NUTTelA-TAO observations of GRB201015A

We have successfully observed GRB 201015A starting only 58 seconds after the BAT trigger, measuring in three Sloan filter bands, g’, r’, and i’(GCN 28674).

The GRB201015A optical light curve shows three main time periods of early afterglow: peak phase, post-peak phase, and middle phase. The source rises to 17.3, 16.8 and 16.3 in g’, r’, and i’ filters (without reddening corrections), respectively, during the first 300 s, and then fades as a power law, t^−α, with two different decay indices in two different intervals 500∼ 1600 (α1=1.2) and 1900∼ 4000 s (α2=0.8).