Hollow Cathode Discharges for Gas Lasers

Hollow Cathode Discharges for Gas Lasers

With the exception of the 632.8 nm neon line all the important visible and ultraviolet cw gas laser lines belong to the spectra of ionized atoms. To achieve proper laser oscillation the excitation of the upper levels of these lines is of primary importance. High energy electrons are needed for this process. As such electrons are in high concentration in the hollow cathode discharge, it was obvi...

Hollow Cathode Discharges - Analytical Applications

The low pressure glow discharges considered in this paper are the hollow cathode (Paschen), and the flat cathode (Grimm). Both discharges have similar voltage—current characteristics which are responsible for their radiation stability. The analytical sample is supplied to the discharge through a sputtering mechanism which provides a stable and non-selective source of particles. Some of the fund...

Transition characteristics of low-pressure discharges in a hollow cathode

Operation Modes of Hollow Cathode Arcs with Reduced Gas Flow

In 1971 the first research work on hollow cathode arcs (abbreviated HCA) started at Giessen University. Emphasis has been put on the operation of this hollow cathode arc for the ion beam neutralization of the electric propulsion unit RIT 10. In this application the HCA works as an electron source delivering electrons for main discharge starting and beam neutralization. But beside this, diagnost...

Comparison of hollow cathode and Penning discharges for metastable He production

The production of helium 2 1S singlet metastable atoms has been investigated using a hollow cathode discharge and a Penning discharge, under dc discharge conditions. The density of metastable atoms was measured by atomic absorption using the 2 1S–3 1P transition (501.57 nm). A range of plasma currents, varying from 16 to 180 mA, and a range of pressures, from 100 mTorr to 5 Torr, were investiga...