{
  "bibcode": "2002GCN..1419....1G",
  "body": "J. Gorosabel* (IAA-CSIC Granada), J. Hjorth, P. Jakobsson, J. Rasmussen, \nB. L. Jensen, H. Pedersen (Univ. of Copenhagen), J. M. Castro Ceron* \n(ROA San Fernando), A. Hornstrup (DSRI Copenhagen), A.O. Jaunsen (ESO Paranal),\nM. Weidinger, J. Fynbo* (IFA Aarhus), M. I. Andersen (Univ. of Oulu),\nP. Moller  (ESO Garching), S. Holland (Univ. of Notre Dame),\nA. J. Castro-Tirado (IAA-CSIC Granada), E. Pian (INAF, OA Trieste),\nA. Fruchter (STScI, Baltimore), J. Greiner (MPE Garching and AI Potsdam),\nL. Kaper, E. van den Heuvel (Univ. of Amsterdam), on behalf of the GRACE \ncollaboration, report:\n\nWe summarise the results of an optical and near-infrared search for the\nafterglow of GRB 020418 carried out with the 1.54-m Danish Telescope and \nthe 3.58-m New Technology Telescope, both at ESO's La Silla observatory.\n\nThe log of the observations is displayed in the following table:\n\n =========================================================================\n       Date UT       Filter ExpTime Telescope   Seeing Time since Error box\n       2002                   (s)  (+Instrument) (\")   GRB (days) Coverage (%)\n --------------------------------------------------------------------------\n April 19.9435--20.0066 Ks  45x60 3.58NTT(+SOFI) 0.65    1.6150    60**\n April 19.9445--19.9935 J   20x60 3.58NTT(+SOFI) 0.65    1.6089    60**\n April 19.9760--20.0507 R  10x420 1.54D(+DFOSC)  1.05    1.6532    100\n April 20.9541--21.0177 Ks  45x60 3.58NTT(+SOFI) 0.70    2.6258    60**\n April 20.9551--21.0052 J   20x60 3.58NTT(+SOFI) 0.70    2.6200    60**\n April 20.9720--21.0340 R   6x500 1.54D(+DFOSC)  0.90    2.6429    100\n June  01.9642--02.0267 R   9x500 1.54D(+DFOSC)  1.90   44.6353    100\n June  02.9592--03.0155 R   8x500 1.54D(+DFOSC)  1.40   45.6273    100\n --------------------------------------------------------------------------\n ** Central part\n ==========================================================================\n\nComparison of the images reveals no variable source contained in the error\nbox brighter than R = 23.0. Correcting for the effect of the Galactic \nextinction, the R-band upper limit corresponds to R = 22.3. \n\nFor the central part of the error box (the 60% of the error box covered for \nSOFI) we can set limits of Ks >= 21.0, J >= 22.6 and R >= 22.3 for any \nvariable source (magnitudes corrected for Galactic reddening).\n\nWe acknowledge the assistance of L. Vanzi at La Silla.\n\n---------------------------------------------------------------------------\n* Visiting the Astronomical Observatory of the University of Copenhagen.",
  "circularId": 1419,
  "createdOn": 1023511785000,
  "email": "jgu@laeff.esa.es",
  "subject": "GRB 020418, optical/near-IR observations",
  "submitter": "Javier Gorosabel at LAEFF-INTA, Madrid  <jgu@laeff.esa.es>",
  "eventId": "GRB 020418"
}