Neutron emission generated during wire array Z-pinch implosion onto deuterated fiber

• Published in: Physics of plasmas 2008-03, Vol.15 (3)
• Main Authors: Klir, D., Kravarik, J., Kubes, P., Rezac, K., Anan’ev, S. S., Bakshaev, Yu. L., Blinov, P. I., Chernenko, A. S., Kazakov, E. D., Korolev, V. D., Meshcherov, B. R., Ustroev, G. I., Juha, L., Krasa, J., Velyhan, A.
• Format: Article
• Language: English
• Subjects: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; CYLINDRICAL CONFIGURATION; DEUTERONS; ENERGY SPECTRA; EXPLODING WIRES; FIBERS; HARD X RADIATION; IMPLOSIONS; KEV RANGE; KINETIC ENERGY; MEV RANGE; NEUTRON EMISSION; NEUTRON SPECTRA; NEUTRONS; PARTICLE BEAMS; PLASMA; PLASMA DIAGNOSTICS; POLYETHYLENES; X-RAY SOURCES
• ISSN: 1070-664X; 1089-7674
• DOI: 10.1063/1.2839352

The implosion of both cylindrical and conical wire arrays onto a deuterated polyethylene fiber was studied on the S-300 pulsed power generator [A. S. Chernenko et al. , Proceedings of the 11th International Conference on High Power Particle Beams (Academy of Science of Czech Republic, Prague, 1996), p. 154]. Neutron measurements were used to obtain information about acceleration of fast deuterons. An average neutron yield approached 10 9 on the current level of 2 MA . In the case of conical wire arrays, side-on neutron energy spectra peaked at 2.48 ± 0.05 MeV with 450 ± 100 keV full width at half-maximum. In the downstream direction, the peak neutron energy and the width of a neutron spectrum were 2.65 ± 0.10 MeV and 350 ± 100 keV , respectively. The total number of fast deuterons was 10 15 and their average kinetic energy was about 150 keV . Most of the deuterons were directed toward the cathode. The broad width of neutron spectra in the side-on direction implied a high radial component of deuteron velocity. With regard to the emission time, neutron pulses temporally correlated with hard x rays and also with measured voltage. The neutron emission lasted on average 30 ± 5 ns and it was observed during the stagnation and at the beginning of the expansion of a plasma column. At this moment, the plasma impedance reached 0.2 – 0.4 Ω . In the post-stagnation phase, this value was formed significantly by enhanced plasma resistance. Similar experimental results were observed also with cylindrical wire arrays imploding onto a deuterated fiber.