title: Prompt Optical Observations of Gamma-Ray Bursts.
abstract: The Robotic Optical Transient Search Experiment (ROTSE) seeks to measure simultaneous and early afterglow optical emission from gamma-ray bursts (GRBs). A search for optical counterparts to six GRBs with localization errors of 1 deg2 or better produced no detections. The earliest limiting sensitivity is mROTSE>13.1 at 10.85 s (5 s exposure) after the gamma-ray rise, and the best limit is mROTSE>16.0 at 62 minutes (897 s exposure). These are the most stringent limits obtained for the GRB optical counterpart brightness in the first hour after the burst. Consideration of the gamma-ray fluence and peak flux for these bursts and for GRB 990123 indicates that there is not a strong positive correlation between optical flux and gamma-ray emission.
authors.initials: C
authors.lastname: Akerlof
authors.initials: R
authors.lastname: Balsano
authors.initials: S
authors.lastname: Barthelmy
authors.initials: J
authors.lastname: Bloch
authors.initials: P
authors.lastname: Butterworth
authors.initials: D
authors.lastname: Casperson
authors.initials: T
authors.lastname: Cline
authors.initials: S
authors.lastname: Fletcher
authors.initials: F
authors.lastname: Frontera
authors.initials: G
authors.lastname: Gisler
authors.initials: J
authors.lastname: Heise
authors.initials: J
authors.lastname: Hills
authors.initials: K
authors.lastname: Hurley
authors.initials: R
authors.lastname: Kehoe
authors.initials: B
authors.lastname: Lee
authors.initials: S
authors.lastname: Marshall
authors.initials: T
authors.lastname: McKay
authors.initials: A
authors.lastname: Pawl
authors.initials: L
authors.lastname: Piro
authors.initials: J
authors.lastname: Szymanski
authors.initials: J
authors.lastname: Wren