THE CONTRIBUTION OF AUTOIONIZING STATES TO THE CROSS-SECTION OF 2-PHOTON IONIZATION OF MAGNESIUM ATOMS

The total cross section of two-photon one-electron ionization of magne sium atoms is calculated with regard to the contribution of autoionizi ng states of low-lying S-1 and D-1 series. It is demonstrated that aut oionizing states give rise to an additional resonance structure in the total and differential cross sections. The amplitude of multiphoton p rocesses was determined in the quasienergy approach. The spectroscopic parameters of discrete and autoionizing states were calculated by the method of configuration superposition. The contribution of autoionizi ng states is analyzed within the framework of the diagonalization appr oximation.