Coherent excitation of autoionizing resonances

[摘要] An electron-electron coincidence [or (e,2e)] technique was used to investigate atomic ionization by electron impact in the neighborhood of autoionizing resonances. Differing binary (I{sup +}) and recoil (I{sup -}) lobe intensities in coplanar (e,2e) ejected-electron angular distributions were analyzed in terms of interference cross-terms, between opposite parity final-state continua, that change sign when {theta}{sub ej} {yields} {theta}{sub ej} + 180{sup o} in the angular distributions. The magnitude of these cross-terms varies rapidly with ejected-electron energy across overlapping autoionizing resonances. The energy variation in the interference terms may be examined by obtaining the sum (I{sup +} + I{sup -}) and difference (I{sup +} - I{sup -}) of (e,2e) energy spectra measured at ejected-electron angles 180{sup o} apart.

[发布日期] 2002-10-03 [发布机构] University of Kentucky Research Foundation, Lexington, KY (United States)

[关键词] Parity;Interference Electron-Atom Collisions;Angular Distribution;Excitation;Resonances