Satellite lines induced by electrons of near-threshold energy in the x-ray emission band spectra of 3d, 4d, and 5d transition metals

摘要

The Lβ_2 emission band (4d→2p_(3/2) transition) of selected transition metals of the 4d series (Y, Zr, Mo, and Ru) is studied under electron impact. Several spectra are recorded with electron energies as low as 15 eV above the 2p_(3/2) threshold. A satellite line is observed towards the high photon energy side of the normal emission. As the incident electron energy decreases and approaches the threshold energy of the emission, the intensity of the satellite line relative to that of the normal emission line increases. The satellite has also been observed above the emission bands of 3d (Fe) and 5d (W) elements. In contrast, in the case of Ag, the above satellite line has not been observed. Thus, its existence is common to all investigated nd elements having an open d shell. The satellite is interpreted as due to a transition in an ionized atom having an additional d hole in its valence band (nd~(-2)→n′p_(3/2)nd~(-1) transition).