Production of energetic protons, deuterons, and neutrons up to 60 MeV via disruption of a current-carrying plasma column at 3 MA

• Published in: New journal of physics 2020-10, Vol.22 (10), p.103036
• Main Authors: Klir, D, Shishlov, A V, Kokshenev, V A, Jackson, S L, Rezac, K, Cherdizov, R K, Cikhardt, J, Dudkin, G N, Fursov, F I, Krasa, J, Kravarik, J, Kubes, P, Kurmaev, N E, Munzar, V, Ratakhin, N A, Turek, K, Varlachev, V A
• Format: Article
• Language: English
• Subjects: Acceleration; accelerator; Current carrying plasmas; current disruption; Deuterons; Disruption; Electric potential; Electron beams; Electronic devices; Energy; Fast neutrons; Hydrogen ions; Ion beams; Neutron beams; Neutrons; Nuclear reactions; Particle accelerators; Particle beams; Physics; Plasma; plasma device; plasma instabilities; plasma opening switch; power multiplication; Protons; Space plasmas; Voltage; z-pinch; Zeta pinch
• ISSN: 1367-2630; 1367-2630
• DOI: 10.1088/1367-2630/abbab5

Acceleration of ions to multi-MeV energies is investigated in various plasma devices to better understand processes in astrophysical plasmas and to develop efficient accelerators for a variety of applications. This paper reports the production of proton, deuteron, and electron beams in a z-pinch-a cylindrically symmetric plasma column that is compressed by its own magnetic field. For this work, the GIT-12 pulsed-power generator was used to drive a novel configuration of z-pinch that dramatically enhanced ion acceleration associated with disruption of the current by instabilities in the compressed plasma. During the disruption of 3 MA current, hydrogen ions were accelerated up to at least 50 MeV, which is almost a hundred-times the ion energy provided by the generator driving voltage of 0.6 MV. Under optimal conditions, the total numbers of hydrogen ions with energies above 20 and 50 MeV were 4 × 1013 and 1011, respectively. Accelerated deuterons produced one 20 ns (full width at half maximum) pulse of fast neutrons via D(d, n)3He and other nuclear reactions. A maximum neutron output of (1.0 ± 0.2) × 1012 neutrons/sr was observed downstream, i.e., in the anode to cathode direction. In this direction, the maximum neutron energy reached 58 ± 7 MeV. Both ion and neutron beams in our experiment reached an end-point energy of about 60 MeV, which is the highest value observed in pulsed-power devices. A localized peak voltage of ≳60 MV was driven by the inductive energy that was stored around the plasma column and that was extracted during a sub-nanosecond current drop. Considering the natural occurrence of current-carrying columns in laboratory and space plasmas, the current interruption observed in z-pinches could represent a more general physical process that contributes to the efficient conversion of magnetic energy into the energy of particle beams in various plasmas.