Super-Alfv\'{e}nic Expansion of a Laser-Plasma through an Ambient Magnetized Plasma

ORAL

Abstract

In recent experiments on the Large Plasma Device (LAPD) several diagnostics have been implemented to investigate the super-Alfv\'{e}nic flows created by the rapid expansion of a high-density, energetic laser-plasma through the ambient magnetized, helium plasma of the LAPD. The laser-plasma is created by a $25$ J, $5$ ns FWHM laser pulse of $1064$ nm light incident on a graphite target and is allowed to expand a distance $>30$ cm across the magnetic field lines. With the laser-plasma expansion imparting enough energy to the low-density ambient plasma ($n\sim2\times10^{-12}$ cm$^{-3}$, $T_{e}\sim6$ eV, $T_{i}\sim1$ eV, $B_{o}=300$ G), super-Alfv\'{e}nic flows can be created. The magnetic structure of these flows has been measured using a $1$ mm, 3-axis differential magnetic probe (B-dot probe). A measurement of the energy distribution of ions has also been attempted using an energy analyzer.

–

Authors

  • Erik Everson

    • University of California, Los Angeles

  • Carmen Constantin

    • University of California, Los Angeles

  • Lucas Morton

    • University of California, Los Angeles

  • Derek Schaeffer

    • University of California, Los Angeles

  • Nathan Kugland

    • University of California, Los Angeles

  • Walter Gekelman

    • University of California, Los Angeles

  • Christoph Niemann

    • University of California, Los Angeles