Comment on “On the mechanism of liquid metal electron and ion sources”

Abstract

The electric field near the anode of an electrohydrodynamic ion source is analytically discussed. For the field at the anode apex a rigorous analytical treatment results in the simple expressionE ₀ ≅V _AC/(P₀R₀)^1/2 differing by a factor of 1/2/32 from that by Gomer. Here,V _AC is the applied potential to the cathode with regard to the anode,R ₀ the cathode distance from the anode center, andP ₀ the radius of curvature at the apex of the anode surface. The analytical forms for the radius of curvature and the electric field direction as well as the electric field itself at arbitrary points on the anode are derived.