TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  168
SUBJECT: GRB 981220, radio observations
DATE:    98/12/24 18:48:32 GMT
FROM:    Titus Galama at U.Amsterdam  <titus@astro.uva.nl>

T.J. Galama, P. Vreeswijk (U. of Amsterdam), J. van Paradijs (U. of
Amsterdam and U. of Alabama in Huntsville), C. Kouveliotou
(USRA/MSFC), R. Strom (NFRA and U. of Amsterdam), G. de Bruyn (NFRA
and U. of Groningen) report:

"We have observed the error box of GRB 981220 (Smith et al. 1998, GCN
Circ 159; Hurley et al. 1998, GCN Circ 160) with the Westerbork Radio
Synthesis Telescope (WSRT). We observed for 7 hours switching between
4.88 and 1.38 GHz on Dec 22.98 UT, 1998, and for 12 hours at 4.88 GHz
on Dec 23.88 UT, 1998. We find no sources in the errorbox at 1.38 GHz
down to 200 microJy (4 sigma).  At RA = 3h42m28.98s +- 0.07s, Dec =
+17d09'14.7'' +- 1.6'', we detect a source at 4.88 GHz at 260 +- 90
microJy (Dec 22.98), which is not detected at 1.38 GHz. On Dec 23.88
we measure 200 +- 50 microJy (4.88 GHz). The location of the source is
at the edge of the error box of GRB 981220. Whether or not this source
is related to GRB 981220 is unclear. We will continue monitoring the
error box at 4.88 GHz."

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