Circular No. 8061
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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SUPERNOVA 2003W IN UGC 5234
     Further to IAUC 8058, W. Li and D. Weisz report the LOTOSS
discovery of a supernova on unfiltered KAIT images taken on Jan.
28.4 (mag about 17.3) and 29.4 UT (mag about 16.9), confirmed on
Jan. 29.4 (mag about 17.0) with the Tenagra II telescope by M.
Schwartz.  SN 2003W is located at R.A. = 9h46m49s.48, Decl. =
+16o02'37".6 (equinox 2000.0), which is 0".3 west and 3".4 north of
the nucleus of UGC 5234.  A KAIT image taken on Jan. 16.4 showed
nothing at this position (limiting mag about 19.0).
     T. Matheson, P. Challis, and R. Kirshner, Harvard-Smithsonian
Center for Astrophysics, report that a spectrum (range 320-880 nm)
of SN 2003W, obtained by Matheson on Jan. 29.34 UT with the MMT
6.5-m telescope (+ Blue Channel spectrograph), shows it to be a
type-Ia supernova well before maximum.  The spectrum consists of a
blue continuum with well-defined Si II and Ca II features, similar
to that of SN 1994D at 12 days before maximum (Filippenko 1997,
ARAA 35, 309).  Adopting the NASA/IPAC Extragalactic Database (NED)
recession velocity of 6017 km/s for the host galaxy, the supernova
expansion velocity is 20200 km/s for Si II (rest 635.5 nm) and
27600 km/s for Ca II (rest 395.1 nm).  These expansion velocities
imply an age of approximately 2 weeks before maximum, based upon
comparison with values presented by Jha et al. (1999, Ap.J. Supp.
125, 73).


SUPERNOVA 2003U IN NGC 6365A
     Matheson et al. add that a spectrum (range 320-880 nm) of SN
2003U (cf. IAUC 8059), obtained as above on Jan. 29.53 UT, shows it
to be a type-Ia supernova.  Adopting the NED recession velocity of
8496 km/s for the host galaxy, the supernova expansion velocities
are 13300 km/s for Si II (rest 635.5 nm) and 19200 km/s for Ca II
(rest 395.1 nm).  The spectral-feature age of the supernova is 5
+/- 2 days before maximum light.


SUPERNOVA 2003L IN NGC 3506
     S. R. Kulkarni, California Institute of Technology, reports
that A. M. Soderberg, E. Berger, D. A. Frail, and he have observed
a bright, transient radio source at the optical position of SN
2003L (IAUC 8048) with the Very Large Array (fluxes: Jan. 26.23 UT,
1.4 +/- 0.03 mJy at 8.5 GHz; Jan. 28.22, 1.6 +/- 0.06 mJy at 8.5
GHz and 3.2 +/- 0.08 mJy at 22 GHz).  They comment:  "The radio
luminosity is high, being 20 percent that of SN 1998bw.
Alternatively, the circumstellar medium could be quite dense."

                      (C) Copyright 2003 CBAT
2003 January 29                (8061)            Daniel W. E. Green