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⁺(¹S^e) 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^-)(²S^e,²P^e, ²D^e) are represented consistently by R-matrix expansions in terms of three lowest states of the ion Al⁺(¹S^e,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.