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

Journal Article · Thu Aug 15 04:00:00 EDT 2013 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.4818146· OSTI ID:22220666

Welch, D. R.; Rose, D. V.; Thoma, C.; Clark, R. E.; Miller, C.; Madrid, E. A.; Zimmerman, W. R. ^[1]; Rambo, P. K.; Schwarz, J.; Savage, M.; Atherton, B. W. ^[2]

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1. Voss Scientific, LLC, Albuquerque, New Mexico 87108 (United States)
2. Sandia National Laboratories, Albuquerque, New Mexico 87185-1196 (United States)

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.

• OSTI ID: 22220666
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 8 Vol. 20; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

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