Neutron production characteristics and emission properties of spherically convergent beam fusion

Experimental results of spherical glow discharge for a portable neutron sou rce are presented. An experimental device consisting of a 45-cm-diam, 31-cm -high stainless steel cylindrical chamber was constructed in which a spheri cal mesh-type 30-cm-diam anode was installed. A spherical grid cathode made of 1.2-mm-diam stainless steel wire was made into a 7-cm-diam open spheric al grid. The system was maintained at a constant pressure of 1 to 15 mTorr by feeding hydrogen or deuterium gas. The visible and ultraviolet emissions from the device were measured using the spectroscopic method. Strong emiss ion lines of hydrogen were observed, and all hydrogen lines were broadened, remarkably, by Doppler and/or Stark effects. From these data, beam ion vel ocity, electron density and temperature of the core plasma were estimated U sing deuterium gas, a steady-state neutron production rate of 10(4) s(-1) w as observed at a discharge of 40 kV; 2 mA. In the low-current region of sev eral milliamperes, the neutron production rate was proportional to the disc harge current to the power from similar to1.1 to 1.4. The beam-background r eactions were dominant in the measured range of voltage and current.