Compton electrons' tracking within a single silicon layer with controlled-drift detectors

The relatively small doppler broadening of silicon and the excellent energy and position resolution of Controlled-Drift Detectors make these detectors suitable candidates as scatter detectors that allow reconstruction of the orginal location of the gamma-ray with ultimate position resolution. The achievable performance of such detectors allow imaging the 2D projection of the electron track and its ionization profile by sampling the charge desposted in each pixel. This feature would allow electron tracking not only for those electrons crossing more detection layers but also for low energy electrons, often totally absorbed in the interaction layer owing to the short electron range. The p0rojection of the initial direction of the recoil electron, the vertex of the interaction and the electron energy can therefore be more precisely estimate for wide range of Compton electron energies leading to improved resolution and efficiency. The paper presentw the results of the experimental characterization of a Controlled Drift Detector prototype in order to assess its capability in Compton electron tracking.