Measurement of the Coulomb-capture ratio of muons in binary solid solutions of metals

The Coulomb-capture ratios of muons in the metallic solid solutions Au-Ag, Te-Se, Cd-Mg, Nb-V, and Cu-Ni have been measured via the muonic Lyman series intensities. In the case of Nb-V, targets of three stoichiometric ratios were investigated. The results do not agree with the per-atom ratios A(Z/Z′) assumed to be equal to Z/Z′ ("Fermi-Teller law") or (Z/Z′)^7/6. They are better, but also not in general well, reproduced by A(Z/Z′)=Z^1/3 ln(0.57 Z)/[(Z′)^1/3 ln(0.57 Z′)], deviations occuring in cases of different metallic radii.