Magnetic Moments and Quadrupole-Moment Ratios of the First Excited States inW182,184,186

Abstract

The magnetic and quadrupole hyperfine interactions of the first excited $2^{+}$ states in even-$A$ tungsten nuclei have been studied in Mössbauer transmission experiments. Using the NMR result for the internal field at the W nuclei in an Fe host matrix of 630±13 kG, the $g$ factors are $g^{182}=0.266\mathrm{}\pm 0.009$, $g^{184}=0.295\mathrm{}\pm 0.010$, and $g^{186}=0.312\mathrm{}\pm 0.011$. These results are in good agreement with recent calculations of Prior and Nilsson. For the diagonal matrix elements of the quadrupole-moment operator we have obtained ${Q_{22}}^{182}:{Q_{22}}^{184}:{Q_{22}}^{186}=1:0.94\mathrm{}\pm 0.02:0.88\pm 0.02$. These ratios are nearly equal to the ratios of the corresponding transition matrix elements ${Q_{02}}^{182}:{Q_{02}}^{184}:{Q_{02}}^{186}=1:0.95\mathrm{}\pm 0.01:0.90\pm 0.01$, evaluated from recent Coulomb-excitation experiments. These results are in good agreement with the rotational model. They are somewhat at variance with the results of the microscopic calculations by Kumar and Baranger.