Linear discriminant analysis of electron beam effects on the relativistic laser-produced K-shell Al plasmas

Summary form only given. Linear Discriminant Analysis (LDA) is applied and compared with the Principal Component Analysis (PCA) and the H- and He-like line ratio diagnostics to investigate the electron beam effects on the laser produced K-shell Al synthetic spectra^1,2. The experiments were performed at the Leopard Laser Facility of NTF/UNR (1.057 μm Ti:Sapphire/Nd:glass laser system) with 0.8 ns pulses with 15 J of energy, focused into 10 μm diameter spot on the 50 μm thick flat Al foil target. The spectrum was obtained by the high resolution focusing spectrometer with spatial resolution using a spherically bent mica crystal. The plasma electron temperature, density and electron beam fractions of laser produced K-shell Al plasma (Shot 556) were extracted using coefficients of discriminant and principal components produced from the non-LTE collisionally radiative K-shell Al model. The modeled plasma electron temperatures and densities are about Te~270 eV and ne=3×10²¹ cm^-3 in the presence of electron beams with fraction of f~0.05 and energy centered at ~10 keV.