Speaker
Description
The new generation of radioactive ion beam facilities will allow the production of unstable nuclei far away from the valley of stability. In the very neutron-rich region, the beta-decay energy window is much larger than the neutron separation energy of the daughter nucleus. Thus, delayed neutron emission after beta decay becomes a prevalent decay mode. To obtain information about the nuclear structure of these nuclei, precise spectroscopic measurements of beta-delayed neutrons are essential. The Neutron dEtector with Xn Tracking (NEXT) array has been designed to measure neutron energies via the time-of-flight technique with improved precision [1]. A single NEXT module is composed of a highly segmented plastic scintillator bar and position-sensitive photomultipliers. This design enables the localization of the neutron interaction point, reducing the uncertainties associated with neutron time-of-flight measurement without sacrificing the neutron detection efficiency.
The NEXT prototyping phase has already been completed, and the construction of 40 NEXT modules is ongoing. The array will be fully implemented by fall 2022. We will present NEXT construction status along with key results from characterization measurements. Details on the readout electronics will also be covered.
[1] J. Heideman et al., Nucl. Instrum. Methods Phys. Res., Sect. A 946, 162528 (2019).