Innovative device to measure the energy of therapeutic proton beams

The energy measurement is based on the mean time of flight required by single beam protons to travel a distance between two detectors. In the prototype thin silicon sensors optimized for high resolution timing measurements are mounted on a mechanical system that allows the movement of one detector to change the relative distance and for the alignment along the beam direction. A calibration procedure, based on time of flight measurements at different distances and beam energies, and on the micrometric measure of the position offsets, allows to determine the unknown parameters of the system. With respect to existing technology for fast energy verification based on the beam penetration depth and requiring calibration with respect to reference systems, the proposed device provides a direct and absolute energy measurement, with similar or better speed and precision. In addition, the proposed device can be used for on-line beam measurements without perturbing the beam.

• Direct and absolute energy measurement independent of calibration with reference devices
• The energy measurement does not intercept the beam.
• Possibility to measure the energy in real time during the treatment
• Speed, precision and simplicity

Filing date: 30/09/2019

Application number: 102021000025190