Electronic Telegram No. 647
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://cfa-www.harvard.edu/iau/cbat.html


SUPERNOVA 2006gy IN NGC 1260
     A. Harutyunyan, S. Benetti, M. Turatto, E. Cappellaro, and N.
Elias-Rosa, Istituto Nazionale di Astrofisica, Osservatorio Astronomico di
Padova; and G. Andreuzzi, Telescopio Nazionale Galileo (TNG), report that
a spectrum of 2006gy (cf. CBET 644), obtained on Sept. 26.07 UT with the
3.5-m TNG (+ DOLORES; range 340-920 nm, resolution 1.2 nm), shows it to be
a type-II supernova caught soon after explosion.  The spectrum, heavily
contaminated by the parent galaxy, seems dominated by a relatively red
continuum with overimposed H-beta with a P-Cyg profile, and H-alpha with a
complex profile consisting of three emission components:  a narrow
unresolved one, an intermediate (FWHM about 2500 km/s) one, and a broad
one (FWHM about 9500 km/s).  The He I 587.6-nm emission is also present.
An interstellar Na I D absorption feature is visible in the host-galaxy
rest frame with an equivalent width of about 0.6 nm.  Adopting the
recession velocity of 5945 km/s (as measured from the Na I D absorption)
for the parent galaxy, the expansion velocity derived from the H-beta
minimum is about 4500 km/s.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2006 CBAT
2006 September 26                (CBET 647)               Daniel W. E. Green