On the populating mechanisms of the autoionising states of Al III ions produced in a Penning ionisation discharge

Abstract
The enhanced radiation of the 2p63p-2p53s3p autoionising lines emitted by Na I-like, Al III ions in a Penning ionisation discharge is explained by an inner-shell ionisation process of the Al+ ion in its excited state. This explanation is based on the analysis of the Al II and Al III spectra emitted in the 100-1900 AA range, and comparison with theoretical computations.