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The structure of the 11 / 2 1 + state in 131Sb was investigated at the LOHENGRIN spectrometer of Institut Laue-Langevin via neutron-induced fission of 235U and lifetime measurements, yielding T 1 / 2 = 3 ( 2 ) , at the edge of the sensitivity of the experimental method. This first result for the 11 / 2 1 + state half-life in neutron-rich Sb isotopes provides a quadrupole reduced transition probability to the ground state of B ( E 2 ) = 1.4 − 0.6 + 1.5 W.u., very close to the B ( E 2 ; 2 1 + → 0 1 + ) in 130Sn. Realistic shell-model calculations reproduce well both the experimental level scheme of 131Sb and the B ( E 2 ; 11 / 2 1 + → 7 / 2 1 + ) value, indicting a dominant 2 + ( 130 Sn ) ⊗ π g 7 / 2 core-proton coupled configuration for the 11 / 2 1 + state.

Lifetimes of low-spin excited states in $^{112}\mathrm{Pd}$ were measured using the recoil-distance Doppler-shift technique. The nucleus of interest was populated in a $^{110}\mathrm{Pd}(^{18}\mathrm{O},^{16}\mathrm{O})^{112}\mathrm{Pd}$ reaction using the Cologne FN Tandem accelerator. Three lifetimes of ground-state band members and one lifetime of the $\ensuremath{\gamma}$ band were measured. From these lifetimes reduced transition probabilities were extracted and compared to interacting boson model, $\ensuremath{\gamma}$-soft calculations, and Davydov calculations. The lifetime of the ${2}_{\ensuremath{\gamma}}^{+}$ gives some insights on the nuclear shape and structure of the $\ensuremath{\gamma}$ band. The deduced transition rates show an indicator for a rigid triaxial nucleus as well as more indicators for a $\ensuremath{\gamma}$-soft nucleus.

The level lifetimes of the $$2_1^+$$ 2 1 + and $$4_1^+$$ 4 1 + states in $$^{182}\hbox {Pt}$$ 182 Pt have been re-measured employing the $$\gamma $$ γ –$$\gamma $$ γ fast-timing technique using fast $$\hbox {LaBr}_3$$ LaBr 3 (Ce) scintillators. Excited states in the nucleus of interest were populated by the fusion-evaporation reaction $$^{170}\hbox {Yb}(^{16}\hbox {O},\hbox {4n})^{182}\hbox {Pt}$$ 170 Yb ( 16 O , 4n ) 182 Pt at a beam energy of 87 MeV provided by the FN Tandem accelerator of the University of Cologne. The lifetime of the $$2_1^+$$ 2 1 + state was re-measured with high accuracy to be $$\tau = 563(12)~$$ τ = 563 ( 12 ) ps and resolves inconsistencies from previous measurements. Experimental results are compared to theoretical calculations in the framework of the sd-IBM with and without configuration mixing.

The $5/{2}_{1}^{\ensuremath{-}}$, $9/{2}_{1}^{\ensuremath{-}}$, and $11/{2}_{1}^{\ensuremath{-}}$ states in $^{209}\mathrm{Po}$ were populated in the $\ensuremath{\beta}$ decay of $^{209}\mathrm{At}$ and their lifetimes measured using the electronic $\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}$ fast timing technique. The lifetime of the $9/{2}_{1}^{\ensuremath{-}}$ state is measured for first time. The lifetime of the $5/{2}_{1}^{\ensuremath{-}}$ is measured to be shorter than the value adopted in the literature while the lifetime of the $11/{2}_{1}^{\ensuremath{-}}$ state agrees well with the previous measurement. In order to get deeper insight into the structure of the states, a shell-model calculation was carried out adopting a microscopic effective interaction derived from the realistic CD-Bonn potential. The comparison between theoretical and experimental data for the low-lying negative-parity states of $^{209}\mathrm{Po}$ supports the reliability of the predicted wave functions, which are found to be dominated by the coupling of a neutron hole to the yrast states of $^{210}\mathrm{Po}$. However, it also points to the important role played by minor wave-function components in describing the reduced electromagnetic strengths, suggesting the need of additional configuration mixing for achieving a better quantitative agreement.

Lifetimes of low-spin excited states in $^{98}$Zr were measured using the recoil-distance Doppler-shift technique and the Doppler-shift attenuation method. The nucleus of interest was populated in a $^{96}$Zr($^{18}$O,$^{16}$O)$^{98}$Zr two-neutron transfer reaction at the Cologne FN Tandem accelerator. Lifetimes of six low-spin excited states, of which four are unknown, were measured. The deduced $B(E2)$ values were compared with Monte Carlo shell model and interacting boson model with configuration mixing calculations. Both approaches reproduce well most of the data but leave challenging questions regarding the structure of some low lying states., Comment: 13 pages, 12 figures, 3 tables, accepted for publication in Physical Review C

Lifetimes of low- and high-spin states in the odd-A nucleus Hf-177 were measured during the EXILL&FATIMA campaign using a spectrometer equipped with eight HPGe-Clover detectors and 16 fast-timing LaBr3(Ce) detectors. For the determination of lifetimes in the pico- to nanosecond regime, the well-established generalized centroid difference method was used. Lifetimes of the 9/2(-), 9/2(+), 11/2(-), 11/2(+) states were remeasured, the lifetimes of the 13/2(-), 17/2(-), 13/2(+), 15/2(+), and 17/2(+) states were determined for the first time and an upper limit for the 19/2(+) state has been established. From these lifetimes absolute reduced transition probabilities were extracted and compared to particle-rotor-model calculations and quasiparticle-phonon-model calculations showing the importance of including multipole-multipole interactions in the description of odd-A nuclei in the rare earth region.

Lifetimes of low-lying yrast states in $^{162}\mathrm{Er}$ are measured using the electronic $\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}$ fast-timing technique. Excited states were populated in a $^{154}\mathrm{Sm}(^{12}\mathrm{C},4n)^{162}\mathrm{Er}$ fusion-evaporation reaction and $\ensuremath{\gamma}$ rays were detected in a combined setup of high purity germanium and ${\mathrm{LaBr}}_{3}$(Ce) scintillation detectors. The lifetimes of the ${4}_{1}^{+}$ and ${6}_{1}^{+}$ states are determined for the first time and the lifetimes of the ${2}_{1}^{+}$ and ${7}^{\ensuremath{-}}$ states are remeasured with higher precision. Reduced transition probabilities are extracted and well reproduced by theoretical calculations in the framework of the confined $\ensuremath{\beta}$ soft model and the interacting boson model.

Lifetimes of excited states in $^{211}\mathrm{At}$ were measured using the electronic $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ fast timing technique. The nucleus of interest was populated in a $^{208}\mathrm{Pb}(^{6}\mathrm{Li},3n)^{211}\mathrm{At}$ fusion-evaporation reaction at the FN Tandem accelerator of the Institute for Nuclear Physics, University of Cologne. The lifetimes of the $17/{2}_{1}^{\ensuremath{-}}$ and $23/{2}_{1}^{\ensuremath{-}}$ states were determined, together with an upper limit for the $13/{2}_{1}^{\ensuremath{-}}$ state. The experimental results are compared to two shell-model calculations, one using a semiempirical interaction for three particles in a single $j=9/2$ shell and the other using the modified Kuo-Herling interaction in a multi-$j$ model space.

In this study we present the preliminary results about the lifetimes of the 2 2 + , 4 1 + states of 208Po and the upper limit of the lifetime of the 2 1 + state. For measuring the lifetimes of the 2 1 + and 4 1 + states the Recoil Distance Doppler Shift (RDDS) method and for the lifetime of the 2 2 + state the Doppler Shift Attenuation method (DSAM) were used. The resulting absolute transition strength B ( M 1 ; 2 2 + → 2 1 + ) ≥ 0.122 ( 20 ) μ N 2 reveals the predominant isovector nature of the 2 2 + state of 208Po.

A new portable x-ray fluorescence (XRF) screening tool was evaluated for its effectiveness in arsenic (As) quantification in human finger and toe nails ([Formula: see text]). Nail samples were measured for total As concentration by XRF and inductively coupled plasma-mass spectrometry (ICP-MS). Using concordance correlation coefficient (CCC), kappa, diagnostic sensitivity (Sn) and specificity (Sp), and linear regression analyses, the concentration of As measured by XRF was compared to ICP-MS. The CCC peaked for scaled values of fingernail samples, at 0.424 (95% CI: 0.065-0.784). The largest kappa value, 0.400 (95% CI: -0.282-1.000), was found at a 1.3 μg g(-1) cut-off concentration, for fingernails only, and the largest kappa at a clinically relevant cut-off concentration of 1.0 μg g(-1) was 0.237 (95% CI: -0.068-0.543), again in fingernails. Analyses generally showed excellent XRF Sn (up to 100%, 95% CI: 48-100%), but low Sp (up to 30% for the same analysis, 95% CI: 14-50%). Portable XRF shows some potential for use as a screening tool with fingernail samples. The difference between XRF and ICP-MS measurements decreased as sample mass increased to 30 mg. While this novel method of As detection in nails has shown relatively high agreement in some scenarios, this portable XRF is not currently considered suitable as a substitute for ICP-MS.

We report on systematic - fast-timing measurements by using four cylindrical 1.5 LaBr(Ce) scintillator detectors which were installed in compact geometry around the focal plane of the Lohengrin fission-fragment separator at the Institut Laue–Langevin in Grenoble, France. Unconventional -ray sources as 185Os and 187W were produced by thermal-neutron activation to provide nearly prompt low-energy and K-X rays with average - and X-ray multiplicity equal to two. Due to practically no contribution of Compton background, highly precise results of time-walk measurements down to 40 keV are presented. Timing deviations related to different phenomena have been investigated, such as the geometry of an extended -ray source and the detector arrangement, long-term timing shifts and the timing contributions of the Compton background and the inter-detector Compton-scattering. The geometrical timing deviations are shown to be minimized using a multi-element detector array with a centrally symmetric arrangement relative to the center of the focal plane. Time-correction formula are proposed as analytical corrections for long-term time shifts, the time contributions of the Compton background and the position-dependent change of the time walk for cases where the calibration source cannot be placed at the center of the focal plane.