An achromatic break in the afterglow of the short GRB 140903A: evidence for a narrow jet

E. Troja, T. Sakamoto, S. B. Cenko +17

We report the results of our observing campaign on GRB140903A, a nearby (z=0.351) short duration (T90~0.3 s) gamma-ray burst discovered by Swift. We monitored the X-ray afterglow w…