Abstract

Measurement of the widths of lines emitted by x-ray lasers in the 50-250-Å range requires a spectral resolving power > 10,000. If it is desired to use a streak camera to measure the time variation of this width or the intensity of the line, the spectrum must be formed on a flat field that matches the configuration of the streak camera cathode. Conventional extreme ultraviolet/soft x-ray spectrographs—for example, those using a concave grating and that form the spectrum on an arc of the Rowland circle—do not have this combination of properties. We have designed and built a new form of spectrograph that uses a plane grating having a line spacing that varies across its width. In laboratory tests this instrument has achieved a resolving power of 35,000 in the 100–200 Å region. We have installed this instrument in the two-beam chamber at NOVA in LLNL and have measured the time-varying widths of lines from a number of x-ray lasers. Results from these experiments are presented.

© 1991 Optical Society of America