Investigation of UV laser ionization in naphthalene and phenol vapours added to proportional chamber gases

Abstract The ionization induced in organic vapours added to argon-methane proportional chamber gas by an UV laser emitting at a wavelength of 266 nm has been studied. At concentrations of 30–70 ppm and laser energy densities of 1 μJ/mm 2 , ionization densities of 10 3 electrons per mm 3 are obtained. These vapours are adsorbed by the chamber walls and difficult to remove. Procedures for gas cleaning are given.