Towards 2D dosimetry using monolithic active pixel sensors and a copper grating

Abstract Higher energy and intensity X-ray radiotherapy treatments are coming into wider use, having the benefit of requiring fewer treatment fractions hospital visits per patient. However, small percentage errors in multileaf collimator positioning dose become bigger problems with higher doses fraction. Hence, real-time verification becomes essential. Where devices downstream from patient suffer scattering patient, upstream can disturb therapeutic beam. Here, a method is proposed for performing dosimetry using monolithic active pixel sensors, which be made thin enough to beam by <1%. In order calculate tumour, device needs make measurement photon field. Some photons will Compton scatter an electron silicon generate signal. this signal obscured deposits contamination electrons, originating accelerator head air. Often extensive build-up material added reduce enhance leads degradation Instead we propose strips 50 µm thick copper grating pattern measuring difference without it. The electrons relatively undisturbed presence generated via enhanced under strips. Hence two signals mostly consists photons. From derived. ?m keep attenuation below 1%, but itself would give total response 38% electrons. Using technique, show that reduced 2.6% This allows only extracted data thus very detector calculated Monte Carlo model extrapolate flux tumour.