GCN Circular 336
Subject
optical observation of the X-ray/GRB transient SAX J0835.9+5118
Date
1999-05-21T00:01:04Z (25 years ago)
From
Alberto Castro-Tirado at LAEFF-INTA <ajct@laeff.esa.es>
Optical report: observation of the SAX J0835.9+5118 field
A. Castro-Tirado (LAEFF-INTA Madrid and IAA-CSIC Granada), J. Greiner
(AIP Potsdam), S. Phleps (MPIA Heidelberg), E. Pian (ITESRE Bologna)
and E. Costa (IAS Frascati) report on behalf of a larger collaboration:
"We have obtained two 20-minute R-band exposures of the 1SAX J0835.9
+5118 error box (Gandolfi et al. IAUC 7174) starting at 19:18 UT
20 May 1999 (17.25 hours after the trigger) with the 2.2 m telescope
at the German-Spanish Calar Alto Observatory (CAHA). After a visual
comparison with the the Digital Sky Survey, no new sources were seen to
the DSS-2 limit. At the position of the radiosource reported by Frail
et al. (GCN 334) we see a point-like, faint object which is also present
in the DSS-2, as pointed out by Bloom et al. (GCN 335). This object does
not seem to have changed significantly in brightness.
Our frames reach significantly deeper than the DSS-2 image. If the
above-mentioned radiosource is not the counterpart to the SAX source,
a more detailed analysis and comparison with deeper images in the next
few days might yield a counterpart."