Decay of the GRB 990123 Optical Afterglow: Implications for the Fireball Model

Hjorth, Jens; Walter, Fabian; Hippelein, Hans; Zhang, Haotong; Chen, Jiansheng; Piro, Luigi; Greiner, Jochen; Courbin, Frederic; Pian, Elena; Hudec, Rene; Pedersen, Holger; Heise, John; Castro-Tirado, Alberto J.; Costa, Enrico; Masetti, Nicola; Wei, Jianyan; Sagar, Ram; Frontera, Filippo; Palazzi, Eliana; Rhoads, James E.; Caon, Nicola; Pandey, Anil K.; Rector, Travis A.; Claver, Charles F.; Andersen, Michael I.; Jakobsson, Pall; Oscoz, Alejandro; Gorosabel, Javier; Burud, Ingunn; Aceituno, Jesus; Pedraz, Santos; Zapatero-Osorio, Maria Rosa; Cairos, Luz Marina; Bartolini, Corrado; Guarnieri, Adriano; Piccioni, Adalberto; Mohan, Vinay; Yadav, Ramakant K. S.; Nilakshi, Nilakshi; Bjornsson, Gunnlaugur; Valentini, Gaetano; Piersimoni, Anna; Montoya, Luz Maria; Gredel, Roland; Ott, Jorgen; Sanchez-Bejar, Victor; Gutierrez, Carlos; Zhu, Jin; Zhou, Aiying; Guziy, Sergei; Shlyapnikov, Aleksei; Feroci, Marco