Abstract
In Charged Particle Therapy (PT) proton or 12C beams are used to treat deep-seated solid tumors exploiting the advantageous characteristics of charged particles energy deposition in matter. For such projectiles, the maximum of the dose is released at the end of the beam range, in the Bragg peak region, where the tumour is located. However, the nuclear interactions of the beam nuclei with the patient tissues can induce the fragmentation of projectiles and/or target nuclei and needs to be carefully taken into account when planning the treatment. In proton treatments, the target fragmentation produces low energy, short range fragments along all the beam path, that deposit a non-negligible dose especially in the first crossed tissues. On the other hand, in treatments performed using 12C, or other (4He or 16O) ions of interest, the main concern is related to the production of long range fragments that can release their dose in the healthy tissues beyond the Bragg peak. Understanding nuclear fragmentation processes is of interest also for radiation protection in human space flight applications, in view of deep space missions. In particular 4He and high-energy charged particles, mainly 12C, 16O, 28Si and 56Fe, provide the main source of absorbed dose in astronauts outside the atmosphere. The nuclear fragmentation properties of the materials used to build the spacecrafts need to be known with high accuracy in order to optimise the shielding against the space radiation. The study of the impact of these processes, which is of interest both for PT and space radioprotection applications, suffers at present from the limited experimental precision achieved on the relevant nuclear cross sections that compromise the reliability of the available computational models. The FOOT (FragmentatiOn Of Target) collaboration, composed of researchers from France, Germany, Italy and Japan, designed an experiment to study these nuclear processes and measure the corresponding fragmentation cross sections. In this work we discuss the physics motivations of FOOT, describing in detail the present detector design and the expected performances, coming from the optimization studies based on accurate FLUKA MC simulations and preliminary beam test results. The measurements planned will be also presented.
Highlights
In the last decade a continuous increase in the number of cancer patients treated with charged Particle Therapy (PT) [1] has been registered, as a consequence of its effectiveness in the treatment of deep-seated solid tumors [2]
The experiment has been designed with the main goal of investigating target fragmentation in proton therapy by means of an inverse kinematic approach, using beams of 12C, 16O impinging on graphite and polyethylene targets, to extract cross sections for the production of charged fragments in p+C and p+O collisions in the energy range of 50–200 MeV/nucleon
The same apparatus will be used to investigate the double differential cross sections of the projectile fragmentation process for beams of 4He, 12C and 16O impinging on graphite, polyethylene and PMMA targets up to 500 MeV/nucleon for charged PT and up to 800 Mev/nucleon for space radioprotection
Summary
In the last decade a continuous increase in the number of cancer patients treated with charged Particle Therapy (PT) [1] has been registered, as a consequence of its effectiveness in the treatment of deep-seated solid tumors [2]. To achieve the experimental goals a redundancy in measuring the different kinematic variables is needed, exploiting different particle identification (PID) techniques For this reason the FOOT setup includes a Time-Of-Flight (TOF) system and a calorimeter for the fragments energy measurement, that, combined with the measurement of the energy released in thin detectors and with the information provided by the magnetic spectrometer, allows the isotope mass identification. The fragment identification region is the distal part of the detector, located at least 1 m away from the target It is composed of two orthogonal planes of plastic scintillator bars (Tof-Wall detector), providing the stop of the TOF and the measurement of the energy loss, followed by a BGO calorimeter used to measure the fragment kinetic energy (see Figure 5). According to FLUKA MC simulation, 77% and 72% of the fragments produced by the interaction of the 16O (400 MeV/nucleon) beam on C and C2H4 targets, respectively, is contained inside the ES
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
