The photoionization of neutral aluminium

Abstract

The R-matrix method is used to calculate the photoionization cross section of ground state aluminium atoms Al(2P0), leaving the residual ions in their ground Al+(1Se) or first two excited states Al+(3P0,1P0). The initial bound state Al(2P0) as well as the three possible final continuum states (Al++e-)(2Se,2Pe, 2De) are represented consistently by R-matrix expansions in terms of three lowest states of the ion Al+(1Se,3P0,1P0). These ionic states are in turn described by accurate configuration-interaction wavefunctions. Good agreement is obtained with recent experiments by Kohl and Parkinson (1975) and by Esteva (1974) and results probably accurate to better than 15% are given from 2070 AA to 570 AA.