{
  "bibcode": "1999GCN...272....1W",
  "body": "G. Williams, H. Park and R. Porrata report on behalf of the LOTIS \ncollaboration:\n\nLOTIS and Super-LOTIS obtained early time observations \nof the error box of GRB 990308 (BATSE Trig. 7457).\nThis event was detected and localized by the \nXTE/All-Sky Monitor.  LOTIS began imaging the area \ncentered on the 'Original' GCN coordinates 12.6 s after \nthe start of the burst.  Five images (10 s integration) \nwere obtained at these coordinates before the system \nreceived and responded to the 'Final' GCN coordinates. \nLOTIS began imaging the area centered on the 'Final' \nGCN coordinates 132.1 s after the start of the burst.  \n\nThe first five LOTIS images covered a small portion of \nthe XTE/ASM error box within, but near the edge of the \npreliminary BATSE 3-sigma error circle.  We matched all \nstellar objects in the error box with known Guide Star \nCatalogue objects.  No transient sources brighter than \nm ~ 11.5 (no filter) were detected.  Wispy high clouds \nreduced the system's limiting magnitude during this event.\n\nLOTIS slewed to the more accurate 'Final' GCN coordinates \n132.1 s after the start of the burst. The subsequent images \ncovered the entire XTE/ASM error box within the \nBATSE 2-sigma error circle.  We found a single anomalous \nconstant source within the error box with a position which \ncorresponds to the position of a V ~ 10.6 asteroid (Laetitia)\nat the time of the image.  All other sources within the \nXTE/ASM error box correspond to known stars in the GSC.\nNo fading or flaring objects brighter than m ~ 11.0 were \nfound.\n\nIn addition, Super-LOTIS (60 cm reflector) began a raster \nscan around the 'LOCBURST' GCN coordinates 1700 s after \nthe start of the burst. Four Super-LOTIS images \n(30 s integration; t=1694 s, 1809 s, 2620 s, 3923 s)\ncovered most of the XTE/ASM error box within the BATSE 2-sigma \nerror circle.  No fading or flaring objects brighter than \nm ~ 14.0 (no filter) were detected in the Super-LOTIS images.\nSuper-LOTIS is presently operating at a temporary site \nat LLNL utilizing an uncooled prototype CCD camera. \nThin clouds and surrounding building lights prevented \nthe system from reaching a deeper limiting magnitude.\n\nFurther details of the LOTIS timing and coverage as well \nas images are posted at: \n\nhttp://hubcap.clemson.edu/~ggwilli/LOTIS/GRB990308.html\n\nThis message is citable.",
  "circularId": 272,
  "createdOn": 921066681000,
  "email": "ggwilli@hubcap.clemson.edu",
  "subject": "GRB990308 (Trig. 7457), optical observations",
  "submitter": "Grant Williams at Clemson  <ggwilli@hubcap.clemson.edu>",
  "eventId": "GRB 990308"
}