Marko Cvejić - Video Lecture

Marko Cvejić - Video Lecture

IVS-IPSTA 2020 Online Conference December 13, 2020

Morning Plasma Session
Session chair:
Yoav Hadas

RAFAEL, Israel


Effects of plasma rotation in an experiment of magnetic flux compression by an imploding plasma

Marko Cvejić

Faculty of Physics, Weizmann Institute of Science, Israel


Abstract

Z-pinches with pre-embedded magnetic field undergo radial implosion while compressing the plasma and embedded magnetic flux. Our gas-puff experiments demonstrate that an axial magnetic field, Bz, makes the imploding plasma rotate. The direction of angular rotation velocity, ω, was found to be dependent on Bz, being antiparallel to Bz, direction. Also, ω was found to exhibit axial and radial variation, showing that the plasma does not rotate as a rigid body. The magnitude of the rotational velocity was found to be comparable to the peak implosion velocity; the self-generated rotation is shown to play a significant role in both the pressure and energy balance during the implosion phase and at stagnation. Also discussed is the possible impact of the rotation on the stabilization mechanisms of stagnating plasma. Temporally and spatially resolved spectroscopic measurements of all three components of the magnetic field, plasma parameters and ion motion enabled to elucidate the physical mechanisms leading to the plasma rotation in our experiments.