An investigation of the rapid rise time of incoherent x-ray emission from targets heated by an ultra-short pulse (USP) high-intensity optical laser was conducted for use as the x- ray source for inner-shell photo-ionized (ISPI) x-ray lasing. Previous studies considered front-side x-ray emission; however, ISPI x-ray lasing requires a filtered x-ray source. Modeling using the hydrodynamics/atomic kinetics code LASNEX of a 40 fs USP driving laser with an intensity of 10¹⁷ W/cm² incident on a flat target of thin Au layered on a Be filter is presented. The filter has a modest influence on the x-ray emission of the Au via conduction cooling but has a large effect on the backside spectrum by removing low energy x-rays as the Au emission passes through the filter. The use of such a filtered source is shown to provide the needed x rays to achieve high gain in C at 45 angstrom.

Date Published: 1 November 1997
PDF: 5 pages
Proc. SPIE 3156, Soft X-Ray Lasers and Applications II, (1 November 1997); doi: 10.1117/12.293385

Published in SPIE Proceedings Vol. 3156:
Soft X-Ray Lasers and Applications II
Jorge J. G. Rocca; Luiz Barroca Da Silva, Editor(s)