919 UT (0.35-m f/10 Schmidt-Cassegrain reflector).


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2009 CBAT
2009 March 15                    (CBET 1722)              Daniel W. E. Green