Current disruption and electric field in dense plasma focus

ORAL

Abstract

Plasma Physics Division at NRL is running a Dense Plasma Focus (DPF) experiment on the HAWK pulsed power generator (640 kV, 665 kA peak current). This experiment and many similar devices in the past produced neutron yields orders of magnitude above the thermal neutron yield suggesting that some mechanisms accelerate ions to energies well above thermal energy. We modeled the experiment using MHD code Athena coupled to an equivalent circuit model for HAWK and confirmed that the thermal yield is indeed much smaller than the observed yields. In addition we modeled particles accelerated in the motional vxB fields with the code Hephaestus and confirmed that this acceleration can only give particles with energies up to 0.2 MeV. To study potential non-MHD mechanisms of acceleration we introduced physically motivated, but artificial current disruption and calculated resulting electric and magnetic fields. We will report on the morphology and the energy spectrum of the neutron source described by such model.

Presenters

  • Andrey Beresnyak

    Consultant to NRL through RSI, Consultant to NRL through RSI, Lantham, MD, USA

Authors

  • Andrey Beresnyak

    Consultant to NRL through RSI, Consultant to NRL through RSI, Lantham, MD, USA

  • J. L. Giuliani

    Naval Research Lab, Naval Research Laboratory, Plasma Physics Division, Naval Research Laboratory, U.S. Naval Research Lab, Plasma Physics Division, NRL

  • Stuart L. Jackson

    Naval Research Laboratory, Plasma Physics Division, Naval Research Laboratory, Naval Research Lab

  • A. Stephen Richardson

    Naval Research Laboratory, Plasma Physics Division, Naval Research Laboratory, US Naval Research Laboratory, Plasma Physics Division, Naval Research Lab

  • A. L. Velikovich

    Plasma Physics Division, NRL, Naval Research Laboratory