GCN Circular 2817
Subject
GRB 041016:Optical limit during first minute
Date
2004-10-16T21:23:11Z (20 years ago)
From
Tom Vestrand at LANL <vestrand@lanl.gov>
J. Wren, W.T. Vestrand, P. Wozniak, R. White, report on behalf of the
RAPTOR team.
Stereoscopic observations collected by the RAPTOR wide-field sky monitoring
systems allow us to place optical limits on a prompt optical flash from GRB
041016 (HETE trigger 3578). The earliest images were 10 second exposures
obtained starting at 04:40:13.3 UT (35 seconds after the GRB trigger) with
a limiting magnitude of R ~ 13.1 mag. When compared to our later follow-up
images and sky patrol images taken earlier in the evening, no new or
variable objects were detected (other than known
asteroids). Straightforward extrapolation of the light curve for prompt
optical emission measured from GRB 021211, an event with approximately half
the 25-300 keV fluence of GRB 041016, predicts an optical flux that exceeds
these early flux limits.