Krypton Heβ line spectrum including n = 2, 3 Li-like satellites with detailed Stark broadened line shapes

Abstract

We discuss the krypton He$\beta$ line spectrum including Li-like satellites with a spectator electron in n = 2 and n = 3 and detailed line shapes computed using standard Stark broadening theory for hot dense plasma conditions relevant to X-ray tracer spectroscopy of inertial confinement fusion implosion cores. The results show that the interference term in the electron broadening does not produce a significant effect for these satellite transitions. However, the effect of the electric field mixing of the energy levels driven by the ion’s microfield distribution does produce a significant change in the line shape. Level populations calculated with a collisional radiative atomic kinetics model were employed to obtain the photon energy resolved emissivity and opacity using the Stark line shapes, and the emergent intensity distribution was calculated by integrating the radiation transport equation along chords assuming a uniform spherical plasma source. The line spectrum has electron temperature ($T_e$) and density ($n_e$) sensitivity due to the temperature and density dependence of level populations and the density dependence of the Stark line shapes. Hence, this spectrum is suitable for a simultaneous temperature and density plasma diagnostic of implosion cores.