Design and First Operation of a Silicon-based Non–invasive Beam Monitor

Non–invasive, highly accurate and reliable beam monitors are a desired aim of any beam diagnostics design. Knowledge of beam parameters is essential in fundamental research, industrial or medical applications with varying demands. It’s also extremely critical in the optimization of ion beams used for cancer treatment. Ocular tumour treatment at the Clatterbridge Cancer Centre (CCC) uses a 60 MeV proton beam. Disturbances introduced to a beam by intercepting devices risk affecting its energy and deteriorating the energy spread, thereby limiting the effectiveness of the treatment. The advantageous semi-circular structure of the LHCb Vertex Locator (VELO) detector has been investigated in the QUASAR Group as an interesting option for a noninvasive online beam monitor. The method relies on beam ‘halo’ measurements without disturbing the part of the beam used for treatment. This contribution discusses the measurement method, setup design and integration within the CCC treatment beam line and outlines the preliminary experimental results of the performance of the monitor.