Spot spectroscopy: Local spectroscopic measurements within laser-produced plasmas

Abstract
Use of a locally embedded tracer in laser‐irradiated solid targets yields a localized source of diagnostic x‐ray line radiation in the blowoff plasma. This technique potentially eliminates problems of chord integration over regions of varying density and temperature in an inhomogeneous plasma, and reduces complications due to plasma opacity effects in the interpretation of spectra. Spectra obtained in an experimental test of this new technique are of a quality superior to those obtained from standard laser‐produced plasmas, and should provide the best tests to date of spectroscopic models for these plasma conditions.