Experimental study of the effective secondary emission coefficient for rare gases and copper electrodes

Measurements are made for variations of the effective secondary emission coefficient γ with reduced field E/p. Plane-parallel copper electrodes (5 cm diameter) are sustained with a dc voltage (0<V<1 kV) and can be separated by a variable distance (2 mm<d<1 cm). Current–voltage characteristics, Paschen curves, and γ(E/p) variations are shown for various rare gases (neon, argon, krypton, and xenon). γ(E/p) values are deduced from Paschen curves and published α/p(E/p) variations by using the self-sustain condition. Comparisons are made with various experimental or calculated results taken from the literature.