X-ray absorption spectroscopy of laser-produced plasmas: A study of the experiment and data analysis

Abstract

The novel technique of point-projection backlighting is used to probe a laser-produced plasma. A spatially restricted source of x rays is created by irradiating a fiber which is used to backlight a plasma. Temporal resolution of the absorption spectrum is obtained by creating the backlight with a pulse that is delayed in time from the main, plasma-producing, laser. The backlight can also be of shorter duration than the main laser pulse providing for enhanced time resolution and therefore less temporal averaging. The results for low-Z aluminum and silicon targets are presented. The low-Z absorption spectra using both low-Z (e.g., aluminum) and high-Z (e.g., molybdenum) elements for backlighting are studied. A description of this technique and the analysis of the data obtained is presented.