skip to main content

Title: Kinetic simulation studies of laser-triggering in the Z gas switch

Advanced z-pinch accelerators require precise timing of multiple mega-ampere drivers to deliver terawatt power. The triggering of these drivers is now largely initiated by laser ionization of gas switches. In this paper, we discuss detailed fully kinetic simulation of the Z laser-triggered gas switch involving detailed finite-difference time-domain particle-in-cell Monte Carlo modeling of the trigger section of the switch. Other components of the accelerator from the Marx bank through the pulse-forming line are described as circuit elements. The simulations presented here build on a recently developed model of electro-negative gas breakdown and streamer propagation that included photons produced from de-excited neutrals. New effects include multi-photon ionization of the gas in a prescribed laser field. The simulations show the sensitivity of triggering to laser parameters including focal plane within the anode-cathode gap of the trigger section of the switch, intensity at focus, and laser pulse length. Detailed electromagnetic simulations of the trigger section with circuit modeling of the upstream and downstream components are largely in agreement with Z data and demonstrate a new capability.
Authors:
; ; ; ; ; ;  [1] ; ; ; ;  [2]
  1. Voss Scientific, LLC, Albuquerque, New Mexico 87108 (United States)
  2. Sandia National Laboratories, Albuquerque, New Mexico 87185-1196 (United States)
Publication Date:
OSTI Identifier:
22220666
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 20; Journal Issue: 8; Other Information: (c) 2013 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; BREAKDOWN; LASER RADIATION; LASERS; MONTE CARLO METHOD; MULTI-PHOTON PROCESSES; PHOTOIONIZATION; PHOTONS; PLASMA GUNS; PLASMA SIMULATION; PLASMA SWITCHES; SENSITIVITY