Precision measurements in nuclear β ‐decay with LPCTrap
The experimental achievements and the current program with the LPCTrap device installed at the LIRAT beam line of the SPIRAL1‐GANIL facility are presented. The device is dedicated to the study of the weak interaction at low energy by means of precise measurements of the β−ν angular correlation parameter. Technical aspects as well as the main results are reviewed. The future program with new available beams is briefly discussed.
The electron-neutrino angular correlation in beta decay of helium 6
Abstract The electron-neutrino angular correlation in decay of He6 has been determined by measuring the distribution of electron energies and recoil velocities without selection of angle. The correlation parameter α was found to be −0.353−0.053+0.033, confirming current belief that the Gamow-Teller interaction is of axial vector type. The maximum admixture of a tensor interaction is given by |CT|2/|CA|2
Impact of Nuclear Data Uncertainties on Transmutation of Actinides in Accelerator-Driven Assemblies
Abstract The potential impact of nuclear data uncertainties on a large number of performance parameters of reactor cores dedicated to the transmutation of radioactive wastes is discussed. An uncertainty analysis has been performed based on sensitivity theory, which underlines the cross sections, the energy range, and the isotopes that are responsible for the most significant uncertainties. To provide guidelines on priorities for new evaluations or validation experiments, required accuracies on specific nuclear data have been derived, accounting for target accuracies on major design parameters. The required accuracies (mostly in the energy region below 20 MeV), in particular for minor actinide data, are of the same order of magnitude of the achieved accuracies on major actinides. Specific requirements also concern the improvement of minor actinide data related to decay heat and effective delayed-neutron fraction assessment.