Electronic Telegram No. 485
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 2006bt
     Further to IAUC 8693, E. Lee and W. Li report the LOSS discovery of an
apparent supernova on unfiltered KAIT images taken on Apr. 26.48 (at mag
17.5) and 27.36 UT (mag 17.4).  SN 2006bt is located at R.A. = 15h56m30s.53,
Decl.= +20o02'45".6 (equinox 2000.0).  The new object lies between CGCG
108-013 and another galaxy, and is 44".4 west and 22".9 south of the nucleus
of CGCG 108-013.  A KAIT image taken on Feb. 24.51 showed nothing at this
position (limiting mag about 19.0).
     A. V. Filippenko and R. J. Foley (University of California, Berkeley)
report that inspection of a high-quality CCD spectrum (range 320-920 nm),
obtained on Apr. 27 UT with the Keck I 10-m telescope (+ LRIS), shows that
2006bt is a type-Ia supernova, probably before maximum brightness.  The
expansion velocity derived from the Si II 615-nm absorption line is about
12000 km/s, but the spectrum also exhibits low-velocity structure.  The
emission component of the Ca II H and K P-Cygni line is unusually strong.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2006 CBAT
2006 April 27                    (CBET 485)               Daniel W. E. Green