{
  "bibcode": "2000GCN...633....1H",
  "body": "A. Henden (USRA/USNO), C. Luginbuhl (USNO),\nB. Canzian (USNO) on behalf of the USNO GRB Team,\nVijay Mohan, S. B. Pandey and Ram Sagar, UPSO (Nainital),\nDavid Alcalde and David Martinez-Delgado, IAC (Tenerife),\nJose Maria Castro Ceron, ROA (San Fernando),\nAlberto Castro-Tirado,\n     LAEFF-INTA (Madrid) and IAA-CSIC (Granada),\nand Javier Gorosabel Urkia, DSRI report:\n\nWe have observed the entire preliminary IPN\nerror box for GRB 000408 (GCN#626) as well\nas the refined error box (GCN#632)\nfrom several sites and on both available nights.\nBecause of the shape of the error box, mosaics were\nused at each site, limiting the depth of exposure\nfor any particular field.  Only R-band observations\nwere made.  A log of the observations is given below.\n\nTEL.       MARCH (UT)      TEXP   RA      DEC    \n--------------------------------------------------\nIAC80   8.9352 --  9.0103  3800 9:10:41 +66:34:15\nIAC80   9.0094 --  9.0140   200 9:09:39 +66:34:15\nIAC80   9.0141 --  9.0187   200 9:08:39 +66:34:47\nIAC80   9.0176 --  9.0223   200 9:07:42 +66:35:15\nIAC80   9.0210 --  9.0257   200 9:06:41 +66:35:47\nIAC80   9.0248 --  9.0294   200 9:11:41 +66:34:50\nIAC80   9.0292 --  9.0338   200 9:12:40 +66:34:21\nIAC80   9.0327 --  9.0373   200 9:13:42 +66:33:52\nIAC80   9.0360 --  9.0407   200 9:14:41 +66:33:20\nIAC80   9.0360 --  9.0407   200 9:14:41 +66:33:20\nIAC80   9.9319 --  9.9741  3600 9:08:26 +66:33:28\nUPSO    9.7667 --  9.7724   500 9:48:41 +66:35:15\nUPSO    9.7764 --  9.7821   500 9:10:27 +66:35:08\nUSNO    9.136  --  9.225   1800 9:13:41 +66:33:51\nUSNO    9.128  --  9.216   1800 9:12:02 +66:33:51\nUSNO    9.121  --  9.209   1800 9:10:20 +66:33:51\nUSNO    9.145  --  9.233   1800 9:08:41 +66:33:51\nUSNO    9.153  --  9.241   1800 9:07:01 +66:33:51\nUSNO   10.154  -- 10.176   1800 9:13:41 +66:33:51\nUSNO   10.176  -- 10.198   1800 9:12:02 +66:33:51\nUSNO   10.130  -- 10.152   1800 9:10:20 +66:33:51\nUSNO   10.199  -- 10.229   1800 9:08:41 +66:33:51\nUSNO   10.229  -- 10.251   1800 9:07:01 +66:33:51\n\nPOSS-II/F for this field is not available through\nDSS.  However, it is available through the USNO\nPMM pixel database.  We have placed three files\non the anon ftp server that cover the error box:\nftp://ftp.nofs.navy.mil/pub/outgoing/aah/grb/grb000408-1.jpg\nftp://ftp.nofs.navy.mil/pub/outgoing/aah/grb/grb000408-2.jpg\nftp://ftp.nofs.navy.mil/pub/outgoing/aah/grb/grb000408-3.jpg\nin order of increasing RA.  A finder chart from POSS-I\nwith the refined error box marked on it is at:\nhttp://www.dsri.dk/~jgu/grb000408/grb000408.dss.gif\n\nNo candidate was found above the POSS-II plate limit.\nThe two deep exposure sets from USNO were blinked\nto look for transients below the POSS-II plate\nlimit.  While several candidates are present,\nnone is entirely convincing at a limiting\nmagnitude of approximately R=21.5.  However, for\ncompleteness, here are the two best candidates\ninside the error box, both R=20.5 or fainter:\nA  09:11:04.82  +66:33:31.3  J2000\nB  09:08:51.36  +66:33:36.5  J2000 \n\nPreliminary BVRI all-sky calibration of the central\npart of the error box can be found at\nftp://ftp.nofs.navy.mil/pub/outgoing/aah/grb/grb000408.dat\nThe external zero-point errors for this file are estimated\nto be +/- 0.05mag.  Refinement of this photometry\nwill be performed in late April if an OT is discovered.\n\nFurther data analysis is in progress.\n\n[GCN OPS NOTE (11 Apr 00):  The co-authors S.B.Pandey & David Martinez-Delgado\nwere added to the list.]",
  "circularId": 633,
  "createdOn": 955406676000,
  "email": "aah@nofs.navy.mil",
  "subject": "GRB 000408, optical observations",
  "submitter": "Arne A. Henden at USNO/USRA  <aah@nofs.navy.mil>",
  "eventId": "GRB 000408"
}