Investigation of the Electron Emitter Parameters of the Gas-Filled Neutron Tube's Penning Ion Source

Abstract

The paper presents results of physical processes modeling in the gas-filled neutron tube's Pennnig-type ion source with an electron emitter. The latter is a ring-shaped thermocathode of two different configurations: an internal radius of 2 mm and external radius of 3 mm and 5 mm. The features of the discharge dynamics depending on emitted electrons currents equal to 1 mA, 10 mA and 50 mA were investigated. At a current of 1 mA for a thin and wide ring, the value of the extracted ion current and front time do not exceed 200 ¼A and 3 ¼s respectively. In the case of currents of 10 mA and 50 mA for a thin emitter ring, the ion current maximum value does not exceed 700 ¼A and front time is less than 1 ¼s. For a wide ring, the maximum value of the extracted current reaches 900 ¼A, and the front time varies from 1 μs to 3 μs.