Z-pinch plasma neutron sources

Abstract

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Experimental Demonstration of Fusion-Relevant Conditions in Magnetized Liner Inertial Fusion

“…This is consistent with expectations since the implosion velocity (70 km/s) is too low to generate such high temperatures in a non-magnetized, non-preheated target. The isotropic, near-Gaussian DD NTOF spectra, DD yield isotropy, high ion and electron temperatures (with T i ≈ T e ), and the large secondary DT yield provide evidence for a thermonuclear origin of the yield rather than beam-target reactions, which have been suggested as a significant source of yield in other magnetically-driven implosions [32][33][34]. The range of measured DD yields (5e11-2e12) is encompassed by the 2e11-6e13 thermonuclear yield range estimated based on the 0.2-0.6 g/cm 3 fuel density (from x-ray yield), 2-3.1 keV temperature (from NTOF and x-ray spectra), 0.02-0.05 mm 3 volume (from x-ray imaging), and 1-2 ns duration (from x-ray emission history).…”

Study of D-D Reaction at the Plasma Focus Device

“…The relaxation time of Coulomb interaction for deuteron-deuteron collisions given by formula τ ii = 2.3x10 13 (T(eV) 3/2 /n.lnΛ) and the relaxation time of Coulomb interaction for deuteron-deuteron collisions has the value of 10-40 ns (for n i = 10 25 and E d =(1-2) keV), while the time of equilibrium between electrons and ions in these conditions given by Coulomb interaction τ ei = τ ii (m/M) 1/2 (Ei/Te) 3/2 is effective for electron temperature below 0.1 keV [13]. Fast ions can produce an additional heating of deuterons and electrons [14,15] of the target.…”

Transition from Beam-Target to Thermonuclear Fusion in High-Current DeuteriumZ-Pinch Simulations

“…Neutron yields in dense Z-pinch experiments and in numerical simulations are generally observed as scaling with the current to the fourth power [1][2][3]. A deviation from a single I 4 scaling exists for currents around a few mega-amps [4].…”