The polysiloxane-based scintillator for measurements of fast neutron spectra in nuclear physics experiments

Next generation radioactive ion beam (RIB) facilities among which the SPES facility in construction at INFN-LNL require selective detection apparatuses of high resolution and efficiency as well as high granularity and then the highest covering of the solid angle. On this line the fast neutron detection still represents an uneasy task. Among the organic scintillators, the new polysiloxane-based scintillators have appealing features for measurements of neutron spectra in RIBs applications. In this work a prototype of polysiloxane-based scintillator was fully tested to gamma, alfa and neutron radiation. The scintillator calibration was studied by comparing more than one method and the pulse shape discrimination capabilities were appropriately assessed. Three fast neutron spectra were produced at the INFN-LSN tandem accelerator by means of the 7Li(p,n)7Be reaction at different energies of the incident protons. The measurements of the produced neutron yield together with theoretical estimations based on FLUKA simulations allowed first measurements of the detection efficiency. The fast response, non-toxicity, non-flammability, cheapness and high radiation resistance together with good efficiency and pulse shape capabilities make these scintillators an interesting detector for fast neutron spectroscopy in applications with RIBs.