ΔE–E Telescope for the Detection of Charged Particles Based on a Si Detector and a SiPM Array with Scintillation Crystals

Abstract

The characteristics of a ΔE–E telescope, which is planned to be used in the experimental setup focused on few-nucleon reactions, are studied. The required parameters of the ΔE–E telescope were determined on the basis of the numerical modeling of probable reactions. The telescope comprises a ΔE detector, which is a totally depleted surface-barrier silicon detector with a diameter of 8 mm and a thickness of ~24 μm, and an E detector based on LFS-8 crystals and a 16-element SiPM ARRAYC-30035-16P-PCB array. The telescope is designed, in particular, for coincidence detection of two charged particles emitted at close angles. This is made possible by the matrix structure of the E detector. The time resolution of the ΔE detector and the time and amplitude resolutions of all cells of the E detector were determined. The standard method of detection of two γ quanta from the beta decay of ²²Na was used to measure the time resolution. Time coincidences of signals from the ΔE detector and a neutron detector based on a liquid scintillator (EJ-301) with its FWHM no worse than 1 ns were obtained. Similar measurements for the E-detector cells revealed time (less than 0.6 ns) and amplitude (~15% at an energy of ~1 MeV) resolutions that satisfy the experimental requirements for particle sorting and determination of their energy. The intrinsic background of the E detector, which arises from the radioactivity of LFS-8 crystals, was measured. The relative number of events corresponding to simultaneous triggering of two or more E-detector cells irradiated with α particles from a ²²⁶Ra source was also determined. This value may help estimate the number of random coincidences in a real experiment.