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GCN Circular 262

Optical Observations of GRB990217
1999-02-19T18:06:55Z (25 years ago)
Elena Pian at ITESRE-CNR,Bologna <>
GRB 990217 B and R band observations

E. Palazzi, N. Masetti, E. Pian, F. Frontera (ITESRE-CNR, Bologna),
P.M. Vreeswijk, E. Rol, T.J. Galama, G. Dubus (U. of Amsterdam),
J. van Paradijs (U. of Amsterdam and U. of Alabama in Huntsville),
C. Kouveliotou (NASA-MSFC/USRA), O. Hainaut (ESO), C. Tinney (AAT),
T. Axelrod, B.  Schmidt, and H. Jones (MSSSO), on behalf of a large
collaboration, report:

"Images of the GRB 990217 error box (Tarei et al. 1999, IAU Circ. 7110) 
were acquired on 1999 Feb 17.50 UT at Siding Spring with the 40-inch
telescope (R band), on Feb 17.48 at Mount Stromlo with the 74-inch
telescope (R), on Feb 17.54 with the 50-inch telescope (B and R), on Feb
18.03-18.07 and Feb 19.04-19.12 at ESO-La Silla with NTT+EMMI (B and R). 
Limiting magnitudes were R~22.5 for the 40-inch, B~20 and R~21 for the
50-inch, R~22 for the 74-inch, B~24.5 and R~24.5 for NTT on Feb 18, and
B~24 and R~23.5 for NTT on Feb 19. 

Comparison between the NTT images of Feb 18 and 19 shows no object varying
by more than 0.3 magnitudes down to R~23.5 and B~24 within the error box in
either band. Similarly, the comparison between the 40-inch and the Feb 18
NTT R band images shows no object varying by more than 0.3 magnitudes down
to R~22.5 within the error box.

This message can be cited."
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