Properties of Gamma-Ray Burst Progenitor Stars

Abstract

We determine some basic properties of stars that produce spectacular gamma-ray bursts at the end of their life. We assume that accretion of the outer portion of the stellar core by a central black hole fuels the prompt emission, and that fall-back and accretion of the stellar envelope later produces the plateau in the X-ray light curve seen in some bursts. Using X-ray data for three bursts we estimate the radius of the stellar core to be ~ 1-3 x 10^10 cm, and that of the stellar envelope to be ~ 1-2 x 10^11 cm. The density profile in the envelope is fairly shallow, with ρ~ r^-2. The rotation speeds of the core and envelope are ~ 0.05 and ~ 0.2 of the local Keplerian speed, respectively.

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References in corpus (1)

• A Comprehensive Analysis of the Swift/XRT Data: II. Diverse Physical Origins of the Shallow Decay Segment

Cited by in corpus (6)

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• On the Implications of Late Internal Dissipation for Shallow-Decay Afterglow Emission and Associated High-Energy Gamma-Ray Signals
• X-Ray Flares of Gamma-Ray Bursts: Quakes of Solid Quark Stars?
• Non-thermal transient sources from rotating black holes