The emission of H− ions from Penning-type ion source with metal hydride cathode in pulsating regime.

The operation in pulsating regime of gas-feed-free Penning-type H− ion source with metal hydride cathode and extraction in the longitudinal direction has been investigated. Hydrogen is stored in metal hydride in atomic state followed by the formation of rovibrationally excited H 2 * molecules due to the process of nonequilibrium desorption. It impacts on a Penning discharge ability to emit negative hydrogen ions in the longitudinal direction and provides local gas injection to the discharge without any external gas supply. The AC power input of 65 W during τ ≈ 15 μs was performed against the background DC one of 5 W. The extracted axial flux of charged particles was separated in an electromagnetic filter followed by the registration of H− current. The H− ion current of about 0.22 mA was obtained. In the DC regime it was only 5uA, which is order of magnitude below the current obtained with the present pulsating regime of source implementation. • Hydrogen uptake from metal hydride is the way of gas-feed-free ion sources creation. • Pulsating regime of discharge operation safely increases hydrogen desorbtion rate. • Metal hydride hydrogen activation results in efficient volume H− ions production. • Longitudinal extraction of H− ions from Penning-type ion source is possible in case of metal hydride cathode application. [ABSTRACT FROM AUTHOR]