GRB afterglows: from ultra-relativistic to non-relativistic phase
نویسنده
چکیده
Postburst evolution of adiabatic fireballs that produce γ-ray bursts is studied. Emphasis has been put on the transition from the highly relativistic phase to the non-relativistic phase, which, according to our calculation, should happen much earlier than previously expected. The theoretical light curves decline a little sharper at the nonrelativistic stage than at early times, but still can fit the observations well. However, disagreements are obvious when t ≥ 100 d, implying a large initial energy E0, a low interstellar density n, or the possible existence of a persistent energy source at the center of the fireball.
منابع مشابه
ar X iv : a st ro - p h / 99 10 49 3 v 1 2 7 O ct 1 99 9 Overall Evolution of Jetted Gamma - ray Burst Ejecta
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Postburst evolution of adiabatic fireballs that produce γ-ray bursts is studied. Emphasis has been put on the transition from the highly relativistic phase to the non-relativistic phase, which, according to our calculation, should happen much earlier than previously expected. The theoretical light curves decline a little sharper at the non-relativistic stage than at early times, but still can f...
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