Experimental characterization of a fast, pixelated CMOS sensor and design of a Recoil-Proton Telescope for neutron spectrometry

Abstract

Neutrons are particles of interest in various domains such as fundamental physics, biology, elemental analysis or radio-protection. The measurement of the neutron energy is necessary in all these domains, but the required characteristics of the spectrometers can vary greatly from an application to another. The IPHC laboratory is currently developing a new CMOS pixel Recoil Protons Telescope (RPT). This compact detector allows a real-time reconstruction of the neutron spectrum up to very high flux. The pixelated ultra-fast CMOS sensors were characterized in two proton beam experiments. This experimental characterization was then used in a realistic Monte Carlo simulation of the full system to compute the expected performances. The simulated results exhibit very good spectrometric performances, with an energy resolution better than 4% over a [4.5, 20] MeV energy range. These performances, combined with its compactness and ability to reconstruct the spectrum in real time, make it a very interesting device for various applications.