{
  "bibcode": "2002GCN..1614....1K",
  "body": "A. Klotz and M. Boer, CESR/CNRS (Centre d'Etude Spatiale des\nRayonnements, Toulouse, France) report measurements obtained by members\nof the AUDE network (Association des Utilisateurs de Detecteurs\nElectroniques). As images were not filtered, the authors computed the\nmagnitudes in reference to the R band system which is expected to be the\nmost reliable for unfiltered CCD images. \n\nMagnitudes of GRB 021004 : \n\n2002 oct. 5, 01h04 UT : R=18.8 by R. Poncy (1) \n2002 oct. 5, 22h30 UT : R=19.70 +/- 0.1 (referenced to USNO) by P.\nMartinez & P.M. Berger (2) \n\n(1) Diam. 254 mm \n    Integ. 30 x 60 sec. \n    Location : Le Cres, France (IAU station 177)\n\n(2) Diam. 820 mm \n    Integ. 23 x 60 sec. \n    Location : ADAGIO observatory, Belesta, France (IAU station A05) \n\nNote also a detection of the optical counterpart at 2002 oct. 5, 21h30\nUT, by A. Klotz using a telescope of only 200 mm diameter. Low signal to\nnoise did not allow to measure the magnitude, but the limiting magnitude\nof the image is about 20.5 (addition of 60 frames of 60 sec). This\ndemonstrates that small telescopes can detect the afterglow of a GRB\neven 1.4 days after the GRB event.\n\nImages are available at the following URL:\nhttp://www.cesr.fr/~klotz/grb021004/aude.html\n\nThese data are coherent with already reported magnitude in other\ncirculars, and fill some gaps in the light curve.",
  "circularId": 1614,
  "createdOn": 1034234180000,
  "email": "Michel.Boer@cesr.fr",
  "subject": "GRB 021004: Optical observations, AUDE network",
  "submitter": "Michel Boer at CESR-CNRS  <Michel.Boer@cesr.fr>",
  "eventId": "GRB 021004"
}