Proton irradiation for quality assurance of ATLAS18 strip sensors using the Birmingham MC40 cyclotron

The Birmingham MC40 Cyclotron is used to perform proton irradiations of silicon detector devices as part of the ongoing ATLAS ITk Strip Sensor Quality Assurance program. It provides a dedicated beamline delivering 27 MeV protons at currents up to a few μ A. Samples are placed within a thermally controlled box, held below −20 °C, which can be scanned across the beam in two directions, by means of two motorised stages. Recently, upgrades have been performed to the sample scanning system, including new motor stages and improved control software. These upgrades have allowed increases to the scanning speed and beam current, leading to faster irradiations. Fluences of 1 . 6 × 1 0 15 n eq / cm 2 , the maximum expected lifetime fluence for ITk strip sensors, can now be delivered to sensors at a rate of over 4 cm 2 /h, double what was previously possible.