Simulation of K-$\alpha$ Emission from Highly Charged Cu ions for Pinches on ZR

Recent spectral data of Cu shots Z1975 and Z2122 from Sandia's ZR machine are believed to show strong K-$\alpha $ emissions. As these K-$\alpha $ lines provide good diagnostics, a detailed spectral model will be developed to investigate these line emissions for analyzing the data. In a Z pinch plasma, K-$\alpha $ emission can occur due to e-beams, hot electrons at the tail of a Maxwellian and also pumping from hot photons emitted near the axis. K-$\alpha $ emission that originates from collisional processes involving hot electrons in the final phase of the pinching plasmas are associated with radiationless electron capture, inner-shell electron collisional excitation and ionization. K-$\alpha $ lines from various ionization stages of various materials such as Fe, Cr, Ni, and Mn were also observed in the ZR data. Contributions from ions with strong K-$\alpha $ transitions will be included for this study which is a preliminary attempt to investigate Cu K-$\alpha $ lines due to hot electrons and photons. Photo-pumped K-$\alpha $ emission from an outer shell is spatially distinguishable from that produced by e-beam on axis.