A. Diaz Varela

Far from 'Easy' Spectroscopy with the 8π and GRIFFIN Spectrometers at TRIUMF-ISAC

The 8 pi spectrometer, installed at the TRIUMF-ISAC facility, was the worlds most sensitive gamma-ray spectrometer dedicated to beta-decay studies. A description is given of the 8 pi spectrometer and its auxiliary detectors including the plastic scintillator array SCEPTAR used for beta-particle tagging and the Si(Li) array PACES for conversion electron measurements, its moving tape collector, and its data acquisition system. The recent investigation of the decay of Cs-124 to study the nuclear structure of Xe-124, and how the beta-decay measurements complemented previous Coulomb excitation studies, is highlighted, including the extraction of the deformation parameters for the excited 0(+) bands in Xe-124. As a by-product, the decay scheme of the (7(+)) Cs-124 isomeric state, for which the data from the PACES detectors were vital, was studied. Finally, a description of the new GRIFFIN spectrometer, which uses the same auxiliary detectors as the 8 pi spectrometer, is given.

Two-neutron transfer reaction mechanisms in 12 C(6 He, 4 He) 14 C using a realistic three-body 6 He model

The reaction mechanisms of the two-neutron transfer reaction 12C(6He,4He) have been studied at Elab=30 MeV at the TRIUMF ISAC-II facility using the Silicon Highly-segmented Array for Reactions and Coulex (SHARC) charged-particle detector array. Optical potential parameters have been extracted from the analysis of the elastic scattering angular distribution. The new potential has been applied to the study of the transfer angular distribution to the 2+2 8.32 MeV state in 14C, using a realistic three-body 6He model and advanced shell-model calculations for the carbon structure, allowing to calculate the relative contributions of the simultaneous and sequential two-neutron transfer. The reaction model provides a good description of the 30-MeV data set and shows that the simultaneous process is the dominant transfer mechanism. Sensitivity tests of optical potential parameters show that the final results can be considerably affected by the choice of optical potentials. A reanalysis of data measured previously at Elab=18 MeV, however, is not as well described by the same reaction model, suggesting that one needs to include higher-order effects in the reaction mechanism.

High-precision Half-life And Branching Ratio Measurements For Superallowed β+ Emitters At TRIUMF-ISAC

High precision measurements of the

Investigating the nature of the Er isotopes with ( p , t ) reactions

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Halo-induced large enhancement of soft dipole excitation of 11 Li observed via proton inelastic scattering

values for superallowed Fermi

2 1 + to 3 1 + γ width in Na 22 and second class currents

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21+ to 31+ γ width in Na22 and second class currents

transitions between

21+ to 31+ γ width in Na 22 and second class currents 21+ to 31+ γ WIDTH in Na 22 ⋯ S. TRIAMBAK et al.

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High-precision half-life measurement for the superallowed Fermi β+ emitter Mg22

isobaric analogue states allow for stringent tests of the electroweak interaction described by the Standard Model. These transitions provide an experimental probe of the Conserved-Vector-Current hypothesis, enable the most precise determination of the up-down (

Mapping quadrupole collectivity in the Cd isotopes: The breakdown of harmonic vibrational motion

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