Time of Neutron Production on Z-Pinch and Plasma Focus Devices.

In this paper we present the results obtained on the plasma focus PF-1000 in IPPLM Warsaw and on the z-pinch S-300 in RRC Kurchatov Institute in Moscow using a deuterium load. On the PF-1000 plasma-focus device with deuterium filling gas the energy of neutrons and time of their generation are determined by time-of-flight method from seven scintillation detectors positioned in the axial direction. The neutron signals (total yield ∼1011 neutrons per shot) correlate with hard x-rays and their maximum occur ∼150–200 ns after the pinch phase. The initial portion of neutron pulse has beam-target origin with downstream energies up to 2.8–3.2 MeV and the final portion of neutrons has isotropic distribution of energies in the range of 2.2–2.7 MeV. The z-pinch experiments were performed on the S-300 generator with the load formed from a deuterated CD2 fibre in the axis of a tungsten wire array. The energy of neutrons and time of their generation are determined by time-of-flight method from 5 scintillation detectors positioned in the axial and side-on direction. The neutrons with total yield up to 3×109 per shot are produced in the energy range of 1.8–3.2 MeV at 10–30 ns after the pinch phase represented by dip in the current waveform, peak of the voltage and minimum of the pinch diameter. The distribution of neutron velocities is random within the total solid angle. The neutrons in both devices are produced by a non-thermal mechanism with deuterons accelerated to the energies above 100 keV partially in anode-cathode direction and partially with almost isotropic distribution of velocities at the time of the plasma expansion, i.e. after the pinch phase. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]