Relativistic Multichannel Treatment of Krypton Spectra across the First Ionization Threshold

The relativistic multichannel theory has been extended to calculate both the eigen quantum defects μ_α, transformation matrix U_iα, and the eigen dipole matrix elements D_α of krypton. The Rydberg and autoionization spectra of krypton across the first ionization threshold are calculated within the framework of multichannel quantum defect theory. Our calculated spectra are in agreement with the absolute measurement data.