NUOVO CIMENTO DELLA SOCIETA ITALIANA DI FISICA B-BASIC TOPICS IN PHYSICS, cilt.121, sa.12, ss.1471-1473, 2006 (SCI-Expanded)
Swift unprecedented fast follow-up observations of gamma-ray bursts have allowed us to discover a new feature of GRB afterglows: a phase of shallow decay, usually attributed to energy injection in the burst ejecta, which can last for several thousands of seconds both in the X-ray and optical bands. Here I discuss this phase in the case of Swift GRBs 050401, 050801 and 050802.