Early re-brightening of the afterglow of GRB 050525a

We present time resolved optical data acquired by the TAROT automated observatory on the afterglow of GRB 050525a from 6 to 136 minutes after the GRB. We evidence a rapid re-brightening of 0.65 magnitude of the afterglow at $\\sim$ 33 min after the GRB. The decay slope $\\alpha$ is $1.14\\pm 0.07$ in the first part and is $1.23\\pm 0.27$ after the re-brightening event. The afterglow of GRB 050525a is the third known afterglow that exhibits a re-brightening event begining at 0.01--0.02 day in the rest time frame.

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