Precision beam telescope based on SOI pixel sensor technology for electrons in the energy range of sub-GeV to GeV

Abstract

Abstract We developed a beam telescope system comprising five layers of 300 μm thick INTPIX4NA monolithic pixel sensors, each with a pixel size of 17 μm square. The sensors were fabricated using silicon-on-insulator (SOI) technology. The signal-to-noise ratio of 140–230 is realized at a bias voltage of 20 V. The tracker system was tested using a positron beam of 200–822 MeV/c, and various tracking methods are examined to optimize the spatial precision achievable at these energies. The best tracking precision including the precision of the sensor under test itself is 11.04 ± 0.10 μm for 822 MeV/c positrons for an equidistant sensor spacing of 32 mm. The achieved precision results combined with the intrinsic spatial resolution value obtained for a similar system using 120 GeV protons are used to estimate the tracking performance of electrons in the GeV energy range; a tracking precision of 2.22 μm is evaluated for 5 GeV electrons. The method to estimate the tracking performance is verified using a Geant4-based simulation. The developed high-precision tracker system enables us to map the detailed performance of sensors with pixel sizes of $\mathcal {O}$(10 μm) and will therefore be a powerful system for the development of devices targeting precision position resolutions.