Design and performance of the prototype of the new Particle Identification system for the MAGNEX spectrometer within the NUMEN project

Abstract: The MAGNEX large acceptance magnetic spectrometer is installed at the Laboratori Nazionali del Sud of the Istituto Nazionale di Fisica Nucleare (INFN-LNS) in Catania. In the past, MAGNEX experimental campaigns were performed using ion beams up to $10^{10}$ pps provided by the Superconducting Cyclotron (SC) accelerator. Nevertheless, in the context of the NUMEN (Nuclear Matrix Elements for Neutrinoless double beta decay) project, which aims to get accurate values of the tiny Double Charge Exchange (DCE) cross-sections for a large number of nuclei of interest for the neutrinoless double beta decay (0$\nu\beta\beta$), the SC is being fully refurbished featuring ion beams with energies from 15 up to 70 MeV/u and intensities up to $10^{13}$ pps. The high rate of incident particles demands a complete upgrade of the MAGNEX detectors, which will consist of a new Particle Identification (PID) system and a new gas tracker detector along with a $\gamma$-calorimeter. The PID system is equipped with a large number (720) of Silicon Carbide-Cesium Iodide (Tallium doped) telescopes. A prototype of the PID wall has been built and studied thanks to an experimental test with an $^{18}$O beam at 275 MeV incident energy performed at INFN-Laboratori Nazionali di Legnaro, Italy. In this manuscript, the design of the new PID system, the in-beam test experimental set-up, and the prototype's performances are presented.