A hélium autoionizációs állapotai közötti interferencia (e,2e) kísérleti vizsgálata

Abstract

The electron impact excitation of the autoionizing states of helium, their decay into the common He⁺¹s^-1 final ionic state with energy 24.6 eV, and the interference of these processes are studied. The scattered-ejected electron pairs are observed in coincidence by two electron spectrometers, a constant ionic state (e,2e) experiment (CIS) is performed, isolating the final state by keeping the sum of transmission energies of the spectrometers constant. In the focus of this work are the exchange interference effects of 2s²(¹S) and 2p²(¹D) autoionizing states of helium. Around the critical energy (where the energy of the scattered electron from one reaction path equals the energy of ejected electron from the other reaction path), a few tenths of eV modification in primary energy causes a significant change in the CIS spectra, which indicates the presence of exchange interference effects.