Magnetic Dipole and Electric Quadrupole Moments of the First 2+ State of Sm154

The hyperfine interactions of the first excited ${2}^{+}$ state of ${\mathrm{Sm}}^{154}$ have been measured in Sm${\mathrm{Cl}}_{3}$\ifmmode\cdot\else\textperiodcentered\fi{}6${\mathrm{H}}_{2}$O and SmIG at 4.2\ifmmode^\circ\else\textdegree\fi{}K, using the M\"ossbauer effect following Coulomb excitation. The results in Sm${\mathrm{Cl}}_{3}$\ifmmode\cdot\else\textperiodcentered\fi{}6${\mathrm{H}}_{2}$O have been used to determine the magnetic dipole and electric quadrupole moments ${\ensuremath{\mu}}^{154}=(0.778\ifmmode\pm\else\textpm\fi{}0.036){\ensuremath{\mu}}_{N}$ and ${Q}^{154}(1\ensuremath{-}R)=\ensuremath{-}1.33\ifmmode\pm\else\textpm\fi{}0.46$ b, respectively. ${\ensuremath{\mu}}^{154}$ has been used to determine ${H}_{\mathrm{eff}}=3.04\ifmmode\pm\else\textpm\fi{}0.12$ MG in SmIG at 4.2\ifmmode^\circ\else\textdegree\fi{}K. This value for ${H}_{\mathrm{eff}}$ (SmIG) agrees with the value used by Atzmony et al. to measure ${{g}_{R}}^{152}$ in SmIG; thus their value for ${{g}_{R}}^{152}$ is confirmed. An improved technique for using the M\"ossbauer effect following Coulomb excitation is reported.