X-ray-absorption features from multielectron excitations above XeLedges

The x-ray-absorption cross section above the $L$ edges in xenon gas has been measured using synchrotron radiation. Multielectron excitation effects are investigated over a few hundred eV region from the Xe $L_{\mathrm{I}},$ $L_{\mathrm{II}},$ and $L_{\mathrm{III}}$ edges and the contributions from the effects of shake-up and shake-off to the photoabsorption spectrum are elucidated. Several multielectron excitation features were detected and analyzed by the theoretical energy of the shake-up process. Previous observations of the $\left[2\right(s,p\left)5\right(s,p\left)\mathrm{}\right]$ and $\left[2\right(s,p\left)4d\right]$ transitions have been confirmed. $\left[2\right(s,p\left)4p\right]$ transitions are clearly identified in the present study. It is very difficult to detect the $\left[2s3s\right]$ multielectron transition with the sensitivity of $\sim 2.0\times {10}^{-4}$ at the $L$ edge jump. The $\left[2s3d\right]$ edge was distinguished using the first derivative of the absorption curve. A new transition is found between $\left[2\right(s,p\left)4p\right]$ and $\left[2\right(s,p\left)4d\right]$ transitions and identified as a three-electron transition $\left[2\right(s,p\left)4d5p\right].$ Moreover, the difference in the behavior of the multielectron excitation as a function of x-ray energy among the $L_{\mathrm{I}}$ and $L_{\mathrm{II}},$ or $L_{\mathrm{III}}$ edges is confirmed and investigated.