High-resolution spectroscopy of laser-produced L-shell molybdenum plasma

A wide variety of spectroscopic methods are used for the diagnostics of laser-produced plasma. One particularly powerful diagnostic is high-resolution emission-line spectroscopy, in conjunction with atomic calculations and radiation hydrodynamic simulations. In this work, we present line-resolved spectra of L-shell molybdenum (Z=42) produced by high-energy laser pulses of ~200-400 J at a wavelength of 351nm, with durations of 1-3 ns. The experiments were conducted at the National Laser Facility, Soreq, Israel. Time integrated spectra were recorded in the range of 2-4.1 keV with a high-resolution crystal spectrometer (E/ΔE>400). Lines of F-like Mo+33 – Al-like Mo+29 were identified, although the spectrum is dominated by the intense Ne-like Mo+32 lines. Collisional-radiative calculations using the HULLAC and NOMAD codes are in good agreement with the experimental results, providing estimates of an electron temperature of 0.9-1.5 keV, and an electron density of 0.6-3.0 x 10^21 cm-3 originating from the coronal region of the plasma.