Astrophysics of magnetically collimated jets generated from laser-produced plasmas

TL;DR

This study uses 3D magneto-hydrodynamic simulations to demonstrate how magnetic fields in laser-produced plasmas can generate astrophysically relevant jets, revealing an alternative magnetic collimation mechanism.

Contribution

It introduces a novel mechanism showing magnetic fields can produce collimated jets from wide-angle winds in laser plasma experiments, paralleling astrophysical jet formation.

Findings

Magnetic fields > 0.1 MG can collimate plasma into jets.

Jets form via a standing conical shock at the cavity tip.

The mechanism parallels astrophysical inertial collimation models.

Abstract

The generation of astrophysically relevant jets, from magnetically collimated, laser-produced plasmas, is investigated through three-dimensional, magneto-hydrodynamic simulations. We show that for laser intensities I ~ 10^12 - 10^14 W/cm^2, a magnetic field in excess of ~ 0.1 MG, can collimate the plasma plume into a prolate cavity bounded by a shock envelope with a standing conical shock at its tip, which re-collimates the flow into a super magneto-sonic jet beam. This mechanism is equivalent to astrophysical models of hydrodynamic inertial collimation, where an isotropic wind is focused into a jet by a confining circumstellar torus-like envelope. The results suggest an alternative mechanism for a large-scale magnetic field to produce jets from wide-angle winds. (abridged version)