Experimental Study and Quantitative Analysis of the Stability of Physical Parameters of the Scanning Beam Delivery System in a Proton Therapy Facility

We present the results of a quantitative study of inaccuracies in beam delivery by a proton therapy system, which were used to determine the planned amount of irradiation. A technique for measuring and analyzing the physical parameters of a proton beam is described. Calculated is the minimum deviation from the clinical treatment volume required to ensure its coverage with the prescribed dose, taking into account beam delivery errors by a proton therapy system; sufficiency of the calculated deviation is assessed. The results of the study make it possible to optimize the determination of the planned irradiation amount in proton therapy.