Models for the Circumstellar Medium of Long Gamma-Ray Burst Progenitor Candidates
We present hydrodynamical models of circumstellar medium (CSM) of long gamma-ray burst (GRB) progenitorcandidates. These are massive stars that have lost a large amount of mass in the form of stellar wind duringtheir evolution.There are two possible ways to probe the CSM of long GRB progenitors. Fir...
| Autores: | , , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2007 |
| País: | México |
| Institución: | Universidad Nacional Autónoma de México |
| Repositorio: | Redalyc-UNAM |
| OAI Identifier: | oai:redalyc.org:57130002 |
| Acceso en línea: | https://www.redalyc.org/articulo.oa?id=57130002 |
| Access Level: | acceso abierto |
| Palabra clave: | Física, Astronomía y Matemáticas RAYET OUTFLOWS STARS: WOLF STARS: WINDS HYDRODYNAMICS |
| Sumario: | We present hydrodynamical models of circumstellar medium (CSM) of long gamma-ray burst (GRB) progenitorcandidates. These are massive stars that have lost a large amount of mass in the form of stellar wind duringtheir evolution.There are two possible ways to probe the CSM of long GRB progenitors. Firstly, the GRB afterglowconsists of synchrotron radiation, emitted when the GRB jet sweeps up the surrounding medium. Therefore,the lightcurve is directly related to the density prole of the CSM. The density can either decrease with theradius squared (as is the case for a freely expanding stellar wind) or be constant (as we would expect for shockedwind or the interstellar medium). Secondly, material between the GRB and the observer will absorb part ofthe afterglow radiation, causing absorption lines in the afterglow spectrum. In some cases, such absorptionlines are blue-shifted relative to the source indicating that the material is moving away from the progenitorstar. This can be explained in terms of wind interactions in the CSM. We can use the CSM of these stars toinvestigate their prior evolutionary stage |
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