Studies of strong-field effects in multiphoton subpicosecond excited plasmas: Soft X-ray fluorescence and propagation

Abstract

Studies concerning two aspects of the strong-field multiphoton response of matter are discussed, namely, (1) the generation of excited states and (2) the propagation of extremely intense radiation in plasmas. Fluorescence in the 7 -79 nm region arising from excited ionic states produced in gas targets composed of the rare gases and N 2 is examined. Emissions from complex transition arrays stemming from open nd configurations in Kr and Xe are observed. Strong-field conditions are expected to produce significantly altered characteristics of propagation in plasmas which include the possibility of a new mode of channeled propagation.I.