Resonance ionization spectroscopy (RIS) was performed on desorbed Au, and the complete hyperfine spectrum of both isomeric and ground states of the short lived ${}_{}{}^{184}{}_{}{}^{}A\mathrm{u}$ nucleus has been recorded from the ${5d}^{10}6s{}^2{S}_{1/2}\to {5d}^{10}6p{}^2{P}_{3/2}$ optical transition. The nuclear moments of both states and the mean square charge radius changes were measured. The magnetic moments were determined to be ${\mu }_{I=5\mathrm{}}^{184g}=+2.07\mathrm{}\left(2\right){\mu }_N$ and ${\mu }_{I=2\mathrm{}}^{184m}=+1.44\mathrm{}\left(2\right){\mu }_N$ and the spectroscopic quadrupole moments to be $Q_s^{184g}=+4.65\mathrm{}\left(26\right)b$ and $Q_s^{184m}=+1.90\mathrm{}\left(16\right)\mathrm{b}$. A difference in the mean square charge radius $\delta 〈r_c^2{〉}^{184g,184m}=-0.036\mathrm{}\left(3\right){\mathrm{fm}}^2$ was found.

• Received 21 April 1997

DOI:https://doi.org/10.1103/PhysRevLett.79.2213