Line shapesin photoexcitation of triply excited hollow states

Abstract

Taking as the point of departure a frequently used experimentaldetection scheme, we present a derivation of the analyticalexpressions of the line shapes in partial decay channelspertaining to photoexcitation of triply excited hollow statesin atomic lithium with subsequent autoionization into a specificdoubly excited state in the singly charged ion. The line shapesrepresent useful generalizations of the Fano parametrizationof the profile of an autoionizing resonance. The line shapesgive the positions and widths of the triply excited autoionizingresonances, and carry information about specific partialautoionization widths, and partial asymmetry parameters. It isalso shown that a laser-induced transition from thetriply excited state to another lower-lying one can be usedto gain direct information about partial widths. The schemesare readily implemented experimentally, and would allow forthe first measurements of such quantities.