Resonance lines of hydrogenlike aluminum ions emitted from a high-power laser-produced plasma have been recorded using a novel ultrahigh-resolution double-crystal x-ray spectrometer. The resolution provided by this instrument allows, for the first time, well resolved emitted line profiles and positions to be measured as a function of observation angle. Interpretation of the measured line shapes, positions, and intensities require simulations which include the transfer of radiation in a plasma with a large velocity gradient.

• Received 24 September 1993

DOI:https://doi.org/10.1103/PhysRevLett.72.1826