A turbulent model of gamma-ray burst variability
Abstract
A popular paradigm to explain the rapid temporal variability observed in gamma-ray burst (GRB) light curves is the internal shock model. We propose an alternative model in which the radiating fluid in the GRB shell is relativistically turbulent with a typical eddy Lorentz factor γt. In this model, all pulses in the gamma-ray light curve are produced at roughly the same distance R from the centre of the explosion. The burst duration is ~R/cΓ2, where Γ is the bulk Lorentz factor of the expanding shell, and the duration of individual pulses in the light curve is ~R/cΓ2γ2t. The model naturally produces highly variable light curves with ~γ2t individual pulses. Even though the model assumes highly inhomogeneous conditions, nevertheless the efficiency for converting jet energy to radiation is high.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- March 2009
- DOI:
- 10.1111/j.1745-3933.2009.00624.x
- arXiv:
- arXiv:0812.0018
- Bibcode:
- 2009MNRAS.394L.117N
- Keywords:
-
- radiation mechanisms: non-thermal;
- gamma-rays: bursts;
- Astrophysics
- E-Print:
- Submitted to MNRAS