GCN Circular 19

H. S. Park*                                                             #019
on behalf of the LOTIS collaboration:
 
R. Bionta, E. Ables, L. Ott, E. Parker (LLNL)
G. Williams, D. Hartmann (Clemson University)
S. Barthelmy, P. Butterworth, N. Gehrels, T. Cline (NASA/GSFC)
C. Kouveliotou, J. Fishman, C. Meegan (NASA/MSFC)
D. Band (U.C. San Diego)
K. Hurley (U. C. Berkeley)
D. Ferguson (CalState, Hayward)
 
"LOTIS (the  Livermore Optical Transient Imaging System), an automated,
wide-field-of-view telescope system dedicated to the search for
simultaneous GRB optical counterparts, was on-line on the night of Dec. 27
when BATSE detected GRB971227.  LOTIS received GCN coordinates
derived from BATSE telemetry approximately 4 seconds after the start of
the burst and obtained its first 10 second exposure, centered on the GCN
coordinates 6 seconds later (10 sec after the burst began: 27.3495 UT)
LOTIS continued taking 10 second exposures at the rate of 1 image
every 20 seconds for the next 20 minutes, then at the rate of once per
minute for the rest of the night.  Because of LOTIS's large,
17.4 x 17.4 degree field of view, the recorded images fully contain
the error box of the location of the associated x-ray transient
detected by BeppoSAX's NFI despite the 6.7 degree difference
between the location of the BeppoSAX NFI position and the
GCN BATSE-Original coordinates.  A computer-aided visual examination
of the area within the BeppoSAX NFI/WFC position error circle (8' radius)
revealed 10 objects brighter than a visual magnitude of mV ~ 12.3 +/- 0.3;
all of which were identified with known objects in the Guide Star Catalog and
the Digital Sky Survey, and none showing variations in brightness.
Further analysis is in progress."
 
*hpark@llnl.gov