K-ALPHA EMISSION INDUCED BY X-RAYS FROM LASER-PRODUCED PLASMA

Experiments are conducted to study the effects of X-ray radiation and supra-thermal electrons produced by laser-produced plasma on the energy transport. Plasmas were produced by irradiating aluminum coated silicon targets (layered targets) with 1.06 µm Nd: glass laser of 1014 W/cm2 power density. The nanosecond time resolved X-ray spectra (1.5∼2.2 keV) were measured with the scintillator-photomultiplier array. The layer from which He-like ions are originated is limited to have a depth of 0.1µm into the target, and the Si Kα line emitting region has a depth of about 1 µm. The duration of Kα line signal is longer than that of A1 XII line (1s2p1P— 1s2 1S) signal. The Kα emission can be explained by X-ray absorption in the target material. © 1979, THE PHYSICAL SOCIETY OF JAPAN. All rights reserved.