Abstract

Over the next decade, several astrophysical observatories will obtain high-resolution spectra of cosmic x-ray sources. Of particular interest are accretion-powered objects, such as active galactive nuclei, in which the x-ray emitting material is optically thick and therefore cannot be studied using the well-known models developed to explain the optically thin solar corona. In our laboratory, we are attempting to simulate optical depth conditions from which astrophysical processes can be modeled, including photoabsorption, recombination, and fluorescence. A laser-produced plasma, when time-resolved to separate collisional and radiative effects, can function both as a source of soft x rays and as the ionized plasma. The newly developed spectroscopic technique of varied line-space plane gratings is used to provide high spectral resolution at grazing incidence wavelengths, while maintaining stigmatic imaging and the normal incidence focal plane suitable for use with a streak camera detector. We report preliminary results using metal target plasma sources and x-ray film at the detection plane, verifying the predicted performance of the instrument. We have successfully recorded soft x-ray spectra employing two different collecting mirrors to feed convergent light to the grating: (1) a normal incidence multilayered mirror and (2) a grazing incidence Kirkpatrick-Baez mirror system.

© 1986 Optical Society of America