It was found that a new type of solid-state detector known as the self-scanning photodiode array can be used to obtain the active readout of data in wavelength-dispersive x-ray spectrometers. The use of this device to recover x-ray spectral data for glass microspheres heated by Lawrence Livermore Laboratory's CYCLOPS laser is reported. The self-scanning photodiode array is a product of the MOS electronics fabrication technology. It consists of an array of semi-discrete diffused junction photodiodes deployed along a line on a silicon chip. The signals generated in the array of diodes are serially-scanned and multiplexed by a scanning circuit built on the chip. The sensitivity and other aspects of the response of the photodiode arrays to low-energy x-rays has been previously reported. The photodiode array was used in conjunction with a flat KAP single-crystal in a series of spectrometry experiments. Of particular interest has been the analysis of the hydrogen-like and helium-like 1s-2p radiations of silicon in the neighborhood of 2 keV.

Absolute spectral measurements were made of electrons escaping from plasmas produced by focusing 5-10 J, 50-100 picosecond, 1.06 ..mu..m laser pulses on 10 ..mu..m thick Parylene disk targets. Nine spectral bands with 3 to 7.5 keV resolution were obtained from 30 to 190 keV using a 90/sup 0/ focusing permanent magnet spectrometer and appropriately positioned silicon electron detectors.

This paper is a discussion of curved crystal x-ray spectrometry of laser induced plasmas for h..nu.. < 4 keV. The plasmas were produced by a short pulse (<200 ps) of 1.06 ..mu.. (neodymium glass) radiation on glass shells on the order of a hundred ..mu..m in diameter and a micron thick. Total absorbed laser energy is of the order of 10 joules and x-radiation .01-.1 joule/sr. The shells were filled with DT gas under compression.