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Böhlen TT, Germond JF, Desorgher L, Veres I, Bratel A, Landström E, Engwall E, Herrera FG, Ozsahin EM, Bourhis J, Bochud F, Moeckli R. Very high-energy electron therapy as light-particle alternative to transmission proton FLASH therapy - An evaluation of dosimetric performances. Radiother Oncol 2024; 194:110177. [PMID: 38378075 DOI: 10.1016/j.radonc.2024.110177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Revised: 01/29/2024] [Accepted: 02/16/2024] [Indexed: 02/22/2024]
Abstract
PURPOSE Clinical translation of FLASH-radiotherapy (RT) to deep-seated tumours is still a technological challenge. One proposed solution consists of using ultra-high dose rate transmission proton (TP) beams of about 200-250 MeV to irradiate the tumour with the flat entrance of the proton depth-dose profile. This work evaluates the dosimetric performance of very high-energy electron (VHEE)-based RT (50-250 MeV) as a potential alternative to TP-based RT for the clinical transfer of the FLASH effect. METHODS Basic physics characteristics of VHEE and TP beams were compared utilizing Monte Carlo simulations in water. A VHEE-enabled research treatment planning system was used to evaluate the plan quality achievable with VHEE beams of different energies, compared to 250 MeV TP beams for a glioblastoma, an oesophagus, and a prostate cancer case. RESULTS Like TP, VHEE above 100 MeV can treat targets with roughly flat (within ± 20 %) depth-dose distributions. The achievable dosimetric target conformity and adjacent organs-at-risk (OAR) sparing is consequently driven for both modalities by their lateral beam penumbrae. Electron beams of 400[500] MeV match the penumbra of 200[250] MeV TP beams and penumbra is increased for lower electron energies. For the investigated patient cases, VHEE plans with energies of 150 MeV and above achieved a dosimetric plan quality comparable to that of 250 MeV TP plans. For the glioblastoma and the oesophagus case, although having a decreased conformity, even 100 MeV VHEE plans provided a similar target coverage and OAR sparing compared to TP. CONCLUSIONS VHEE-based FLASH-RT using sufficiently high beam energies may provide a lighter-particle alternative to TP-based FLASH-RT with comparable dosimetric plan quality.
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Affiliation(s)
- Till Tobias Böhlen
- Institute of Radiation Physics, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - Jean-François Germond
- Institute of Radiation Physics, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - Laurent Desorgher
- Institute of Radiation Physics, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - Izabella Veres
- Institute of Radiation Physics, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | | | | | | | - Fernanda G Herrera
- Department of Radiation Oncology, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - Esat Mahmut Ozsahin
- Department of Radiation Oncology, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - Jean Bourhis
- Department of Radiation Oncology, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - François Bochud
- Institute of Radiation Physics, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - Raphaël Moeckli
- Institute of Radiation Physics, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland.
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2
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Struelens L, Huet C, Broggio D, Dabin J, Desorgher L, Giussani A, Li WB, Nosske D, Lee YK, Cunha L, Carapinha MJR, Medvedec M, Covens P. Joint EURADOS-EANM initiative for an advanced computational framework for the assessment of external dose rates from nuclear medicine patients. EJNMMI Phys 2024; 11:38. [PMID: 38647987 DOI: 10.1186/s40658-024-00638-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Accepted: 03/28/2024] [Indexed: 04/25/2024] Open
Abstract
BACKGROUND In order to ensure adequate radiation protection of critical groups such as staff, caregivers and the general public coming into proximity of nuclear medicine (NM) patients, it is necessary to consider the impact of the radiation emitted by the patients during their stay at the hospital or after leaving the hospital. Current risk assessments are based on ambient dose rate measurements in a single position at a specified distance from the patient and carried out at several time points after administration of the radiopharmaceutical to estimate the whole-body retention. The limitations of such an approach are addressed in this study by developing and validating a more advanced computational dosimetry approach using Monte Carlo (MC) simulations in combination with flexible and realistic computational phantoms and time activity distribution curves from reference biokinetic models. RESULTS Measurements of the ambient dose rate equivalent Ḣ*(10) at 1 m from the NM patient have been successfully compared against MC simulations with 5 different codes using the ICRP adult reference computational voxel phantoms, for typical clinical procedures with 99mTc-HDP/MDP, 18FDG and Na131I. All measurement data fall in the 95% confidence intervals, determined for the average simulated results. Moreover, the different MC codes (MCNP-X, PHITS, GATE, GEANT4, TRIPOLI-4®) have been compared for a more realistic scenario where the effective dose rate Ė of an exposed individual was determined in positions facing and aside the patient model at 30 cm, 50 cm and 100 cm. The variation between codes was lower than 8% for all the radiopharmaceuticals at 1 m, and varied from 5 to 16% for the face-to face and side-by-side configuration at 30 cm and 50 cm. A sensitivity study on the influence of patient model morphology demonstrated that the relative standard deviation of Ḣ*(10) at 1 m for the range of included patient models remained under 16% for time points up to 120 min post administration. CONCLUSIONS The validated computational approach will be further used for the evaluation of effective dose rates per unit administered activity for a variety of close-contact configurations and a range of radiopharmaceuticals as part of risk assessment studies. Together with the choice of appropriate dose constraints this would facilitate the setting of release criteria and patient restrictions.
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Affiliation(s)
- Lara Struelens
- Belgian Nuclear Research Center (SCK CEN), Nuclear Medical Applications, Boeretang 200, 2400, Mol, Belgium.
| | - Christelle Huet
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-SANTE/SDOS, 31 Avenue de La Division Leclerc, 92260, Fontenay-Aux-Roses, France
| | - David Broggio
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-SANTE/SDOS, 31 Avenue de La Division Leclerc, 92260, Fontenay-Aux-Roses, France
| | - Jérémie Dabin
- Belgian Nuclear Research Center (SCK CEN), Nuclear Medical Applications, Boeretang 200, 2400, Mol, Belgium
| | - Laurent Desorgher
- Institute of Radiation Physics, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Augusto Giussani
- Federal Office for Radiation Protection (BfS), Ingolstädter Landstr. 1, 85764, Oberschleißheim, Germany
| | - Wei Bo Li
- Federal Office for Radiation Protection (BfS), Ingolstädter Landstr. 1, 85764, Oberschleißheim, Germany
| | - Dietmar Nosske
- Federal Office for Radiation Protection (BfS), Ingolstädter Landstr. 1, 85764, Oberschleißheim, Germany
| | - Yi-Kang Lee
- Université Paris-Saclay, CEA, Service d'études des réacteurs et de mathématiques appliquées, 91191, Gif-Sur-Yvette, France
| | - Lidia Cunha
- Nuclear Medicine and Molecular Imaging, IsoPor-Azores, Canada do Breado, 9700, Angra Do Heroismo, Azores, Portugal
| | - Maria J R Carapinha
- ESTeSL-Escola Superior de Tecnologia da Saúde, Instituto Politécnico de Lisboa, Lisboa, Portugal
| | - Mario Medvedec
- Department of Nuclear Medicine and Radiation Protection, University Hospital Centre Zagreb, Zagreb, Croatia
| | - Peter Covens
- Molecular Imaging and Therapy, Vrije Universiteit Brussel (VUB), Brussels, Belgium
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3
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Vozenin MC, Alaghband Y, Drayson OGG, Piaget F, Leavitt R, Allen BD, Doan NL, Rostomyan T, Stabilini A, Reggiani D, Hajdas W, Yukihara EG, Norbury JW, Bailat C, Desorgher L, Baulch JE, Limoli CL. More May Not be Better: Enhanced Spacecraft Shielding May Exacerbate Cognitive Decrements by Increasing Pion Exposures during Deep Space Exploration. Radiat Res 2024; 201:93-103. [PMID: 38171489 DOI: 10.1667/rade-23-00241.1.s1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Accepted: 12/15/2023] [Indexed: 01/05/2024]
Abstract
The pervasiveness of deep space radiation remains a confounding factor for the transit of humans through our solar system. Spacecraft shielding both protects astronauts but also contributes to absorbed dose through galactic cosmic ray interactions that produce secondary particles. The resultant biological effects drop to a minimum for aluminum shielding around 20 g/cm2 but increase with additional shielding. The present work evaluates for the first time, the impact of secondary pions on central nervous system functionality. The fractional pion dose emanating from thicker shielded spacecraft regions could contribute up to 10% of the total absorbed radiation dose. New results from the Paul Scherrer Institute have revealed that low dose exposures to 150 MeV positive and negative pions, akin to a Mars mission, result in significant, long-lasting cognitive impairments. These surprising findings emphasize the need to carefully evaluate shielding configurations to optimize safe exposure limits for astronauts during deep space travel.
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Affiliation(s)
- Marie-Catherine Vozenin
- Laboratory of Radiation Oncology, Department of Radiation Oncology, Lausanne University Hospital and University of Lausanne, Switzerland
| | - Yasaman Alaghband
- Department of Radiation Oncology, University of California, Irvine, California 92697-2695
| | - Olivia G G Drayson
- Department of Radiation Oncology, University of California, Irvine, California 92697-2695
| | - Filippo Piaget
- Laboratory of Radiation Oncology, Department of Radiation Oncology, Lausanne University Hospital and University of Lausanne, Switzerland
| | - Ron Leavitt
- Laboratory of Radiation Oncology, Department of Radiation Oncology, Lausanne University Hospital and University of Lausanne, Switzerland
| | - Barrett D Allen
- Department of Radiation Oncology, University of California, Irvine, California 92697-2695
| | - Ngoc-Lien Doan
- Department of Radiation Oncology, University of California, Irvine, California 92697-2695
| | | | | | | | | | | | | | - Claude Bailat
- Institute of Radiation Physics, Lausanne University Hospital and University of Lausanne, Switzerland
| | - Laurent Desorgher
- Institute of Radiation Physics, Lausanne University Hospital and University of Lausanne, Switzerland
| | - Janet E Baulch
- Department of Radiation Oncology, University of California, Irvine, California 92697-2695
| | - Charles L Limoli
- Department of Radiation Oncology, University of California, Irvine, California 92697-2695
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4
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Juget F, Talip Z, Buchillier T, Durán MT, Nedjadi Y, Desorgher L, Bochud F, Grundler P, van der Meulen NP, Bailat C. Corrigendum to "Determination of the gamma and X-ray emission intensities of terbium-161" [Appl. Radiat. Isot. 174 (2021) 109770]. Appl Radiat Isot 2023; 200:110955. [PMID: 37516578 DOI: 10.1016/j.apradiso.2023.110955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/31/2023]
Affiliation(s)
| | - Zeynep Talip
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute, Villigen-PSI, Switzerland
| | | | | | | | | | | | - Pascal Grundler
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute, Villigen-PSI, Switzerland
| | - Nicholas P van der Meulen
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute, Villigen-PSI, Switzerland; Laboratory of Radiochemistry, Paul Scherrer Institute, Villigen-PSI, Switzerland
| | - Claude Bailat
- Institute of Radiation Physics, Lausanne, Switzerland
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Desorgher L, Stabilini A, Rostomyan T, Reggiani D, Hajdas W, Marcinkowski RM, Vozenin MC, Limoli CL, Yukihara EG, Bailat C. Dosimetry of the PIM1 Pion Beam at the Paul Scherrer Institute for Radiobiological Studies of Mice. Radiat Res 2023; 200:357-365. [PMID: 37702413 DOI: 10.1667/rade-23-00029.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Accepted: 07/31/2023] [Indexed: 09/14/2023]
Abstract
Significant past work has identified unexpected risks of central nervous system (CNS) exposure to the space radiation environment, where long-lasting functional decrements have been associated with multiple ion species delivered at low doses and dose rates. As shielding is the only established intervention capable of limiting exposure to the dangerous radiation fields in space, the recent discovery that pions, emanating from regions of enhanced shielding, can contribute significantly to the total absorbed dose on a deep space mission poses additional concerns. As a prerequisite to biological studies evaluating pion dose equivalents for various CNS exposure scenarios of mice, a careful dosimetric validation study is required. Within our ultimate goal of evaluating the functional consequences of defined pion exposures to CNS functionality, we report in this article the detailed dosimetry of the PiMI pion beam line at the Paul Scherrer Institute, which was developed in support of radiobiological experiments. Beam profiles and contamination of the beam by protons, electrons, positrons and muons were characterized prior to the mice irradiations. The dose to the back and top of the mice was measured using thermoluminescent dosimeters (TLD) and optically simulated luminescence (OSL) to cross-validate the dosimetry results. Geant4 Monte Carlo simulations of radiation exposure of a mouse phantom in water by charged pions were also performed to quantify the difference between the absorbed dose from the OSL and TLD and the absorbed dose to water, using a simple model of the mouse brain. The absorbed dose measured by the OSL dosimeters and TLDs agreed within 5-10%. A 30% difference between the measured absorbed dose and the dose calculated by Geant4 in the dosimeters was obtained, probably due to the approximated Monte Carlo configuration compared to the experiment. A difference of 15-20% between the calculated absorbed dose to water at a 5 mm depth and in the passive dosimeters was obtained, suggesting the need for a correction factor of the measured dose to obtain the absorbed dose in the mouse brain. Finally, based on the comparison of the experimental data and the Monte Carlo calculations, we consider the dose measurement to be accurate to within 15-20%.
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Affiliation(s)
- L Desorgher
- Institute of Radiation Physics, Lausanne University Hospital and Lausanne University, Switzerland
| | - A Stabilini
- Paul Scherrer Institute (PSI), Villigen, Switzerland
| | - T Rostomyan
- Paul Scherrer Institute (PSI), Villigen, Switzerland
| | - D Reggiani
- Paul Scherrer Institute (PSI), Villigen, Switzerland
| | - W Hajdas
- Paul Scherrer Institute (PSI), Villigen, Switzerland
| | - R M Marcinkowski
- Paul Scherrer Institute (PSI), Villigen, Switzerland
- SE2S GMBH, Boppelsen ZH, Switzerland
| | - M-C Vozenin
- CHUV-Radiation-oncology Laboratory, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - C L Limoli
- Department of Radiation Oncology, University of California, Irvine, California
| | - E G Yukihara
- Paul Scherrer Institute (PSI), Villigen, Switzerland
| | - C Bailat
- Institute of Radiation Physics, Lausanne University Hospital and Lausanne University, Switzerland
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6
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Nedjadi Y, Juget F, Durán MT, Desorgher L, Bochud F, Bailat C. Activity standardisation of 177Lu. Appl Radiat Isot 2023; 200:110986. [PMID: 37597267 DOI: 10.1016/j.apradiso.2023.110986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 08/08/2023] [Accepted: 08/14/2023] [Indexed: 08/21/2023]
Abstract
177Lu decays through low-energy β-- and γ-emissions in addition to conversion and Auger electrons. To support the use of this radiopharmaceutical in Switzerland, a 177Lu solution was standardised using the β-γ coincidence technique, as well as the TDCR method. The solution had no 177mLu impurity. Primary coincidence measurements, with plastic scintillators for beta detection, were carried out using both analogue and digital electronics. TDCR measurements using only defocusing were also made. Monte Carlo calculations were used to compute the detection efficiency. The coincidence measurements with both analogue and digital electronics are compatible within one standard uncertainty, but they are lower than (and discrepant with) the TDCR measurements. An ampoule of this solution was submitted to the BIPM as a contribution to the Système International de Référence.
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7
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Audouin J, Hofverberg P, Ngono-Ravache Y, Desorgher L, Baldacchino G. Intermediate LET-like effect in distal part of proton Bragg peak revealed by track-ends imaging during super-Fricke radiolysis. Sci Rep 2023; 13:15460. [PMID: 37726376 PMCID: PMC10509149 DOI: 10.1038/s41598-023-42639-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 09/13/2023] [Indexed: 09/21/2023] Open
Abstract
Upstream of the efficiency of proton or carbon ion beams in cancer therapy, and to optimize hadrontherapy results, we analysed the chemistry of Fricke solutions in track-end of 64-MeV protons and 1.14-GeV carbon ions. An original optical setup is designed to determine the primary track-segment yields along the last millimetres of the ion track with a sub-millimetre resolution. The Fe3+-yield falls in the Bragg peak to (4.9 ± 0.4) × 10-7 mol/J and 1.9 × 10-7 mol/J, under protons and carbon ions respectively. Beyond the Bragg peak, a yield recovery is observed over 1 mm for proton beams. It is attributed to the intermediate-LET of protons in this region where their energy decreases and energy distribution becomes broader, in relation with the longitudinal straggling of the beam. Consequently to this LET decrease in the distal part of the Bragg peak, Fe3+-yield increases. For the first time, this signature is highlighted at the chemical level under proton irradiation. Nevertheless, this phenomenon is not identified for carbon ion beams since their straggling is lower. It would need a greater spatial resolution to be observed.
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Affiliation(s)
- J Audouin
- Université Paris-Saclay, CEA, CNRS, LIDYL, 91191, Gif-sur-Yvette, France
| | | | - Y Ngono-Ravache
- CIMAP, CEA-CNRS-ENSICAEN-UNICAEN, Normandy University, Cedex 04, 14050, Caen, France
| | - L Desorgher
- Institute of Radiation Physics (IRA), Lausanne University Hospital and University of Lausanne, CH-1007, Lausanne, Switzerland
| | - G Baldacchino
- Université Paris-Saclay, CEA, CNRS, LIDYL, 91191, Gif-sur-Yvette, France.
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8
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Böhlen TT, Germond JF, Traneus E, Vallet V, Desorgher L, Ozsahin EM, Bochud F, Bourhis J, Moeckli R. 3D-conformal very-high energy electron therapy as candidate modality for FLASH-RT: A treatment planning study for glioblastoma and lung cancer. Med Phys 2023; 50:5745-5756. [PMID: 37427669 DOI: 10.1002/mp.16586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 05/27/2023] [Indexed: 07/11/2023] Open
Abstract
BACKGROUND Pre-clinical ultra-high dose rate (UHDR) electron irradiations on time scales of 100 ms have demonstrated a remarkable sparing of brain and lung tissues while retaining tumor efficacy when compared to conventional dose rate irradiations. While clinically-used gantries and intensity modulation techniques are too slow to match such time scales, novel very-high energy electron (VHEE, 50-250 MeV) radiotherapy (RT) devices using 3D-conformed broad VHEE beams are designed to deliver UHDR treatments that fulfill these timing requirements. PURPOSE To assess the dosimetric plan quality obtained using VHEE-based 3D-conformal RT (3D-CRT) for treatments of glioblastoma and lung cancer patients and compare the resulting treatment plans to those delivered by standard-of-care intensity modulated photon RT (IMRT) techniques. METHODS Seven glioblastoma patients and seven lung cancer patients were planned with VHEE-based 3D-CRT using 3 to 16 coplanar beams with equidistant angular spacing and energies of 100 and 200 MeV using a forward planning approach. Dose distributions, dose-volume histograms, coverage (V95% ) and homogeneity (HI98% ) for the planning target volume (PTV), as well as near-maximum doses (D2% ) and mean doses (Dmean ) for organs-at-risk (OAR) were evaluated and compared to clinical IMRT plans. RESULTS Mean differences of V95% and HI98% of all VHEE plans were within 2% or better of the IMRT reference plans. Glioblastoma plan dose metrics obtained with VHEE configurations of 200 MeV and 3-16 beams were either not significantly different or were significantly improved compared to the clinical IMRT reference plans. All OAR plan dose metrics evaluated for VHEE plans created using 5 beams of 100 MeV were either not significantly different or within 3% on average, except for Dmean for the body, Dmean for the brain, D2% for the brain stem, and D2% for the chiasm, which were significantly increased by 1, 2, 6, and 8 Gy, respectively (however below clinical constraints). Similarly, the dose metrics for lung cancer patients were also either not significantly different or were significantly improved compared to the reference plans for VHEE configurations with 200 MeV and 5 to 16 beams with the exception of D2% and Dmean to the spinal canal (however below clinical constraints). For the lung cancer cases, the VHEE configurations using 100 MeV or only 3 beams resulted in significantly worse dose metrics for some OAR. Differences in dose metrics were, however, strongly patient-specific and similar for some patient cases. CONCLUSIONS VHEE-based 3D-CRT may deliver conformal treatments to simple, mostly convex target shapes in the brain and the thorax with a limited number of critical adjacent OAR using a limited number of beams (as low as 3 to 7). Using such treatment techniques, a dosimetric plan quality comparable to that of standard-of-care IMRT can be achieved. Hence, from a treatment planning perspective, 3D-conformal UHDR VHEE treatments delivered on time scales of 100 ms represent a promising candidate technique for the clinical transfer of the FLASH effect.
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Affiliation(s)
- Till Tobias Böhlen
- Institute of Radiation Physics, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - Jean-François Germond
- Institute of Radiation Physics, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | | | - Veronique Vallet
- Institute of Radiation Physics, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - Laurent Desorgher
- Institute of Radiation Physics, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - Esat Mahmut Ozsahin
- Department of Radiation Oncology, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - François Bochud
- Institute of Radiation Physics, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - Jean Bourhis
- Department of Radiation Oncology, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - Raphaël Moeckli
- Institute of Radiation Physics, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
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9
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Desorgher L, Berthet A, Rossier J, Bochud F, Froidevaux P. Dosimetry in the lungs of α-particles ( 210Po) and β-particles ( 210Pb) present in the tobacco smoke of conventional cigarettes and heated tobacco products. J Environ Radioact 2023; 263:107178. [PMID: 37060833 DOI: 10.1016/j.jenvrad.2023.107178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 03/31/2023] [Accepted: 04/03/2023] [Indexed: 05/06/2023]
Abstract
Tobacco products contain radioactive 210Pb and 210Po which can be transferred from the filler to the mainstream smoke. When inhaled, they can contribute to the radioactive dose to the lungs and are suspected to significantly contribute to lung cancer from smoking. Currently, no data are available on the radioactive risk of the heated tobacco products (HTP). However, due to the relatively high heat involved in some of these devices, there are concerns about the volatility of polonium particles. Here we used data on the 210Po and 210Pb content in tobacco smoke along with biokinetic and dosimetric models to compute the effective dose induced by conventional smoking and by using an HTP device (PMI IQOS system). Results show that conventional smoking of one pack per day induces a dose to the lung of about 0.3 mSv/year. This dose decreases by a factor of ten (0.03 mSv/year) for the IQOS system. However, this dose reduction is not obtained by specific countermeasures but by the fact that the IQOS system heats only 15% of the tobacco filler to the target temperature of 330 °C. When heated homogeneously to 300 °C, both conventional and Heets (IQOS) cigarettes release about 80% of the 210Po from the tobacco, leading to similar doses to lungs.
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Affiliation(s)
- Laurent Desorgher
- Institute of Radiation Physics, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Aurélie Berthet
- University of Lausanne, Ctr Primary Care & Publ Hlth Unisante, Lausanne, Switzerland
| | - Jérémie Rossier
- Institute of Radiation Physics, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - François Bochud
- Institute of Radiation Physics, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Pascal Froidevaux
- Institute of Radiation Physics, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland.
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10
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Chappuis F, Tran HN, Zein SA, Bailat C, Incerti S, Bochud F, Desorgher L. The general-purpose Geant4 Monte Carlo toolkit and its Geant4-DNA extension to investigate mechanisms underlying the FLASH effect in radiotherapy: Current status and challenges. Phys Med 2023; 110:102601. [PMID: 37201453 DOI: 10.1016/j.ejmp.2023.102601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 04/06/2023] [Accepted: 05/01/2023] [Indexed: 05/20/2023] Open
Abstract
FLASH radiotherapy is a promising approach to cancer treatment that offers several advantages over conventional radiotherapy. With this novel technique, high doses of radiation are delivered in a short period of time, inducing the so-called FLASH effect - a phenomenon characterized by healthy tissue sparing without alteration of tumor control. The mechanisms behind the FLASH effect remain unknown. One way to approach this problem is to gain insight into the initial parameters that can distinguish FLASH from conventional irradiation by simulating particle transport in aqueous media using the general-purpose Geant4 Monte Carlo toolkit and its Geant4-DNA extension. This review article discusses the current status of Geant4 and Geant4-DNA simulations to investigate mechanisms underlying the FLASH effect, as well as the challenges faced in this research field. One of the primary challenges is to accurately simulate the experimental irradiation parameters. Another challenge is the temporal extension of the simulations. This review also focuses on two hypotheses to explain the FLASH effect - namely the oxygen depletion hypothesis and the inter-track interactions hypothesis - and discusses how the Geant4 toolkit can be used to investigate them. The aim of this review is to provide an overview of Geant4 and Geant4-DNA simulations for FLASH radiotherapy and to highlight the challenges that need to be overcome in order to better study the FLASH effect.
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Affiliation(s)
- Flore Chappuis
- Institute of Radiation Physics (IRA), Lausanne University Hospital and University of Lausanne, CH-1007 Lausanne, Switzerland
| | - Hoang Ngoc Tran
- Univ. Bordeaux, CNRS, LP2I Bordeaux, UMR 5797, F-33170 Gradignan, France
| | - Sara A Zein
- Univ. Bordeaux, CNRS, LP2I Bordeaux, UMR 5797, F-33170 Gradignan, France
| | - Claude Bailat
- Institute of Radiation Physics (IRA), Lausanne University Hospital and University of Lausanne, CH-1007 Lausanne, Switzerland
| | - Sébastien Incerti
- Univ. Bordeaux, CNRS, LP2I Bordeaux, UMR 5797, F-33170 Gradignan, France
| | - François Bochud
- Institute of Radiation Physics (IRA), Lausanne University Hospital and University of Lausanne, CH-1007 Lausanne, Switzerland
| | - Laurent Desorgher
- Institute of Radiation Physics (IRA), Lausanne University Hospital and University of Lausanne, CH-1007 Lausanne, Switzerland.
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Chappuis F, Grilj V, Tran HN, Zein SA, Bochud F, Bailat C, Incerti S, Desorgher L. Modeling of scavenging systems in water radiolysis with Geant4-DNA. Phys Med 2023; 108:102549. [PMID: 36921424 DOI: 10.1016/j.ejmp.2023.102549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 01/11/2023] [Accepted: 02/13/2023] [Indexed: 03/16/2023] Open
Abstract
PURPOSE This paper presents the capabilities of the Geant4-DNA Monte Carlo toolkit to simulate water radiolysis with scavengers using the step-by-step (SBS) or the independent reaction times (IRT) methods. It features two examples of application areas: (1) computing the escape yield of H2O2 following a 60Co γ-irradiation and (2) computing the oxygen depletion in water irradiated with 1 MeV electrons. METHODS To ease the implementation of the chemical stage in Geant4-DNA, we developed a user interface that helps define the chemical reactions and set the concentration of scavengers. The first application area example required two computational steps to perform water radiolysis using NO2- and NO3- as scavengers and a 60Co irradiation. The oxygen depletion computation technique for the second application area example consisted of simulating track segments of 1 MeV electrons and determining the radio-induced loss and gain of oxygen molecules. RESULTS The production of H2O2 under variable scavenging levels is consistent with the literature; the mean relative difference between the SBS and IRT methods is 7.2 % ± 0.5 %. For the oxygen depletion 1 µs post-irradiation, the mean relative difference between both methods is equal to 9.8 % ± 0.3 %. The results in the microsecond scale depend on the initial partial pressure of oxygen in water. In addition, the computed oxygen depletions agree well with the literature. CONCLUSIONS The Geant4-DNA toolkit makes it possible to simulate water radiolysis in the presence of scavengers. This feature offers perspectives in radiobiology, with the possibility of simulating cell-relevant scavenging mechanisms.
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Affiliation(s)
- Flore Chappuis
- Institute of Radiation Physics (IRA), Lausanne University Hospital and University of Lausanne, CH-1007 Lausanne, Switzerland
| | - Veljko Grilj
- Institute of Radiation Physics (IRA), Lausanne University Hospital and University of Lausanne, CH-1007 Lausanne, Switzerland
| | - Hoang Ngoc Tran
- Univ. Bordeaux, CNRS, LP2I Bordeaux, UMR 5797, F-33170 Gradignan, France
| | - Sara A Zein
- Univ. Bordeaux, CNRS, LP2I Bordeaux, UMR 5797, F-33170 Gradignan, France
| | - François Bochud
- Institute of Radiation Physics (IRA), Lausanne University Hospital and University of Lausanne, CH-1007 Lausanne, Switzerland
| | - Claude Bailat
- Institute of Radiation Physics (IRA), Lausanne University Hospital and University of Lausanne, CH-1007 Lausanne, Switzerland
| | - Sébastien Incerti
- Univ. Bordeaux, CNRS, LP2I Bordeaux, UMR 5797, F-33170 Gradignan, France
| | - Laurent Desorgher
- Institute of Radiation Physics (IRA), Lausanne University Hospital and University of Lausanne, CH-1007 Lausanne, Switzerland.
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Chappuis F, Tran HN, Incerti S, Kacem H, Grilj V, Froidevaux P, Goncalves PJ, Bochud F, Bailat C, Vozenin MC, Desorgher L. FLASH Mechanisms Track (Oral Presentations) MODELLING OF WATER RADIOLYSIS FOR ULTRA-HIGH DOSE RATE (FLASH) ELECTRON BEAMS IN GEANT4-DNA. Phys Med 2022. [DOI: 10.1016/s1120-1797(22)01520-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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13
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Böhlen T, Germond JF, Traneus E, Desorgher L, Vozenin MC, Bourhis J, Bailat C, Bochud F, Moeckli R. FLASH Modalities Track (Oral Presentations) CAN UHDR VHEE DEVICES WITH ONLY A FEW FIXED BEAMS PROVIDE COMPETITIVE TREATMENT PLANS COMPARED TO VMAT? Phys Med 2022. [DOI: 10.1016/s1120-1797(22)01514-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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14
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Desorgher L, Mosimann N, Althaus R, Wirz C, Bailat C, Medici S, Bochud F. Monte Carlo simulations of the whole-body counter at Spiez Laboratory Switzerland: Impact of phantom size and biokinetic model. RADIAT MEAS 2022. [DOI: 10.1016/j.radmeas.2022.106720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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15
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Huet C, Eakins J, Zankl M, Gómez-Ros JM, Jansen J, Moraleda M, Struelens L, Akar DK, Borbinha J, Brkić H, Bui DK, Capello K, Linh Dang TM, Desorgher L, Di Maria S, Epstein L, Faj D, Fantinova K, Ferrari P, Gossio S, Hunt J, Jovanovic Z, Kim HS, Krstic D, Le NT, Lee YK, Murugan M, Nadar MY, Nguyen NQ, Nikezic D, Patni HK, Santos DS, Tremblay M, Trivino S, Tymińska K. Monte Carlo calculation of organ and effective doses due to photon and neutron point sources and typical X-ray examinations: Results of an international intercomparison exercise. RADIAT MEAS 2022. [DOI: 10.1016/j.radmeas.2021.106695] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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16
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Eakins J, Huet C, Brkić H, Capello K, Desorgher L, Epstein L, Hunt J, Kim H, Krstic D, Lee YK, Manohari M, Nikezic D, Shukrun R, Souza-Santos D, Tymińska K. Monte Carlo calculation of organ and effective dose rates from ground contaminated by Am-241: Results of an international intercomparison exercise. RADIAT MEAS 2021. [DOI: 10.1016/j.radmeas.2021.106649] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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17
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Cherbuin N, Ollivier J, Jorge P, Grilj V, Chappuis F, Desorgher L, Bailat C, Bochud F, Jorge Pires J, Vozenin M. PO-1930 Plasmid DNA damages after FLASH vs conventional dose rate irradiations in various oxygen conditions. Radiother Oncol 2021. [DOI: 10.1016/s0167-8140(21)08381-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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18
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Gómez-Ros JM, Moraleda M, Arce P, Bui DK, Dang TML, Desorgher L, Kim HS, Krstic D, Kuć M, Le NT, Lee YK, Nguyen NQ, Nikezic D, Tymińska K, Vrba T. Monte Carlo calculation of the organ equivalent dose and effective dose due to immersion in a 16N beta source in air using the ICRP reference phantoms. RADIAT MEAS 2021. [DOI: 10.1016/j.radmeas.2021.106612] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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19
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Juget F, Talip Z, Buchillier T, Durán MT, Nedjadi Y, Desorgher L, Bochud F, Grundler P, van der Meulen NP, Bailat C. Determination of the gamma and X-ray emission intensities of terbium-161. Appl Radiat Isot 2021; 174:109770. [PMID: 34051529 DOI: 10.1016/j.apradiso.2021.109770] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 04/12/2021] [Accepted: 05/05/2021] [Indexed: 11/26/2022]
Abstract
In this study, the gamma and X-ray emission intensities of 161Tb were determined using a high-purity germanium spectrometer. The samples used were previously standardised by coincidence counting and Triple to Double Coincidence Ratio (TDCR) methods. A total of 28 gamma-rays and 4 X-rays were measured and compared with previous measurements performed more than 30 years ago. Most of the lines are in agreement, while large discrepancies are observed for 5 lines. The uncertainties have been dramatically decreased with respect to previous measurements giving a better knowledge of the 161 Tb day.
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Affiliation(s)
| | - Zeynep Talip
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute, Villigen-PSI, Switzerland
| | | | | | | | | | | | - Pascal Grundler
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute, Villigen-PSI, Switzerland
| | - Nicholas P van der Meulen
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute, Villigen-PSI, Switzerland; Laboratory of Radiochemistry, Paul Scherrer Institute, Villigen-PSI, Switzerland
| | - Claude Bailat
- Institute of Radiation Physics, Lausanne, Switzerland
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20
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Nedjadi Y, Desorgher L, Juget F, Buchillier T, Bochud F, Bailat C. Activity standardisation of 223Ra. Appl Radiat Isot 2021; 174:109788. [PMID: 34051527 DOI: 10.1016/j.apradiso.2021.109788] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 05/17/2021] [Accepted: 05/18/2021] [Indexed: 09/30/2022]
Abstract
We report here on the primary activity standardisation of a223Ra dichloride solution in equilibrium with its decay daughters. Both the triple-to-double-coincidence-ratio (TDCR) method with an in-house TDCR detector and the CIEMAT-NIST efficiency tracing (CNET) technique with a commercial counter were used. The liquid scintillation efficiencies for both methods are about 6 while the activities they predict with about 0.4% relative standard uncertainty agree within 0.15%. For backup, the solution was also standardised with 4πγ NaI(Tl) integral counting with a well-type NaI(Tl) detector, and efficiencies computed by Monte Carlo simulations using the GEANT code. This simple technique, unused previously for this nuclide, yielded an activity concentration compatible with, but 1% lower than, the one determined by liquid scintillation counting.
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21
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Bakr S, Kibédi T, Tee B, Bolst D, Vos M, Alotiby M, Desorgher L, Wright DH, Mantero A, Rosenfeld A, Ivanchenko V, Incerti S, Guatelli S. A benchmarking study of Geant4 for Auger electrons emitted by medical radioisotopes. Appl Radiat Isot 2021; 174:109777. [PMID: 34051528 DOI: 10.1016/j.apradiso.2021.109777] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Revised: 04/11/2021] [Accepted: 05/07/2021] [Indexed: 11/30/2022]
Abstract
Auger emitting radioisotopes are of great interest in targeted radiotherapy because, once internalised in the tumour cells, they can deliver dose locally to the radiation sensitive targets, while not affecting surrounding cells. Geant4 is a Monte Carlo code widely used to characterise the physics mechanism at the basis of targeted radiotherapy. In this work, we benchmarked the modelling of the emission of Auger electrons in Geant4 deriving from the decay of 123I, 124I, 125I radionuclides against existing theoretical approaches. We also compared Geant4 against reference data in the case of 131Cs, which is of interest for brachytherapy. In the case of 125I and 131Cs, the simulation results are compared to experimental measurements as well. Good agreement was found between Geant4 and the reference data. As far as we know, this is the first study aimed to benchmark against experimental measurements the emission of Auger electrons in Geant4 for radiotherapy applications.
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Affiliation(s)
- Samer Bakr
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, Australia.
| | - Tibor Kibédi
- Department of Nuclear Physics, Research School of Physics, The Australian National University, Canberra, Australia
| | - Bryan Tee
- Department of Nuclear Physics, Research School of Physics, The Australian National University, Canberra, Australia
| | - David Bolst
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, Australia
| | - Maarten Vos
- Electronic Materials Engineering, Research School of Physics, The Australian National University, Canberra, Australia
| | - Mohammed Alotiby
- King Abdulaziz City for Science and Technology, Riyadh, Saudi Arabia
| | | | - Dennis Herbert Wright
- International Space Elevator Consortium, California, USA; SLAC National Accelerator Laboratory, California, USA
| | | | - Anatoly Rosenfeld
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, Australia; Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, Australia
| | - Vladimir Ivanchenko
- Geant4 Associates International Ltd., United Kingdom; Tomsk State University, Tomsk, Russia
| | - Sebastien Incerti
- CNRS/IN2P3, Centre d'Etudes Nucléaires de Bordeaux-Gradignan, Bordeaux, France; Université de Bordeaux, Bordeaux, France
| | - Susanna Guatelli
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, Australia; Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, Australia
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22
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Arce P, Bolst D, Bordage MC, Brown JMC, Cirrone P, Cortés-Giraldo MA, Cutajar D, Cuttone G, Desorgher L, Dondero P, Dotti A, Faddegon B, Fedon C, Guatelli S, Incerti S, Ivanchenko V, Konstantinov D, Kyriakou I, Latyshev G, Le A, Mancini-Terracciano C, Maire M, Mantero A, Novak M, Omachi C, Pandola L, Perales A, Perrot Y, Petringa G, Quesada JM, Ramos-Méndez J, Romano F, Rosenfeld AB, Sarmiento LG, Sakata D, Sasaki T, Sechopoulos I, Simpson EC, Toshito T, Wright DH. Report on G4-Med, a Geant4 benchmarking system for medical physics applications developed by the Geant4 Medical Simulation Benchmarking Group. Med Phys 2021; 48:19-56. [PMID: 32392626 PMCID: PMC8054528 DOI: 10.1002/mp.14226] [Citation(s) in RCA: 63] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 04/26/2020] [Accepted: 04/30/2020] [Indexed: 11/05/2022] Open
Abstract
BACKGROUND Geant4 is a Monte Carlo code extensively used in medical physics for a wide range of applications, such as dosimetry, micro- and nanodosimetry, imaging, radiation protection, and nuclear medicine. Geant4 is continuously evolving, so it is crucial to have a system that benchmarks this Monte Carlo code for medical physics against reference data and to perform regression testing. AIMS To respond to these needs, we developed G4-Med, a benchmarking and regression testing system of Geant4 for medical physics. MATERIALS AND METHODS G4-Med currently includes 18 tests. They range from the benchmarking of fundamental physics quantities to the testing of Monte Carlo simulation setups typical of medical physics applications. Both electromagnetic and hadronic physics processes and models within the prebuilt Geant4 physics lists are tested. The tests included in G4-Med are executed on the CERN computing infrastructure via the use of the geant-val web application, developed at CERN for Geant4 testing. The physical observables can be compared to reference data for benchmarking and to results of previous Geant4 versions for regression testing purposes. RESULTS This paper describes the tests included in G4-Med and shows the results derived from the benchmarking of Geant4 10.5 against reference data. DISCUSSION Our results indicate that the Geant4 electromagnetic physics constructor G4EmStandardPhysics_option4 gives a good agreement with the reference data for all the tests. The QGSP_BIC_HP physics list provided an overall adequate description of the physics involved in hadron therapy, including proton and carbon ion therapy. New tests should be included in the next stage of the project to extend the benchmarking to other physical quantities and application scenarios of interest for medical physics. CONCLUSION The results presented and discussed in this paper will aid users in tailoring physics lists to their particular application.
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Affiliation(s)
| | - D Bolst
- Centre For Medical Radiation Physics, University of Wollongong, Wollongong, Australia
| | - M-C Bordage
- CRCT (INSERM and Paul Sabatier University), Toulouse, France
| | - J M C Brown
- Department of Radiation Science and Technology, Delft University of Technology, Delft, The Netherlands
| | | | | | - D Cutajar
- Centre For Medical Radiation Physics, University of Wollongong, Wollongong, Australia
| | | | - L Desorgher
- Institute of Radiation Physics (IRA), Lausanne University Hospital, Lausanne, Switzerland
| | | | - A Dotti
- SLAC National Accelerator Laboratory, Stanford, CA, USA
| | - B Faddegon
- University of California, San Francisco, CA, USA
| | - C Fedon
- Radboud University Medical Center, Nijmegen, The Netherlands
| | - S Guatelli
- Centre For Medical Radiation Physics, University of Wollongong, Wollongong, Australia
| | - S Incerti
- Université de Bordeaux, CNRS/IN2P3, UMR5797, Centre d'Études Nucléaires de Bordeaux Gradignan, Gradignan, France
| | - V Ivanchenko
- Tomsk State University, Tomsk, Russian Federation
- CERN, Geneva, Switzerland
| | - D Konstantinov
- NRC "Kurchatov Institute" - IHEP, Protvino, Russian Federation
| | - I Kyriakou
- Medical Physics Laboratory, University of Ioannina, Ioannina, Greece
| | - G Latyshev
- NRC "Kurchatov Institute" - IHEP, Protvino, Russian Federation
| | - A Le
- Centre For Medical Radiation Physics, University of Wollongong, Wollongong, Australia
| | | | | | | | | | - C Omachi
- Nagoya Proton Therapy Center, Nagoya, Japan
| | | | - A Perales
- Medical Physics Department of Clínica Universidad de Navarra, Pamplona, Spain
| | - Y Perrot
- IRSN, Fontenay-aux-Roses, France
| | | | | | | | - F Romano
- INFN Catania Section, Catania, Italy
- Medical Physics Department, National Physical Laboratory, Teddington, UK
| | - A B Rosenfeld
- Centre For Medical Radiation Physics, University of Wollongong, Wollongong, Australia
| | | | - D Sakata
- Centre For Medical Radiation Physics, University of Wollongong, Wollongong, Australia
| | | | - I Sechopoulos
- Radboud University Medical Center, Nijmegen, The Netherlands
- Dutch Expert Center for Screening (LRCB), Nijmegen, The Netherlands
| | - E C Simpson
- Department of Nuclear Physics, Research School of Physics, Australian National University, Canberra, Australia
| | - T Toshito
- Nagoya Proton Therapy Center, Nagoya, Japan
| | - D H Wright
- SLAC National Accelerator Laboratory, Stanford, CA, USA
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Medici S, Desorgher L, Carbonez P, Damet J, Bochud F, Pitzschke A. Impact of the phantom geometry on the evaluation of the minimum detectable activity following a radionuclide intake: From physical to numerical phantoms. RADIAT MEAS 2020. [DOI: 10.1016/j.radmeas.2020.106485] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Lemesre C, Graf D, Bisch L, Carroz P, Cherbuin N, Damet J, Desorgher L, Siklody CH, Le Bloa M, Pascale P, Pruvot E. Efficiency of the RADPAD Surgical Cap in Reducing Brain Exposure During Pacemaker and Defibrillator Implantation. JACC Clin Electrophysiol 2020; 7:161-170. [PMID: 33602396 DOI: 10.1016/j.jacep.2020.08.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 07/15/2020] [Accepted: 08/03/2020] [Indexed: 11/17/2022]
Abstract
OBJECTIVES This study sought to investigate the RADPAD No Brainer (Worldwide Innovation and Technologies, Overland Park, Kansas) efficiency in reducing brain exposure to scattered radiation. BACKGROUND Cranial radioprotective caps such as the RADPAD No Brainer are being marketed as devices that significantly reduce operator's brain exposure to scattered radiation. However, the efficiency of the RADPAD No Brainer in reducing brain exposure in clinical practice remains unknown to date. METHODS Five electrophysiologists performing device implantations over a 2-month period wore the RADPAD cap with 2 strips of 11 thermoluminescent dosimeter pellets covering the front head above and under the shielded cap. Phantom measurements and Monte Carlo simulations were performed to further investigate brain dose distribution. RESULTS Our study showed that the right half of the operators' front head was the most exposed region during left subpectoral device implantation; the RADPAD cap attenuated the skin front-head exposure but provided no protection to the brain. The exposure of the anterior part of the brain was decreased by a factor of 4.5 compared with the front-head skin value thanks to the skull. The RADPAD cap worn as a protruding horizontal plane, however, reduced brain exposure by a factor of 1.7 (interquartile range: 1.3 to 1.9). CONCLUSIONS During device implantation, the RADPAD No Brainer decreased the skin front head exposure but had no impact on brain dose distribution. The RADPAD No Brainer worn as a horizontal plane worn around the neck reduces brain exposure and confirms that the exposure comes from upward scattered radiation.
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Affiliation(s)
- Camille Lemesre
- Institute for Radiation Physics, University Hospital Centre Vaudois, Lausanne, Switzerland
| | - Denis Graf
- Department of Cardiology, University Hospital Centre Vaudois, Lausanne, Switzerland
| | | | - Patrice Carroz
- Department of Cardiology, University Hospital Centre Vaudois, Lausanne, Switzerland
| | - Nicolas Cherbuin
- Institute for Radiation Physics, University Hospital Centre Vaudois, Lausanne, Switzerland
| | - Jérôme Damet
- Institute for Radiation Physics, University Hospital Centre Vaudois, Lausanne, Switzerland; Department of Radiology, University of Otago, Christchurch, New Zealand
| | - Laurent Desorgher
- Institute for Radiation Physics, University Hospital Centre Vaudois, Lausanne, Switzerland
| | | | - Mathieu Le Bloa
- Department of Cardiology, University Hospital Centre Vaudois, Lausanne, Switzerland
| | - Patrizio Pascale
- Department of Cardiology, University Hospital Centre Vaudois, Lausanne, Switzerland
| | - Etienne Pruvot
- Department of Cardiology, University Hospital Centre Vaudois, Lausanne, Switzerland.
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Nedjadi Y, Juget F, Desorgher L, Durán MT, Bochud F, Müller C, Talip Z, van der Meulen NP, Bailat C. Activity standardisation of 161Tb. Appl Radiat Isot 2020; 166:109411. [PMID: 32961523 DOI: 10.1016/j.apradiso.2020.109411] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 08/18/2020] [Accepted: 09/04/2020] [Indexed: 01/16/2023]
Abstract
161Tb, which emits low-energy β-- and γ-particles in addition to conversion and Auger electrons, has aroused increased interest for medical imaging and therapy. To support the use of this radionuclide, a161Tb solution was standardised using the β-γ coincidence technique, as well as the TDCR method. The solution had 4.5·10-3% of 160Tb impurities. Primary coincidence measurements, with plastic or liquid scintillators for beta detection, were carried out using both analogue and digital electronics. TDCR measurements using defocusing, grey filtering and quenching for varying the efficiency were also made. Monte Carlo calculations were used to compute the detection efficiency. The coincidence measurements with analogue electronics and the TDCR show a good consistency, and are compatible with the digital coincidence results within uncertainties. An ampoule of this solution was submitted to the BIPM as a contribution to the international reference system.
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Affiliation(s)
| | | | | | | | | | - Cristina Müller
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute, Villigen-PSI, Switzerland
| | - Zeynep Talip
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute, Villigen-PSI, Switzerland
| | - Nicholas P van der Meulen
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute, Villigen-PSI, Switzerland; Laboratory of Radiochemistry, Paul Scherrer Institute, Villigen-PSI, Switzerland
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Medici S, Desorgher L, Carbonez P, Damet J, Bochud F, Pitzschke A. In vivo screening measurements with common radiation protection instruments. BIO Web Conf 2019. [DOI: 10.1051/bioconf/20191403003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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27
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Desorgher L, Bochud F, Flury T, Murith C, Baechler S, Bailat C. Model of ambient dose equivalent for radium contamination: Dependence on the geometry of the source. J Environ Radioact 2018; 192:698-708. [PMID: 29674154 DOI: 10.1016/j.jenvrad.2017.12.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 10/31/2017] [Accepted: 12/19/2017] [Indexed: 06/08/2023]
Abstract
Industrial activities involving radium sources, such as watchmaking, were still common up until the 1960s. They produced contaminations in building materials and the soil in a large variety of geometries. The potential remediation of such places requires instruments that are properly calibrated as well as adequate procedures. We have developed a model that estimates the rate of ambient dose equivalent H˙∗(10) at 10 cm and 1 m from a source of 226Ra and its progeny in both the soil or the building materials. Our model, described here, uses Monte Carlo (GEANT4) computed yield functions of H˙∗(10) per unit activity induced by point-like sources in different contaminated materials. Fit functions of the yield curve of H˙∗(10) are provided for outdoor contamination. The model can be used for any geometrical activity distribution and we present an example showing the dependency of H˙∗(10) on the diameter and the depth profile of the sources, for both outdoor and indoor contamination.
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Affiliation(s)
- Laurent Desorgher
- Institute of Radiation Physics (IRA), Lausanne University Hospital, Lausanne, Switzerland.
| | - François Bochud
- Institute of Radiation Physics (IRA), Lausanne University Hospital, Lausanne, Switzerland
| | - Thomas Flury
- Swiss Federal Office of Public Health, Switzerland
| | | | | | - Claude Bailat
- Institute of Radiation Physics (IRA), Lausanne University Hospital, Lausanne, Switzerland
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Bailat CJ, Laedermann JP, Baechler S, Desorgher L, Aroua A, Bochud FO. Dose assessment following an overexposure of a worker at a Swiss nuclear power plant. J Radiol Prot 2017; 37:812-825. [PMID: 28748829 DOI: 10.1088/1361-6498/aa8273] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
AIM The aim of this work was to assess the doses received by a diver exposed to a radiation source during maintenance work in the fuel transfer pool at a Swiss nuclear power plant, and to define whether the statutory limit was breached or not. METHOD Onsite measurements were carried out and different scenarios were simulated using the MicroShield Software and the MCNPX Monte Carlo radiation transport code to estimate the activity of the irradiating object as well as the doses to the limbs and the effective dose delivered to the operator. RESULTS The activity of the object was estimated to 1.8 TBq. From the various dose estimations, a conservative value of 7.5 Sv was proposed for the equivalent dose to the skin on the hands and an effective dose of 28 mSv. CONCLUSION The use of different experimental and calculation methods allowed us to accurately estimate the activity of the object and the dose delivered to the diver, useful information for making a decision on the most appropriate scheme of follow up for the patient.
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Tulej M, Meyer S, Lüthi M, Lasi D, Galli A, Desorgher L, Hajdas W, Karlsson S, Kalla L, Wurz P. Detection efficiency of microchannel plates for e(-) and π(-) in the momentum range from 17.5 to 345 MeV/c. Rev Sci Instrum 2015; 86:083310. [PMID: 26329184 DOI: 10.1063/1.4928063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
High-energy e(-) and π(-) were measured by the multichannel plate (MCP) detector at the PiM1 beam line of the High Intensity Proton Accelerator Facilities located at the Paul Scherrer Institute, Villigen, Switzerland. The measurements provide the absolute detection efficiencies for these particles: 5.8% ± 0.5% for electrons in the beam momenta range 17.5-300 MeV/c and 6.0% ± 1.3% for pions in the beam momenta range 172-345 MeV/c. The pulse height distribution determined from the measurements is close to an exponential function with negative exponent, indicating that the particles penetrated the MCP material before producing the signal somewhere inside the channel. Low charge extraction and nominal gains of the MCP detector observed in this study are consistent with the proposed mechanism of the signal formation by penetrating radiation. A very similar MCP ion detector will be used in the Neutral Ion Mass (NIM) spectrometer designed for the JUICE mission of European Space Agency (ESA) to the Jupiter system, to perform measurements of the chemical composition of the Galilean moon exospheres. The detection efficiency for penetrating radiation determined in the present studies is important for the optimisation of the radiation shielding of the NIM detector against the high-rate and high-energy electrons trapped in Jupiter's magnetic field. Furthermore, the current studies indicate that MCP detectors can be useful to measure high-energy particle beams at high temporal resolution.
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Affiliation(s)
- M Tulej
- Space Research and Planetary Sciences, Physics Institute, University of Bern, CH-3012 Bern, Switzerland
| | - S Meyer
- Space Research and Planetary Sciences, Physics Institute, University of Bern, CH-3012 Bern, Switzerland
| | - M Lüthi
- Space Research and Planetary Sciences, Physics Institute, University of Bern, CH-3012 Bern, Switzerland
| | - D Lasi
- Space Research and Planetary Sciences, Physics Institute, University of Bern, CH-3012 Bern, Switzerland
| | - A Galli
- Space Research and Planetary Sciences, Physics Institute, University of Bern, CH-3012 Bern, Switzerland
| | - L Desorgher
- Laboratory of Particle Physics, Paul Scherrer Institute, CH-5232 Villigen, Switzerland
| | - W Hajdas
- Laboratory of Particle Physics, Paul Scherrer Institute, CH-5232 Villigen, Switzerland
| | - S Karlsson
- Swedish Institute of Space Physics, Space Kampus 1, Kiruna, Sweden
| | - L Kalla
- Swedish Institute of Space Physics, Space Kampus 1, Kiruna, Sweden
| | - P Wurz
- Space Research and Planetary Sciences, Physics Institute, University of Bern, CH-3012 Bern, Switzerland
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Bottollier-Depois JF, Beck P, Bennett B, Bennett L, Bütikofer R, Clairand I, Desorgher L, Dyer C, Felsberger E, Flückiger E, Hands A, Kindl P, Latocha M, Lewis B, Leuthold G, Maczka T, Mares V, McCall MJ, O'Brien K, Rollet S, Rühm W, Wissmann F. Comparison of codes assessing galactic cosmic radiation exposure of aircraft crew. Radiat Prot Dosimetry 2009; 136:317-323. [PMID: 19703832 DOI: 10.1093/rpd/ncp159] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The assessment of the exposure to cosmic radiation onboard aircraft is one of the preoccupations of bodies responsible for radiation protection. Cosmic particle flux is significantly higher onboard aircraft than at ground level and its intensity depends on the solar activity. The dose is usually estimated using codes validated by the experimental data. In this paper, a comparison of various codes is presented, some of them are used routinely, to assess the dose received by the aircraft crew caused by the galactic cosmic radiation. Results are provided for periods close to solar maximum and minimum and for selected flights covering major commercial routes in the world. The overall agreement between the codes, particularly for those routinely used for aircraft crew dosimetry, was better than +/-20 % from the median in all but two cases. The agreement within the codes is considered to be fully satisfactory for radiation protection purposes.
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Affiliation(s)
- J F Bottollier-Depois
- Institute for Radiological Protection and Nuclear Safety, F-92262 Fontenay-aux-Roses, France.
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Le Postollec A, Incerti S, Dobrijevic M, Desorgher L, Santin G, Moretto P, Vandenabeele-Trambouze O, Coussot G, Dartnell L, Nieminen P. Monte Carlo simulation of the radiation environment encountered by a biochip during a space mission to Mars. Astrobiology 2009; 9:311-323. [PMID: 19368517 DOI: 10.1089/ast.2008.0255] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Simulations with a Monte Carlo tool kit have been performed to determine the radiation environment a specific device, called a biochip, would face if it were placed into a rover bound to explore Mars' surface. A biochip is a miniaturized device that can be used to detect organic molecules in situ. Its specific detection part is constituted of proteins whose behavior under cosmic radiation is completely unknown and must be investigated to ensure a good functioning of the device under space conditions. The aim of this study is to define particle species and energy ranges that could be relevant to investigate during experiments on irradiation beam facilities. Several primary particles have been considered for galactic cosmic ray (GCR) and solar energetic particle (SEP) contributions. Ionizing doses accumulated in the biochip and differential fluxes of protons, alphas, neutrons, gammas, and electrons have been established for both the Earth-Mars transit and the journey at Mars' surface. Neutrons and gammas appear as dominant species on martian soil, whereas protons dominate during the interplanetary travel. Depending on solar event occurrence during the mission, an ionizing dose of around a few Grays (1 Gy = 100 rad) is expected.
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Affiliation(s)
- A Le Postollec
- Laboratoire d'Astrophysique de Bordeaux (LAB), Université Bordeaux 1, Floirac, France.
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Bütikofer R, Flückiger EO, Desorgher L, Moser MR. The extreme solar cosmic ray particle event on 20 January 2005 and its influence on the radiation dose rate at aircraft altitude. Sci Total Environ 2008; 391:177-183. [PMID: 18031791 DOI: 10.1016/j.scitotenv.2007.10.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
In January 2005 toward the end of solar activity cycle 23 the Sun was very active. Between 15 and 20 January 2005, the solar active region NOAA AR 10720 produced five powerful solar flares. In association with this major solar activity several pronounced variations in the ground-level cosmic ray intensity were observed. The fifth of these flares (X7.1) produced energetic solar cosmic rays that caused a giant increase in the count rates of the ground-based cosmic ray detectors (neutron monitors). At southern polar neutron monitor stations the increase of the count rate reached several thousand percent. From the recordings of the worldwide network of neutron monitors, we determined the characteristics of the solar particle flux near Earth. In the initial phase of the event, the solar cosmic ray flux near Earth was extremely anisotropic. The energy spectrum of the solar cosmic rays was fairly soft during the main and the decay phase. We investigated also the flux of different secondary particle species in the atmosphere and the radiation dosage at flight altitude. Our analysis shows a maximum increment of the effective dose rate due to solar cosmic rays in the south polar region around 70 degrees S and 130 degrees E at flight altitude of almost three orders of magnitude.
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Affiliation(s)
- R Bütikofer
- Physikalisches Institut, Universität Bern, Sidlerstrasse 5, CH-3012 Bern, Switzerland.
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Desorgher L, Bühler P, Zehnder A, Flückiger EO. Simulation of the outer radiation belt electron flux decrease during the March 26, 1995, magnetic storm. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/2000ja900060] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Abstract
Measurements of the South Atlantic Anomaly (SAA) made with the Radiation Environment Monitor (REM) aboard Mir from November 1994 to February 1996 are presented. During this period an increase of the SAA radiation by approximately 25% is observed, which coincides with a lowering of the radio solar flux. Radio solar flux is one of the parameters controlling the earth's atmospheric distribution and with it the absorption of inner radiation belt protons forming the SAA. Due to the altitude gradient of the atmospheric density, the proton fluxes in the SAA are anisotropic (loss cone, east-west effect). The measured distribution can be accounted for by basic models.
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Affiliation(s)
- P Buhler
- Paul Scherrer Institute, Villigen, Switzerland
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Baye D, Desorgher L, Guillain D, Herschkowitz D. Double-folding interaction for 6He + alpha scattering. Phys Rev C Nucl Phys 1996; 54:2563-2569. [PMID: 9971613 DOI: 10.1103/physrevc.54.2563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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36
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Abstract
Recent measurements of the high-energy charged particle environment with the Radiation Environment Monitor (REM) aboard the Russian Mir space station are presented. Ionizing dose rates in a silicon detector have been measured with two shieldings. The dose is mainly accumulated in two distinct areas, the South Atlantic Anomaly (SAA) and the region of closest approach to the magnetic poles. Whereas the radiation in the South Atlantic Anomaly varied little during 1995, large changes of the daily absorbed doses in the polar regions are observed. A comparison of REM doses with the NASA AP-8 and AE-8 radiation models revealed major differences. AP-8 tends to underestimate the average REM doses, whereas AE-8 overestimates REM doses, and rather describes the worst case.
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Affiliation(s)
- P Buhler
- Paul Scherrer Institute, Villigen, Switzerland
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