Threshold Law for Double Photoionization and Related Processes withL=1Final States

The energy dependence at threshold for the escape of two electrons with total angular momentum $L=1\mathrm{}$ is shown to be the same as that found for $L=0\mathrm{}$ by Rau, and classically by Wannier, for processes that leave the same residual ion. It is suggested that this threshold law will also hold for $L>\mathrm{}1\mathrm{}$.