Upgraded readout electronics for the Neutron dEtector with Xn Tracking (NEXT) array*

The advent of the new generation of radioactive ion beam facilities will enable studies of very neutron-rich nuclei near the drip line. In these regions, beta-delayed neutron emission becomes a dominant decay channel, and neutron spectroscopy is a powerful tool to elucidate the nuclear structure. The Neutron dEtector with Xn Tracking (NEXT) array has been developed for more precise time-of-flight measurements of neutrons [1]. A single NEXT module is composed of thin plastic scintillator bars and position-sensitive photomultipliers, and this design enables the localization of neutron interaction points for better energy resolution.

Since the initial design phases of NEXT prototypes [1], the readout electronics have been continuously upgraded, aiming at the full implementation of the NEXT array, which requires dedicated high-density triggering and readout schemes. Along with details on the upgrade, results from proof-of-principle measurements using the new electronics will be presented.

[1] J. Heideman et al., Nucl. Instrum. Methods Phys. Res., Sect. A 946, 162528 (2019).