MHD Simulations of the Collapsar Model for GRBs
نویسندگان
چکیده
We present results from axisymmetric, time-dependent magnetohydrodynamic (MHD) simulations of the collapsar model for gamma-ray bursts. Our main conclusion is that, within the collapsar model, MHD effects alone are able to launch, accelerate and sustain a strong polar outflow. We also find that the outflow is Poynting flux-dominated, and note that this provides favorable initial conditions for the subsequent production of a baryon-poor fireball.
منابع مشابه
Magnetohydrodynamic simulations of the collapsar model for early and late evolution of gamma-ray bursts.
I present results from magnetohydrodynamic (MHD) simulations of a gaseous envelope collapsing onto a black hole (BH). These results support the notion that the collapsar model is one of the most promising scenarios to explain the huge release of energy in a matter of seconds associated with gamma-ray bursts (GRBs). Additionally, the MHD simulations show that at late times, when the mass supply ...
متن کاملThe Mhd Collapsar Model for Grbs: an Inflow Produces an Outflow
We present our recent results from numerical simulations of a magnetized flow in the vicinity of a black hole in the context of the collapsar model for GRBs. The simulations show that after an initial transient, the flow settles into a complex convolution of several distinct, time-dependent flow components including an accretion torus, its corona and outflow, an inflow and an outflow in the pol...
متن کاملMagnetohydrodynamic simulations of the collapsar model for early and late evolution of gamma-ray bursts
I present results from magnetohydrodynamic (MHD) simulations of a gaseous envelope collapsing onto a black hole. These results support the notion that the collapsar model is one of most promising scenarios to explain the huge release of energy in a matter of seconds associated with Gamma Ray Bursts (GRB). Additionally, the MHD simulations show that at late times, when the mass supply rate is ex...
متن کاملThe Proto-neutron Star Phase of the Collapsar Model and the Route to Long-soft Gamma-ray Bursts and Hypernovae
Recent stellar evolutionary calculations of low-metallicity massive fast-rotating main-sequence stars yield iron cores at collapse endowed with high angular momentum. It is thought that high angular momentum and black hole formation are critical ingredients of the collapsar model of long-soft γ-ray bursts (GRBs). Here, we present 2D multi-group, flux-limited-diffusion MHD simulations of the col...
متن کاملAxisymmetric MHD simulations of the collapsar model for gamma-ray bursts
We present results from axisymmetric, time-dependent magnetohydrodynamic (MHD) simulations of the collapsar model for gamma-ray bursts. We begin the simulations after the 1.7 M⊙ iron core of a 25 M⊙ presupernova star has collapsed and study the ensuing accretion of the 7 M⊙ helium envelope onto the central black hole formed by the collapsed iron core. We consider a spherically symmetric progeni...
متن کامل