The circumburst density profile around GRB progenitors: a statistical study
نویسندگان
چکیده
منابع مشابه
GRB blastwaves through wind-shaped circumburst media
Context. A significant fraction of progenitors for long gamma-ray bursts (GRBs) are believed to be massive stars. The investigation of long GRBs therefore requires modeling the propagation of ultra-relativistic blastwaves through the circumburst medium surrounding massive stars. We simulate the expansion of an isotropic, adiabatic relativistic fireball into the wind-shaped medium around a massi...
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Aims. We report a multi-wavelength analysis of the prompt emission and early afterglow of GRB 051111 and discuss its properties in the context of current fireball models. Methods. The detection of GRB 051111 by the Burst Alert Telescope on-board Swift triggered early BVRi' observations with the 2-m robotic Faulkes Telescope North in Hawaii, as well as X-ray observations with the Swift X-Ray Tel...
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Using stellar binary population synthesis code we calculate the production rates and lifetimes of several types of possible GRB progenitors. We consider mergers of double neutron stars, black hole neutron stars, black hole white dwarfs and helium star mergers. We calibrate the results with the measured star formation rate history. We discuss the viability of each GRB model, and alternatively as...
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— The study and knowledge of the environment of Gamma-Ray Bursts is of great interest from many points of view. For high redshift (z > 0.5) events, the structure of the ambient medium is one of the best indicators of the nature and properties of the progenitor. It also tells us about the last stages of the pre-explosion evolution of the progenitor. In addition, it is interesting in its own as a...
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ژورنال
عنوان ژورنال: Astronomy & Astrophysics
سال: 2010
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361/201015581