Nuclear spectroscopy with slow neutrons

Abstract

The aim of nuclear spectroscopy is to study nuclear excitations with a view to improving our knowledge of the forces play within the nucleus. Many complementary techniques have been developed to unravel the complex interplay of these forces and it is usually the combination of several experimental approaches such as the study of radioactive decay, transfer reactions, neutron capture, inelastic scattering, Coulomb excitation and other charged particle reactions which allows us to construct detailed level schemes and interpret them. We will concentrate, within the frame of this Workshop on the advanced instrumentation of the neutron capture gamma-ray spectroscopy, which plays an important and specific role in the comprehensive testing of nuclear models. Neutron capture gammaray spectroscopy now employs very sophisticated techniques to study nucear structure. The combination of precise measurements of primary gamma transitions with the precision obtained to data with curved and flat crystal and conversion electron spectrometers has considerably extended the possibilities in the study of nuclear structure. The nearly perfect resolution obtained with the most modern double flat crystal spectrometers allows the measurement of lifetimes of excited nuclear states in the range < 10−12 s via the observation of the Doppler broadening of gamma rays due to the recoil of the nucleus following emission of a primary gamma ray.