GCN Circular 416
Subject
GRB 990915 optical observations
Date
1999-09-26T09:13:19Z (25 years ago)
From
Alberto Castro-Tirado at LAEFF-INTA <ajct@laeff.esa.es>
GRB 990915, optical observations
---------------------------------
Alberto Castro-Tirado, LAEFF-INTA (Madrid) and IAA-CSIC (Granada)
on behalf of a large collaboration:
Victor Costa and Jose L. Ortiz, IAA-CSIC
Oliver Cordes, Martin Altmann and Daniel Harbeck, Univ. of Bonn
Javier Gorosabel, LAEFF-INTA
Mara Salvato and Jochen Greiner, AIP (Potsdam)
Kevin Hurley, UCBerkeley/SSL
reports:
"Following the detection of the strong burst GRB 990915
by BATSE and COMPTEL (Batse trigger # 7766) we have obtained:
-150 frames (60-s, no filter, 20' x 13' FOV) at the 0.8-m
Schmidt telescope of the German-Spanish Calar Alto Observatory
(CAHA) starting 0.5 hr after the burst. The frames covered a
significant fraction of the Hunstville/Locburst and COMPTEL
error boxes and about a 15 % of the NEAR error box given by
Hurley et al. in GCN 412.
-25 frames (60-s, R-band, 16' x 16' FOV) at the 1.23-m CAHA
telescope starting 30 hr after the burst. The frames covered an
additional fraction (65 %) of the NEAR error box.
-10 frames (150-s, R-band) at the 1.23-m CAHA telescope starting
50 hr after the burst. The frames covered the rest (20 %) of
the NEAR error box.
After a careful visual comparison with the Digital Sky Survey,
I have not found any source varying more than 0.3 mag when comparing
to the DSS-1 charts, i.e. a limit of R > 20.5 can be imposed to the
GRB 990915 optical afterglow."