The Surroundings of Gamma-Ray Bursts: Constraints on Progenitors

Roger A. Chevalier

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arXiv · astro-ph/0309637

The Surroundings of Gamma-Ray Bursts: Constraints on Progenitors

Roger A. Chevalier

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Abstract

The association of a supernova with a gamma-ray burst (GRB 030329) implies a massive star progenitor, which is expected to have an environment formed by pre-burst stellar winds. Although some sources are consistent with the expected wind environment, many are not, being better fit by a uniform density environment. One possibility is that this is a shocked wind, close to the burst because of a high interstellar pressure and a low mass loss density. Alternatively, there is more than one kind of burst progenitor, some of which interact directly with the interstellar medium. Another proposed environment is a pulsar wind bubble that has expanded inside a supernova, which requires that the supernova precede the burst.

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Roger A. Chevalier. 2003-09-23. The Surroundings of Gamma-Ray Bursts: Constraints on Progenitors. https://arxiv.org/abs/astro-ph/0309637

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