Fusion-reaction-yield scaling with PF plasma current density

Summary form only given, as follows. The scaling of the neutron yield Y from D+D reactions and, specifically, of its fluctuations /spl Delta/Y from discharge to discharge was experimentally determined with four plasma focus machines, as a function of the peak plasma-current density J. The powering energy levels were W=6 kJ for one PF machine (PF/sub 1/), 20 kJ for two identical PF machines [but one (PF/sub 2/) with, the other (PF/sub 3/) without, field distortion element at the electrode breech to sharpen the plasma current distribution], 35 kJ and 50 kJ for a fourth machine (PF/sub 4/). The comparative tests at 20 kJ and 35 kJ had the same peak electrode current I=1 MA the same charging voltage of the capacitor bank 25 kV, the same ratio inductance/capacitance (L/C), but with C(PF/sub 4/)=2C(PF/sub 2/) and L(PF/sub 4/)/spl equiv/[T(PF/sub 4/)/2/spl pi/]/sup 2//C(PF/sub 4/)=2L(PF/sub 2/). T(PF/sub 4/)/spl sime/1.4 T(PF/sub 4/), is the measured period of the complete PF electric circuit, including the propagating current sheet between coaxial electrodes. The bearing on Y, /spl Delta/Y of the breech overvoltage during the pinch collapse and of the variations of J is experimentally determined. The data indicate that MaxY(PF/sub 4/)/spl sime/mean value Y/sub Av/(PF/sub 2/) of Y, Y/sub Av/(PF/sub 2/)/spl sime/3Y/sub Av/(PF/sub 3/). The neural network analysis connecting Y and the current sheet multiplicity in the same discharge, was carried out as in earlier experiments.