Characterization of A Tubular Hot-Cavity Surface Ionization Source

A hot-cavity surface ionization source with a cylindrical cavity having a small inner diameter, d, and a length l>> d was studied. Measured ionization efficiencies for Sr, In and Al were higher than expected from surface ionization by a factor of 20, 50, and 200, respectively. The ionization mechanism based on a thermal plasma inside the hot cavity was used to explain the results.