Planar radio-frequency ion source drive-in target neutron tube

Abstract

The invention belongs to a neutron source, and particularly relates to a turn-off planar radio-frequency ion source drive-in target neutron tube. The neutron tube is mainly composed of a planar radio-frequency ion source, a gas storage element, accelerating electrodes, a target and a vacuum system. The planar radio-frequency ion source substitutes for a penning source and is composed of a small-recombination-coefficient quartz discharge cup, a planar helical antenna clinging to the cup bottom and a Kovar material leading-out pole sealing the cup rim, a cusped magnetic field is formed by a plurality of magnets along the tube diameter of the discharge cup, plasma density is increased, and electron motion is limited while recombination losses of the tube wall are reduced. Radio-frequency power is transmitted to plasma from the antenna by means of inductive coupling. A shielding case is added to the outside of the ion source, influence of the radio-frequency electric field on other equipment is reduced, saturation adsorption of deuterium-tritium gas is realized by the internal gas storage device, and heating release is performed. The proportion of monatomic ions is increased greatly, utilization rate of reaction gas is increased, sputtering of a leading-out hole is reduced, and accordingly yield of the neutron tube is increased while service life of the same is prolonged.

Description

technical field [0001] The invention belongs to a neutron source, and in particular relates to a target-forming neutron tube of a planar radio-frequency ion source that can be shut off. Background technique [0002] Neutron sources are widely used in petroleum logging, coal quality analysis, homeland security, and non-destructive imaging detection. Natural radioactive sources are always in a radioactive state and have no pulse type, which limits the analytical application and is likely to cause personal danger in manufacture, storage and use. Compact neutron generators based on accelerator technology and polymerization reactions avoid the problems associated with natural radioactive sources and offer advantages in size and energy consumption compared to reactors and large accelerator systems. [0003] The neutron tube is the core component of the neutron generator. At present, domestic commercial neutron tubes mostly use Penning ion sources, which have the advantages of si...

AI Technical Summary

Problems solved by technology

However, the extracted deuterium-tritium ion beam contains a variety of ions, of which molecular ions account for more than 90%, while monatomic ions account for less than 10%. When polyatomic ions hit the target nucleus, the energy participating in the nuclear reaction accounts for about 1 / n of the total energy. (n is the number of atoms in the ion), also contributes little to the neutron yield, reducing the efficiency of the accelerator

In addition, polyatomic ions cause sputtering loss to the cathode hole material and target film, which affects the life and stability of the neutron tube

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