Electron density resolution determination and systematic uncertainties in proton computed tomography (pCT)

The use of protons in radiotherapy offers a very precise and effective tool for malignant tumor treatment. In order to fully exploit the benefits of proton therapy, a precise determination of the proton range inside the patient is needed. Currently, this information is provided by conventional X-ray CT. In our work, we explore the theoretical limits of proton CT by means of Monte Carlo simulations. We focus on the accuracy in determining the electron density of different clinical relevant materials and the systematic uncertainties that influence the measurement with an ideal cone beam proton CT scanner.