Isotope shift of182Hg and an update of nuclear moments and charge radii in the isotope range181Hg-206Hg

The technique of collinear fast-beam laser spectroscopy has been used to measure the isotope shifts of the even-even isotopes of Hg (Z=80) in the mass range 182≤A≤198 at the on-line mass separator ISOLDE at CERN. The atomic transition studied (6s 6p 3 P 2- 6s7s 3 S 1,λ=546.1 nm) starts from a metastable state, which is populated in a quasi resonant charge transfer process. The resulting changes in nuclear mean square charge radii show clearly that182Hg follows the trend of the heavier, even, weakly oblate isotopes. Correspondingly the huge odd-even shape staggering in the light Hg isotopes continues and the nuclear shape staggering and shape coexistence persists down to the last isotope inv…

Determination of nuclear spins of short-lived Rb and Cs isotopes by β radiation detected optical pumping

First absolute mass measurements of short-lived isotopes

Absolute mass measurements of short-lived isotopes have been performed at the on-line mass separator ISOLDE at CERN by determining the cyclotron frequencies of ions confined in a Penning trap. The cyclotron frequencies for77,78,85,86,88Rb and88Sr ions could be determined with a resolving power of 3×105 and an accuracy of better than 10−6, which corresponds to 100 keV for massA=100. The shortest-lived isotope under investigation was77Rb with a half-life of 3.7 min. The resonances obtained for the isobars88Rb and88Sr were clearly resolved.

The isotope shift of the radioactive Cd-isotopes (102?A?120) determined by on-line laserspectroscopy

Determination of nuclear spins of short-lived isotopes by laser induced fluorescence

Abstract The spins of several nuclear ground and isomeric states have been measured for a number of mercury isotopes. The fluorescent light from the 6s6p3P1 state is observed at 2537 A after excitation with the frequency doubled output of a pulse dye laser. Four different laser induced fluorescence techniques were tested for their applicability: double resonance, Hanle effect, time delayed integral Hanle beats, and time resolved quantum beats. The sensitivity and selectivity of these models are compared with emphasis on the determination of spins of nuclei far from beta-stability, where short half lives and low production yields restrict the number of available atoms. The experiments were c…

Nuclear Spins of the IsomersHg191m−185mDetermined by On-Line Quantum-Beat Spectroscopy

The nuclear spins of the very neutron-deficient $^{191m\ensuremath{-}185m}\mathrm{Hg}$ isomers were measured on line at the mass separator ISO LIDE at CERN using pulsed-laser excitation and observation of the time-resolved quantum beats from selected hyperfine-structure states. The spins of these isomers are with $I=\frac{13}{2}$ equal to those of the long-lived isomers $^{199m\ensuremath{-}193m}\mathrm{Hg}$ already known. The persistence of this spin value for eight isomers is explained by the model of rotation-aligned coupling.

Nuclear Shape Staggering in Very Neutron-Deficient Hg Isotopes Detected by Laser Spectroscopy

The isotope shifts of $^{188}\mathrm{Hg}$, $^{186}\mathrm{Hg}$, and $^{184}\mathrm{Hg}$ in the 2537-\AA{} line have been measured by use of tunable dye laser at the on-line mass separator ISOLDE at CERN. The results are $\ensuremath{\delta}\ensuremath{\nu}(^{188}\mathrm{Hg}\ensuremath{-}^{204}\mathrm{Hg})=35.8(2)$ GHz; $\ensuremath{\delta}\ensuremath{\nu}(^{186}\mathrm{Hg}\ensuremath{-}^{204}\mathrm{Hg})=39.4(2)$ GHz; and $\ensuremath{\delta}\ensuremath{\nu}(^{184}\mathrm{Hg}\ensuremath{-}^{204}\mathrm{Hg})=43.1(2)$ GHz. These data combined with those obtained by $\ensuremath{\beta}$-radiation-detected optical pumping ($\ensuremath{\beta}$-RADOP) on the odd Hg isotopes yield a huge odd-even…

Nuclear spins of76Rb and119Cs by? radiation detected optical pumping

An optical pumping apparatus has been attached to the reconstructed ISOLDE on-line mass separator at CERN in order to obtain nuclear data of isotopes far fromβ stability. As first results the spins of76Rb (T 1/2=36.8 s) and119Cs (T 1/2=37.7 s) have been determined byβ radiation detected optical pumping (β-RADOP) to beI=1 andI=9/2 respectively.