NEDA: a Neutron Detector for SPIRAL2
J. J. Valiente Dobon et al.
NEDA will be an ancillary detector, coupled to a set of germanium-based gamma detectors (ex. AGATA, EXOGAM2). It will be used in different studies of nuclear structure of both neutron-rich and neutron-deficient nuclei. NEDA will present a high efficiency for one neutron and two neutrons events, a good neutron-gamma discrimination, and also it will be possible to measure the energy of the neutrons, on the basis of their flight time.
In the framework of the European Project SPIRAL2 Preparatory Phase, a group of scientists from INFN (Italy), University of Uppsala (Sweden), COPIN (Poland), CNRS (France), Turkey and Spain, have work on simulations, with the GEANT4 code, of all the processes that occur during the interaction of a neutron with the scintillator material of the detector, which is crucial to understand the detector.
In parallel, two types of liquid scintillator are investigated. The study of light production in these scintillators is used to constrain the design of the NEDA array. There is also ongoing a research on the use of digital electronics, Pulse-Shape-Analysis codes and on the read-out system of the liquid scintillator. On this latter point, the NEDA team is considering the use of photodiodes instead of the traditional photomultipliers.