Alpha-Particle Ionization Yields in a Gridded Chamber

The energy per ion pair for natural uranium alpha particles has been measured for several gases in a gridded parallel-plate ion chamber. Electron collection was used. The gases employed were He, Ne, A, Kr, N₂, A+3 percent CO₂, and A+5 percent N₂. On a relative basis, the results are in good agreement with those obtained by Jesse and Sadauskis using heavy ion collection. The absolute values herein reported are about 6 percent higher than those resulting from slow chamber measurements.