M2,3Emission Band of Copper

The copper $M_{2,3}$ band was investigated in connection with a sequential study of the $M_{2,3}$ emission and absorption spectra of the $3d$ transition metals. The characteristic band is superimposed on a continuous spectrum emitted by the target and the paper describes the procedure for removing the effect of this background. Other experimental considerations dealing with such effects as the instrumental window, self-absorption, the presence of contaminants, and the nature of the target layer are included. Where possible, an assessment is made of the distortion produced by such factors in the shape of the band. The photo-metrically determined $M_{2,3}$ intensity contour is compared with recent work based on detection schemes utilizing photon counters. On the basis of certain assumptions the composite $M_{2,3}$ distribution is decomposed into individual $M_2$ and $M_3$ curves, whose behavior at the high-energy end of the spectrum is in good agreement with previously available data on the individual absorption edges. Features of the $\frac{I\left(E\right)\mathrm{}}{{\nu }^2}$ distribution belonging to the $M_3$ band are as follows: the band has a maximum at 72.0 ev (172 A) and excluding satellite structure and tailing effects has a width of 7.8 ev. At the high-energy end, the intensity rises gradually and no sharp structures are noticeable. Except for the satellite structure, no inconsistencies arise when the results on the $M_3$ band ($\mathrm{valence}\to 3p$) are compared with those on the $L_3$ band ($\mathrm{valence}\to 2p$).