Circular No. 8102
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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SUPERNOVA 2003co
     Further to IAUC 8101, W. M. Wood-Vasey, G. Aldering, and P.
Nugent report the discovery of an apparent supernova (mag 18.6) on
unfiltered Palomar NEAT images taken on Mar. 22.14, 22.16, and
22.18 UT.  The new object is located at R.A. = 10h49m39s.91, Decl.
= +29o21'44".6 (equinox 2000.0), which is 7".4 west and 7".9 south
of the center of the apparent host galaxy.  Additional magnitudes
of SN 2003co from NEAT images:  2002 Mar. 31.32, [20.9; 2003 Feb.
21.46, [20.9; Mar. 30.14, 18.1.


XTE J1550-564
     P. Woudt, University of Cape Town (UCT); and P. Charles and
I. C. Shih, University of Southampton, report that, following the
INTEGRAL detection of renewed hard x-ray activity in the blackhole
transient XTE J1550-564 (cf. IAUC 8100), they obtained high-speed
photometry of the optical counterpart (Jain et al. 2001, Ap.J. 554,
L181) with the South African Astronomical Observatory 1.9-m
telescope (+ UCT CCD) during 25 min on Mar. 27.  The object
appeared at V about 18 (close to its maximum during the 2000
outburst) and it displays significant variability on timescales of
1-2 min, including a flare of about 0.5 mag lasting < 20 s.
Further infrared and radio observations of this microquasar are
encouraged.


GRB 030329
     J. E. McGaha, Tucson, AZ, reports that CCD images taken with a
0.30-m f/10 Schmidt-Cassegrain reflector show an object at R.A. =
10h44m50s.01, Decl. = +21o31'17".8 (equinox 2000.0) that faded from
red mag 16.2 on Mar. 31.201 UT to 16.4 on Mar. 31.289.  Nothing is
visible at this location on a Digitized Sky Survey plate taken in
1996 (limiting mag about 20.5).


SUPERNOVA 2003cn IN IC 849
     M. Hamuy, Carnegie Observatories, reports that a spectrum
(range 380-730 nm) of SN 2003cn (cf. IAUC 8101), obtained on Mar.
31.31 UT with the Las Campanas Dupont 2.5-m telescope, shows that
this is a type-II supernova characterized by Balmer lines
exhibiting P-Cyg profiles, although the absorption component of
H_alpha is very weak.  The expansion velocity of 5900 km/s, derived
from the minimum of H_beta (assuming the NED recession velocity of
5430 km/s for the host galaxy), and the weak He I 587.6-nm line
suggest that SN 2003cn is about 2-3 weeks old.

                      (C) Copyright 2003 CBAT
2003 March 31                  (8102)            Daniel W. E. Green