319 / 2019-02-15 00:58:34

Magnetized laser plasmas and their astrophysical applications

High energy density laboratory astrophysics

全体主题 > Fundamental Physics at Extremes

Mega-Gauss-level magnetic fields applied to laser produced plasmas are opening the door to a range of new studies in inertial confinement fusion, laboratory astrophysics, as well as to industrial applications.
Our experiments and related theoretical work have addressed the physics of magnetized accretion flows[1], jet collimation [2, 3] and variability[4], and more recent studies on ion-driven streaming instabilities and particle acceleration. The focus of this paper is on the modelling of these plasmas, the implications for astrophysical systems, and the role of the magnetized Rayleigh-Taylor instability in structuring these flows.
In particular we shall discuss the acceleration of charged particles to high-energies in colliding plasma flows. The plasma is generated by irradiating with a ns-laser, two oppositely facing solid targets. The expanding plumes are collimated into jets by an externally imposed magnetic field of 20 T and the collision of the two jets generates a region of strong shocks and turbulence. Measurements using a Thomson parabola indicate particles with energies up to ~ 1 MeV.
To understand the mechanisms leading to the acceleration of the particles, simulations are performed with the 3D resistive MHD code GORGON coupled with a test-particles solver. The dynamics of the plasma and the energization of the particles will be presented.

REFERENCES
[1] Revet et al, Science Advances, Vol. 3, no. 11, e1700982 (2017)
[2] Ciardi et al Physical Review Letters, 110, 025002 (2013)
[3] Albertazzi et al, Science, Volume 346, Issue 6207, pp. 325-328 (2014)
[4] Higginson et al, Phys. Rev. Lett. 119, 255002 (2017)