Early Observations of the Afterglow of GRB000301c
نویسنده
چکیده
We report multiband observations of the Optical Transient (OT) associated with GRB000301c carried out between 2–4 March 2000 using the 2.34-m Vainu Bappu Telescope (VBT) at Kavalur, India. When combined with other reported data, the initial decline in the R-band magnitude with log (t − t0), the time since the burst is fit with a slope α1 = -0.70 ± 0.07 which steepens after about 6.0 days to a slope of α2 = -2.44 ± 0.29. This change in slope does not occur smoothly but there is an indication for a bimodal distribution. The available measurements of the evolution of (B–R) color do not show any discernible evolution in the first 12 days. Subject headings: cosmology : observations – gamma rays: bursts.
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