TITLE:   GCN CIRCULAR
NUMBER:  735
SUBJECT: GRB 000623, optical observations
DATE:    00/06/30 16:15:09 GMT
FROM:    Javier Gorosabel at LAEFF-INTA, Madrid  <jgu@laeff.esa.es>

J. Gorosabel (DSRI, Copenhagen),
S. Pascual, J. Gallego, J. Zamorano (UCM, Madrid),
A.J. Castro-Tirado (LAEFF-INTA, Madrid, and IAA-CSIC, Granada),
J.M. Castro Ceron (ROA, San Fernando),
S. Klose (Thueringer Landessternwarte, Tautenburg), 
J. Greiner (AIP, Potsdam),

report on behalf of a larger European collaboration:

"R-band images covering 90%  of the GRB  000623 error  box
 (GCN #730) were  acquired with the  2.2-m CAHA telescope,
 as follows:

    Date(UT)        T-T0(hr)   Exp.(s)   Seeing(")  Lim. Mag.
 ------------------------------------------------------------
  24.900 -- 24.908   29.1       120        1.2"       20
  27.860 -- 27.876  100.2       240        2.0"       20
 ------------------------------------------------------------

 Comparison between these two epoch observations did not reveal
 any object brighter than R ~ 19.7 showing a variation larger
 than 0.3 mag."

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