Radiative transfer and transverse inhomogeneity effects in spectral lines emitted from laser plasmas

Abstract

With the purpose of refining diagnostic methods for laser plasmas and of improving technological applications such as X radiation sources and X-ray lasers, the authors have examined the combined effects of radiative transfer and temperature transverse gradient on spectral line intensities. To this end they have used composite targets with a suitable geometry and a varying transverse dimension. The measurements concern mainly Al H gamma , Al Hegamma and Al Hbeta , Al Hebeta spectral lines. The latter are sensitive to both the inhomogeneity and radiative transfer effects while the former depend essentially on the temperature gradient. The comparison between theoretical results and experimental ones has shown that plasmas with a large transverse dimension (D>or approximately=40 mu m) are simultaneously inhomogenous and self-absorbent.