GRB 011121: A Collimated Outflow into Wind‐blown Surroundings
GRB 011121: A Collimated Outflow into Wind‐blown Surroundings
We report optical and near-infrared follow-up observations of GRB 011121 collected predominantly at ESO telescopes in Chile. We discover a break in the afterglow light curve after 1.3 days, which implies an initial jet opening angle of about 9°. The jet origin of this break is supported by the fact …