Shielding design for a proton medical accelerator facility

Agosteo, S.; Corrado, Mauro; Silari, M.; Fatis, Paola Tabarelli de

doi:10.1109/23.491521

Cited by 4 publications

(3 citation statements)

References 12 publications

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“…If the shielding target value is set at 1/2 of the legal limit set, based on the shielding design standards, persons working with radiation must not exceed 12.5 µSv/hr (25 mSv/yr) or 5µSv/hr (10 mSv/yr). Not only that, according to S. Agosteo [16], there is the claim that it should be lowered to below 1 µSv/hr (2 mSv/yr). Regarding that matter, as a result of finding out the absorbed dose rate according to the width of shielding wall in this study, if was found out that if it is lowered to below 12.5 µSv/hr (25 mSv/yr), more than 130 cm of concrete width is needed, and when lowered to below 5µSv/hr (10mSv/yr), more than 140 cm, and when lowered to below 1 µSv/hr( 2 mSv/yr), more than 160 cm of concrete width is needed, respectively.…”

Section: Discussionmentioning

confidence: 99%

“…However, neutrons cause activation by interacting with concrete [14], which leads to the generation of secondary radiation. Currently many researchers are reporting about optimized shielding of cyclotrons, according to the ALARA [15] recommendations [16,17]. Therefore, in this study, the 18 O (p, n) 18 F nuclear reaction of the medical cyclotron of 16.5 MeV was simulated using the Monte Carlo simulation, and it was intended to design a shielding wall through the monitoring of the radiation generated from a nuclear reaction and analyze the activation of the shielding wall according to the operation time of cyclotron.…”

Section: Introductionmentioning

confidence: 99%

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Design of the shielding wall of a cyclotron room and the activation interpretation using the Monte Carlo simulation

Jang

Kim

2017

J. Inst.

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Medical cyclotron is mainly a facility used for producing radiopharmaceutical products, which secondarily generate high energy radiation when producing a radiopharmaceutical product. In this study, the intention is that the reductions in spatial dose rate for the radiation generated when cyclotron is operated and the absorbed dose rate, according to the width of shielding wall, will be analyzed. The simulation planned targetry and protons of 16.5 MeV, 60µA through a Monte Carlo simulation, and as a result of the simulation, it has been found through an analysis that a concrete shielding wall of 200 cm is needed, according to the absorbed dose rate of the shielding wall thickness of cyclotron, and the concrete gives an external exposure level of 1 µSv/hr after 19 years of cyclotron operation as it is activated by the nuclear reaction of cyclotron. When taking into account the mechanical life span of cyclotron, it is deemed necessary to develop additional shielding and a low activation material.

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Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Design of the shielding wall of a cyclotron room and the activation interpretation using the Monte Carlo simulation

Jang

Kim

2017

J. Inst.

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“…In this paper, we present the design and dose calculations of a shielding system for a laseraccelerated proton radiation therapy facility. For conventional cyclotron or synchrotron based proton therapy facilities, the beam losses occurring during injection, RF capture, acceleration, transfer and delivery (Agosteo et al 1996). These processes happen at different locations; therefore, the shielding calculations have to consider each radiation source separately.…”

Section: Introductionmentioning

confidence: 99%

Shielding design for a laser-accelerated proton therapy system

Jiang

Luo²,

Fourkal³

et al. 2007

Phys. Med. Biol.

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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.

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