Experimental and simulation study of spherically convergent beam fusion

Summary form only given. The experimental and simulation results of spherical glow discharge will be presented. The device is made of 50-cm diameter, 30-cm high stainless steel cylindrical chamber, in which a spherical anode of 30-cm diameter is set. The grid cathode is made of 1.9-mm diameter stainless steel wire, which is made into open spherical grids of 5-cm diameter, The system is maintained at a constant pressure of 1-15 mTorr by bleeding hydrogen or deuterium gas into the chamber through a leak valve. A 0-60 kV, 0-20 mA constant current DC power supply was used to power the device. Using deuterium, the neutron production was observed. The basic discharge characteristics such as the breakdown voltage versus pressure, the operating voltage versus current with changing the gas pressure were measured. The motions of ions and electrons in the device were simulated using a particle code, which is one-dimensional in coordinate system and two-dimensional in velocity space. The simulation shows that a shallow potential well for ions is formed in the central part inside the grid cathode. However, the well is observed to be very unstable.