Decay of the GRB 990123 optical afterglow: implications for the fireball model |
| |
Authors: | Castro-Tirado Zapatero-Osorio Caon Cairos Hjorth Pedersen Andersen Gorosabel Bartolini Guarnieri Piccioni Frontera Masetti Palazzi Pian Greiner Hudec Sagar Pandey Mohan Yadav Nilakshi Bjornsson Jakobsson Burud et |
| |
Institution: | Instituto de Astrofisica de Andalucia, IAA-CSIC, Granada, Spain. Instituto de Astrofisica de Canarias, La Laguna, Tenerife, Spain. Astronomical Observatory, University of Copenhagen, Copenhagen, Denmark. Nordic Optical Telescope, La Palma, T. |
| |
Abstract: | Broad-band (ultraviolet to near-infrared) observations of the intense gamma ray burst GRB 990123 started approximately 8.5 hours after the event and continued until 18 February 1999. When combined with other data, in particular from the Robotic Telescope and Transient Source Experiment (ROTSE) and the Hubble Space Telescope (HST), evidence emerges for a smoothly declining light curve, suggesting some color dependence that could be related to a cooling break passing the ultraviolet-optical band at about 1 day after the high-energy event. The steeper decline rate seen after 1.5 to 2 days may be evidence for a collimated jet pointing toward the observer. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|