Energy Required to Produce One Ion Pair in Several Noble Gases

The absolute values of W, the energy to produce one ion pair, for electrons have been determined for purified noble gases. A parallel plate extrapolation ionization chamber, which could be evacuated, was used. The gases investigated were H₂, He, Ne, A, Kr, and Xe; and the absolute values of W were 36.3; 40.3; 35.3; 25.8; 24.7; 22.0 ev respectively based on W for air being 33.9 ev.