New Mechanism for Resonant Photoemission

We present a mechanism for the resonance near the $3p$ threshold in the photoemission associated with the two-hole bound state in metals such as Cu and Zn. It is based upon the strong interaction between the $4s-4p$ conduction-band electrons and the two bound holes (the $3d^8$ configuration) resulting from the super Coster-Kronig decay of the $3p$ core hole. This effect also occurs in Ni but is not dominant.