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تسجيل مستخدم جديدReal-Time Optical Flux Limits From Gamma-Ray Bursts Measured By The GROCSE Experiment
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The Gamma-Ray Optical Counterpart Search Experiment (GROCSE) presents new experimental upper limits on the optical flux from gamma-ray bursts (GRBs). Our experiment consisted of a fully-automated very wide-field opto-electronic detection system that imaged locations of GRBs within a few seconds of receiving trigger signals provided by BATSEs real-time burst coordinate distribution network (BACODINE). The experiment acquired ~3800 observing hours, recording 22 gamma-ray burst triggers within $sim$30 s of the start of the burst event. Some of these bursts were imaged while gamma-ray radiation was being detected by BATSE. We identified no optical counterparts associated with gamma-ray bursts amongst these events at the m$_V$ $sim$ 7.0 to 8.5 sensitivity level. We find the ratio of the upper limit to the V-band optical flux, F$_ u$, to the gamma-ray fluence, $Phi_gamma$, from these data to be $2 times 10^{-18} < F_ u/Phi_gamma < 2 times 10^{-16}$.
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