Circular No. 6909
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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SUPERNOVA 1998cd IN ANONYMOUS GALAXY
     J. Mueller reports her discovery of an apparent supernova (mag
about 17.5) on a plate taken on May 17 with the 1.2-m Oschin
Schmidt Telescope in the course of the second Palomar Sky Survey.
R. Gal obtained a CCD frame on May 18 with the Palomar 1.5-m
telescope that confirms the presence of the object.  G. V.
Williams, Smithsonian Astrophysical Observatory, provides the
following reduction of positional measures by Mueller for SN 1998cd:
R.A. = 10h45m04s.16, Decl. = +39o25'12".5 (equinox 2000.0); this
corresponds to an offset 8".2 east and 5".8 south from the galaxy's
center.  The object does not appear on original Sky Survey prints
or on a IIIa-J Sky Survey plate taken on 1991 Feb. 9 by C. Brewer
and J. D. Mendenhall.


GRB 980515
     M. Feroci and L. Piro, Istituto Astrofisica Spaziale, CNR,
Rome; M. R. Daniele, G. Gennaro, S. Rebecchi, and G. Celidonio,
BeppoSAX Science Operation Center, Rome; L. A. Antonelli, BeppoSAX
Science Data Center, Rome; and J. Heise, Space Research
Organization of the Netherlands, Utrecht, report:  "The BeppoSAX
Wide Field Camera error box of GRB 980515 was observed with the
BeppoSAX Narrow Field Instruments (NFI) starting on May 16.1178 UT
(10 hr after the burst).  A previously unknown x-ray source, 1SAX
J2116.8-6712, was detected by the MECS instruments (units 2 and 3)
at R.A. = 21h16m49s, Decl. = -67o11'.8 (equinox 2000.0; preliminary
error radius 1'.5 due to the poor statistical quality).  This
position is 4'.9 from the centroid of the WFC position (GCN 73).
The source 1SAX J2116.8-6712 exhibits a moderate variability over
the two-day NFI observation.  There is no clear evidence for a
monotonic decaying behavior.  The average count rate was 0.0026 +/-
0.0006 count/s (2-10 keV) in the two MECS units, corresponding to
(1.6 +/- 0.4) x 10E-13 erg cmE-2 sE-1 (assuming a Crab-like energy
spectrum).  At this time, 1SAX J2116.8-6712 is the only candidate
for the x-ray afterglow of GRB 980515."


SUPERNOVA 1998aq IN NGC 3982
     CCD magnitude estimates, unfiltered unless otherwise noted:
May 7.862 UT, 12.9 (G. Masi, Ceccano, Italy); 8.915, V = 12.53 (D.
Hanzl, Brno, Czech Republic); 8.99, 12.8 (L. Boschini, Monte di
Nese, Bergamo, Italy); 9.898, 13.0 (Masi); 16.899, 13.3 (Masi).

                      (C) Copyright 1998 CBAT
1998 May 19                    (6909)            Daniel W. E. Green