The levels in 26 Na with single particle character have been observed for the first time using the d( 25 Na,pγ) reaction at 5 MeV/nucleon. The measured

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The elusive β − p + decay was observed in 11 Be by directly measuring the emitted protons and their energy distribution for the first time with the prototype Active Target Time Projection Chamber (pAT-TPC) in an experiment performed at ISAC-TRIUMF. The measured β − p + branching ratio is orders of magnitude larger than any previous theoretical model predicted. This can be explained by the presence of a narrow resonance in 11 B above the proton separation energy.

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We report a precise determination of the 19 Ne half-life to be T 1/2 = 17.262 ± 0.007 s. This result disagrees with the most recent precision measurements and is important for placing bounds on predicted right-handed interactions that are absent in the current Standard Model. We are able to identify and disentangle two competing systematic effects that influence the accuracy of such measurements. Our findings prompt a reassessment of results from previous high-precision lifetime measurements that used similar equipment and methods.PACS numbers: 24.80.+y, 27.20.+n, 12.15.Hh, 29.40.Mc Precise measurements of decay rates and angular correlations in semi-leptonic processes are known to be excellent probes for interactions that are predicted by extensions of the Standard Model [1]. For example, the measured lifetime and electron asymmetry in neutron β decay [2] are used to probe for right-handed currents and obtain a precise value of V ud , the up-down element of the Cabibbo-Kobayashi-Maskawa quark-mixing matrix, in a relatively simple system that is free of nuclear structure effects. However, in spite of this compelling advantage, precision neutron β decay experiments are challenging. Current results from independent neutron decay measurements show large discrepancies that need to be addressed before conclusive interpretations can be made from the data [2]. In this regard Nature offers a fortuitous alternative in 19

The combination of γ-ray spectroscopy and charged-particle spectroscopy is a powerful tool for the study of nuclear reactions with beams of nuclei far from stability. This paper presents a new silicon detector array, SHARC, the Silicon Highly-segmented Array for Reactions and Coulex. The array is used at the radioactive-ion-beam facility at TRIUMF (Canada), in conjunction with the TIGRESS γ-ray spectrometer, and is built from custom Si-strip detectors utilising a fully digital readout. SHARC has more than 50% efficiency, approximately 1000-strip segmentation, angular resolutions of ∆θ ≈ 1.3 deg and ∆φ ≈ 3.5 deg, 25-30 keV energy resolution, and thresholds of 200 keV for up to 25 MeV particles. SHARC is now complete, and the experimental program in nuclear astrophysics and nuclear structure has commenced.

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Many-body nuclear theory utilizing microscopic or chiral potentials has developed to the point that collectivity might be dealt with in an ab initio framework without the use of effective charges; for example with the proper evolution of operators, or alternatively, through the use of an appropriate and manageable subset of particle-hole excitations.We present a precise determination of E2 strength in 22 Mg and its mirror 22 Ne by Coulomb excitation, allowing for rigorous comparisons with theory. No-core symplectic shell-model calculations were performed and agree with the new B(E2) values while in-medium similarity-renormalization-group calculations consistently underpredict the absolute strength, with the missing strength found to have both isoscalar and isovector components.