Experimental Studies of High-Mach-Number Magnetized Collisionless Shocks in Laboratory Plasmas

ORAL

Abstract

We review experiments undertaken on the Omega laser facility that study high-Mach-number magnetized collisionless shocks through the interaction of a laser-driven piston plasma and ambient plasma in an external magnetic field. Through time-resolved, 2-D refractive imaging and proton radiography we observe the formation of shocks with an Alfv\'{e}nic Mach number $M_A\sim15$ that occur over ion kinetic length scales. Additional measurements with optical Thomson scattering directly demonstrate the shock formation process through the evolution of the piston and ambient ion velocity distributions and their coupling through electric and magnetic fields. We also show particle-in-cell simulations constrained by experimental data that further detail how laser-driven piston plasmas generate magnetized shocks in laboratory plasmas. The results provide key features of the structure of piston-driven shocks and several criteria by which to determine when shocks have formed under laboratory conditions. The development of this experimental platform opens the way for controlled laboratory investigations of high-Mach-number collisionless shocks, including mechanisms of shock heating and particle acceleration.

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Authors

  • Derek Schaeffer

    Princeton University

  • William Fox

    PPPL, Princeton University, Princeton Plasma Physics Laboratory, PPPL

  • Amitava Bhattacharjee

    PPPL, Princeton University, PPPL, Princeton Plasma Physics Laboratory, Princeton University, Princeton University, Princeton Plasma Physics Laboratory

  • Jackson Matteucci

    Princeton University, Princeton Plasma Physics Laboratory

  • Gennady Fiksel

    U. Michigan, Ann Arbor, U. Michigan, University of Michigan, U.Michigan, Ann Arbor

  • Chikang Li

    Massachusetts Institute of Technology, MIT, university of chicago

  • Kai Germaschewski

    U. New Hampshire, Durham, University of New Hampshire

  • Daniel Barnak

    Laboratory for Laser Energetics

  • Russ Follett

    Laboratory for Laser Energetics, Laboratory for Laser Energetics, University of Rochester, University of Rochester, LLE rochester

  • Dan Haberberger

    Laboratory for Laser Energetics

  • S. X. Hu

    Laboratory for Laser Energetics, Laboratory for Laser Energetics, University of Rochester, University of Rochester