The absorption spectrum of Sr I between 40 and 95 Å

Structures due to excitation from the 3d and 3p subshells have been observed in the absorption spectrum of Sr I, as well as some window resonances attributed to excitation of two electrons, one from the 3d and one from the 4p subshell. The latter resonances are believed to be the first example to date of simultaneous excitation from two inner shells. The structure is complicated by the collapse of the 4d wave function in the presence of an excited core. A pronounced delayed onset of continuous absorption beyond the 3d limits is compared with theoretical predictions for Z = 36.