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Shielding design for a laser-accelerated proton therapy system.
| Content Provider | Semantic Scholar |
|---|---|
| Author | Fan, Jiajin Luo, Wei Fourkal, Eugene Lin, Tao Li, Jinsheng Veltchev, Iavor |
| Copyright Year | 2007 |
| Abstract | In this paper, we present the shielding analysis to determine the necessary neutron and photon shielding for a laser-accelerated proton therapy system. Laser-accelerated protons coming out of a solid high-density target have broad energy and angular spectra leading to dose distributions that cannot be directly used for therapeutic applications. A special particle selection and collimation device is needed to generate desired proton beams for energy- and intensity-modulated proton therapy. A great number of unwanted protons and even more electrons as a side-product of laser acceleration have to be stopped by collimation devices and shielding walls, posing a challenge in radiation shielding. Parameters of primary particles resulting from the laser-target interaction have been investigated by particle-in-cell simulations, which predicted energy spectra with 300 MeV maximum energy for protons and 270 MeV for electrons at a laser intensity of 2 x 10(21) W cm(-2). Monte Carlo simulations using FLUKA have been performed to design the collimators and shielding walls inside the treatment gantry, which consist of stainless steel, tungsten, polyethylene and lead. A composite primary collimator was designed to effectively reduce high-energy neutron production since their highly penetrating nature makes shielding very difficult. The necessary shielding for the treatment gantry was carefully studied to meet the criteria of head leakage <0.1% of therapeutic absorbed dose. A layer of polyethylene enclosing the whole particle selection and collimation device was used to shield neutrons and an outer layer of lead was used to reduce photon dose from neutron capture and electron bremsstrahlung. It is shown that the two-layer shielding design with 10-12 cm thick polyethylene and 4 cm thick lead can effectively absorb the unwanted particles to meet the shielding requirements. |
| Starting Page | 021107 |
| Ending Page | 021107 |
| Page Count | 1 |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | https://astro.temple.edu/~tuf32192/pap_all/papers/PMB52_3913.pdf |
| PubMed reference number | 17664585v1 |
| Volume Number | 52 |
| Issue Number | 13 |
| Journal | Physics in medicine and biology |
| Language | English |
| Access Restriction | Open |
| Subject Keyword | Collimator Device Component Electrons Extravasation Gantry Intraoral radiation shield Monte Carlo Method Neutrons Particle Photons Polyethylene Proton Therapy Proton-Translocating ATPases Protons Sample Variance Shield Device Component Stainless Steel Walls of a building tungsten |
| Content Type | Text |
| Resource Type | Article |
