M Spectra of Elements 39 ≤ Z ≤ 56 Measured with an Ultra-Thin Window Si(Li) Detector

Abstract.

 Elements in the range 39 ≤ Z ≤ 56 were excited by electrons of an energy between 3 and 15 keV. The X-rays were detected by means of an energy dispersive Si(Li) spectrometer with an ultra-thin polymer entrance window. In all cases M_ζ = M₅N₃ was found to be the most intense M line. Thus, the relative intensity of this line is by definition 100%. For the heavier of the investigated elements some other M lines were observed: M₅O₃, M_γ and M₂N₄. M_γ was detectable for Z ≥ 47, starting with a relative intensity of about 5%, which increased rapidly with Z to approximately 10%. M₅O₃ was first observed for 49-In, with a relative intensity of less than 10%, which increased up to approximately 50% for 56-Ba. Also, M₂N₄ was observed for Z ≥ 49. The relative intensity of that line is approximately one half of that of M_γ.