[SEMINARI] Dr. M.V. Barkov Gamma ray bursts central machine as magnetically driven collapsar model

[Enric Marco]

Gamma ray bursts central machine as magnetically driven collapsar model

Dr. M.V. Barkov
Department of Applied Mathematics (University of Leeds, UK)
Space Research Institute (Moscow, Russia)


Lloc: Seminari del Departament d'Astronomia i Astrofisica
Dia: Dijous, 26 de juny 2008 (26/6/2008)
Hora: 12:00 h


Abstract: In this work we describe the results of our numerical study
on the possibility of magnetic origin of relativistic jets of long duration
gamma ray bursts within the collapsar scenario.
We track the collapse of massive rotating stars onto a rotating central black
hole using axisymmetric general relativistic magnetohydrodynamic code that
utilizes a realistic equation of state of stellar matter,
takes into account the cooling associated with emission of neutrinos,
and the energy losses due to dissociation of nuclei. The neutrino heating
is not included.  We describe the solutions for several models  where the
progenitor star has different magnetic field and for different envelop
accretion rates.
The some solution exhibits strong explosion driven by the
Poynting-dominated jets whose power exceeds up to
$12\times10^{51}\,\mbox{erg s}^{-1}$. The criterion for explosion were
derived. The jets originate mainly from the black hole and they are powered via
the Blandford-Znajek mechanism. A number of simulation movies can be downloaded
from http://www.maths.leeds.ac.uk/~serguei/research/movies/anim.html

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