Stark broadening of satellite lines in silicon plasmas driven by femtosecond laser pulses

Silicon targets irradiated at large incidence angle (60^∘{}) with ultrashort (120 fs) P-polarized laser pulses at high intensities ({}10¹⁶ W cm^-2) display significantly broadened K-shell x-ray line emission. To analyze the spectra we have calculated Stark-broadened line profiles for the He_α resonance line and its satellite transitions in Li-, Be-, and B-like ions with spectator electrons in theL and M shells. Results indicate that the emission is characteristic of near solid densities and that there is an unusually high contribution from high-order satellite transitions; this could be due to a combination of high-density and transient effects. {} 1996 The American Physical Society.