Article
Radiology, Nuclear Medicine & Medical Imaging
E. Simiele, N. Viscariello, L. DeWerd
Summary: Using Monte Carlo methods, the study investigated the impact of strong magnetic fields on the stem-effect in plastic scintillation detectors. The results showed no significant change in Cerenkov emission per dose in water for magnetic field strengths up to 1.5 T. Optimizing the light guide optical properties reduced the impact of the magnetic field on CLR, suggesting the use of light guides with low fiber fluorescence for dosimetry measurements in magnetic fields.
Article
Radiology, Nuclear Medicine & Medical Imaging
Carlotta Trigila, Eshani Moghe, Emilie Roncali
Summary: The development of a standalone application to generate crystal reflectance look-up tables for optical Monte Carlo simulations allows for accurate simulation of light transport in scintillators and light collection by photodetectors, aiding in the improvement of radiation detector performance optimization. The application can be easily downloaded, installed, and used, with future optimizations planned to expand the database, reduce computational time through greater parallelization, and include the generation of look-up tables for studying Cerenkov photons transport.
Article
Oncology
Thomas Tessonnier, Stewart Mein, Dietrich W. M. Walsh, Nora Schuhmacher, Hans Liew, Rainer Cee, Michael Galonska, Stefan Scheloske, Christian Schomers, Uli Weber, Stephan Brons, Jurgen Debus, Thomas Haberer, Amir Abdollahi, Andrea Mairani, Ivana Dokic
Summary: The study aimed to investigate the effects of dose, LET, and O-2 concentration on biologic response to ultrahigh dose rate helium ion beams. Results showed no significant differences in cellular response between ultrahigh dose rate and standard dose rate irradiation at different doses and oxygen levels, but a FLASH sparing effect was observed under specific conditions.
INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY BIOLOGY PHYSICS
(2021)
Article
Multidisciplinary Sciences
Emily Cloutier, Luc Beaulieu, Louis Archambault
Summary: Cherenkov emission (CE) is visible light emitted in water mediums during radiotherapy treatment. Polarization imaging is proposed as a method for precise 2D dose measurements using CE. Results show that polarization-corrected CE has good agreement with radiochromic film measurements, indicating improved dose measurements.
SCIENTIFIC REPORTS
(2022)
Article
Multidisciplinary Sciences
Jan Kessler, Francesco Calcavecchia, Thomas D. Kuehne
Summary: Inspired by the universal approximation theorem and the widespread adoption of artificial neural network techniques, feed-forward neural networks are proposed as a general purpose trial wave function for quantum Monte Carlo simulations of continuous many-body systems. The accuracy of the trial wave functions was demonstrated by studying an exactly solvable model system of two trapped interacting particles and the hydrogen dimer. The whole many-body wave function can be represented by a neural network for simple model systems, while the antisymmetry condition of non-trivial fermionic systems is incorporated by means of a Slater determinant.
ADVANCED THEORY AND SIMULATIONS
(2021)
Article
Instruments & Instrumentation
Craig A. Kruschwitz, Ming Wu, Ken Moy
Summary: Monte Carlo simulations were used to study the response of microchannel plates to X-rays, showing changing sensitivity of MCP with angle and decreasing gain sensitivity with increasing X-ray energy. The simulations also indicated that spatial resolution shows little dependence on X-ray energy, but degrades as the angle of incidence relative to the surface normal increases.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2021)
Article
Oncology
Mari Partanen, Jarkko Niemela, Jarkko Ojala, Jani Keyrilainen, Mika Kapanen
Summary: The study investigated the properties of the Nano chamber for small-field dosimetry using measurements and MC simulations. Results showed that the Nano chamber is suitable for small field profile measurements down to 2 x 2 cm(2) and appropriate for PDD measurements. Correction factors and field output factors determined for the Nano chamber in TrueBeam fields demonstrated good accuracy and consistency.
Review
Chemistry, Physical
A. Khodaei, A. N. Z. Rashed, F. Moradi, H. A. Abdul-Rashid, D. A. Bradley
Summary: Geant4 is a versatile simulation platform capable of simulating transport of ionizing radiation and optical photons. It has been widely used in various applications and characterization of radioluminescence radiation detectors. However, compared to the attention given to ionizing radiation transport modeling, there has been less focus on the optimization of optical device components using Geant4.
RADIATION PHYSICS AND CHEMISTRY
(2023)
Article
Mechanics
Lukas Herron, Purushottam Dixit
Summary: The study reveals significant deviations from canonical behavior for small systems near or below the critical point, indicating that the traditional canonical ensemble may not accurately describe small systems. Moreover, the agreement with the canonical ensemble is found to be driven by the decoupling between the system and its surrounding rather than the system size. Additionally, a superstatistical framework allowing for temperature variations of the small magnet shows higher accuracy in capturing its statistics compared to the Gibbs-Boltzmann distribution.
JOURNAL OF STATISTICAL MECHANICS-THEORY AND EXPERIMENT
(2021)
Article
Computer Science, Interdisciplinary Applications
Mathias Lukas, Anne Kluge, Nicola Beindorff, Winfried Brenner
Summary: Recent advances in clinical SPECT instrumentation enable improvements in non-standard multi-isotope experiments at the edge of physical feasibility, enhancing the efficiency of pharmaceutical research. The development of a Monte Carlo simulation model allows for high-accuracy energy spectra, planar images, and tomographic reconstructions for multi-isotope experiments.
IEEE TRANSACTIONS ON MEDICAL IMAGING
(2021)
Article
Engineering, Biomedical
Anna Bianchi, Anna Selva, Brigitte Reniers, Filip Vanhavere, Valeria Conte
Summary: The objective of this study is to compare microdosimetric spectra obtained from experimental measurements and the microdosimetric extension of TOPAS in the same radiation field. The experimental measurements were performed using a miniaturized Tissue equivalent proportional counter, while TOPAS simulations were conducted using Monte Carlo methods. The results show that the shape and average values of the spectra obtained from both methods are consistent, and the average values can predict the increase in radiation quality with depth.
PHYSICS IN MEDICINE AND BIOLOGY
(2023)
Article
Radiology, Nuclear Medicine & Medical Imaging
Michael A. Hupman, Ian G. Hill, Alasdair Syme
Summary: A 1D stemless plastic scintillation detector (SPSD) array was fabricated and used for measuring small field profiles and output factors. The results showed that the segmented scintillator had good agreement with film for all three field sizes and had consistent output factors compared to an ion chamber. In comparison to other bulk scintillators, the segmented scintillator had reduced signal due to lower cross-talk interference.
Article
Engineering, Biomedical
Elena Timakova, Magdalena Bazalova-Carter, Sergei Zavgorodni
Summary: This study evaluated the clinically relevant small field dosimetric properties of a plastic scintillator detector (PSD) with a length and diameter of 1mm and an effective volume of 0.8 mm³. The results showed that the dosimetry system, combined with a scintillation dosimetry system and analysis software, demonstrated good short-term repeatability, dose linearity, and independence of dose rate and angle of irradiation, making it suitable for relative dosimetry measurements for field sizes as small as 0.5 x 0.5 cm².
PHYSICS IN MEDICINE AND BIOLOGY
(2023)
Article
Instruments & Instrumentation
Nicola Mori
Summary: The Generic Geant4 Simulation (GGS) package is designed to accelerate the implementation and deployment of Monte Carlo simulation software based on Geant4 for small- and medium-sized high-energy experiments. It simplifies the task of setting up a full-featured detector simulation by providing generic and reusable implementations of mandatory Geant4 user classes. Additionally, it offers extensibility through a simple plugin system, allowing users to replace the generic implementations with custom ones.
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
(2021)
Article
Engineering, Biomedical
Jinghui Wang, Lei Wang, Peter G. Maxim, Billy W. Loo
Summary: An automated optimization strategy was developed for collimator design in small-field radiotherapy systems. Results showed good agreement with the CyberKnife system when prioritizing minimum penumbra, indicating the potential application of this strategy to more complex collimator designs.
PHYSICS IN MEDICINE AND BIOLOGY
(2021)
Article
Radiology, Nuclear Medicine & Medical Imaging
Haydee M. Linares Rosales, Patricia Duguay-Drouin, Louis Archambault, Sam Beddar, Luc Beaulieu
Article
Oncology
Awalpreet S. Chadha, Jillian R. Gunther, Cheng-En Hsieh, Maureen Aliru, Lakshmi S. Mahadevan, Bhanu P. Venkatesulu, Christopher H. Crane, Prajnan Das, Joseph M. Herman, Eugene J. Koay, Cullen Taniguchi, Emma B. Holliday, Bruce D. Minsky, Yelin Suh, Peter Park, Gabriel Sawakuchi, Sam Beddar, Bruno C. Odisio, Sanjay Gupta, Evelyne Loyer, Harmeet Kaur, Kanwal Raghav, Milind M. Javle, Ahmed O. Kaseb, Sunil Krishnan
RADIOTHERAPY AND ONCOLOGY
(2019)
Article
Instruments & Instrumentation
Fahed Alsanea, Chinmay Darne, Yoshifumi Hojo, Sam Beddar
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
(2019)
Article
Engineering, Biomedical
Gustavo Kertzscher, Sam Beddar
PHYSICS IN MEDICINE AND BIOLOGY
(2019)
Article
Engineering, Biomedical
Fahed Alsanea, Chinmay Darne, Daniel Robertson, Sam Beddar
PHYSICS IN MEDICINE AND BIOLOGY
(2020)
Article
Engineering, Biomedical
Paul Maggi, Steve Peterson, Rajesh Panthi, Dennis Mackin, Hao Yang, Zhong He, Sam Beddar, Jerimy Polf
PHYSICS IN MEDICINE AND BIOLOGY
(2020)
Article
Engineering, Biomedical
Irwin Tendler, Daniel Robertson, Chinmay Darne, Rajesh Panthi, Fahed Alsanea, Charles-Antoine Collins-Fekete, Sam Beddar
Summary: The study compared the image quality of an integrating proton radiography system using different reconstruction techniques, finding that single-event reconstruction had the highest spatial resolution and particle tracking method had the best contrast levels. The results indicate that the image quality of the integrating proton radiography system is promising for potential clinical applications.
PHYSICS IN MEDICINE AND BIOLOGY
(2021)
Article
Radiology, Nuclear Medicine & Medical Imaging
Jerimy C. Polf, Paul Maggi, Rajesh Panthi, Stephen Peterson, Dennis Mackin, Sam Beddar
Summary: The purpose of this study was to investigate how the characteristics of the data acquisition electronics of a Compton camera affect the quality of the recorded prompt gamma interaction data and reconstructed images during clinical proton beam delivery. The study used a simulation model to analyze the changes in recorded data as the number of data readout channels and the readout/reset timing were altered. The findings showed that increasing the number of readout channels and reducing the readout/reset timing resulted in a decrease in the number of recorded events and an improvement in data quality, allowing for higher quality image reconstruction even at high clinical dose rates.
IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES
(2022)
Article
Chemistry, Analytical
Sara Thrower, Surendra Prajapati, Shannon Holmes, Emil Schuler, Sam Beddar
Summary: This study investigates the performance of the W2 scintillator compared to ion chambers for small field dosimetry. The results show excellent agreement between the two detectors in terms of beam profiles and percent depth dose curves. It is also demonstrated that the ion recombination effect of ion chambers can be adequately corrected using the two-voltage method.
Article
Radiology, Nuclear Medicine & Medical Imaging
Rajesh Panthi, Paul Maggi, Stephen Peterson, Dennis Mackin, Jerimy Polf, Sam Beddar
Summary: This study used Geant4 software to simulate the interactions of secondary particles in a Compton camera during the delivery of clinical proton beams. The results showed that for a 150-MeV proton beam, the majority of secondary particles reaching the camera modules were gamma rays, neutrons, and electrons, with a high percentage interacting with the modules. Strategies for reducing neutron backgrounds and non-PG radiation are needed for proton range verification using CCs.
IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES
(2021)
Article
Engineering, Biomedical
Francois Therriault-Proulx, Ramiro Pino, James N. Yang, A. Sam Beddar
PHYSICS IN MEDICINE AND BIOLOGY
(2019)
Article
Radiology, Nuclear Medicine & Medical Imaging
Chinmay D. Darne, Fahed Alsanea, Daniel G. Robertson, Fada Guan, Tinsu Pan, David Grosshans, Sam Beddar
BIOMEDICAL PHYSICS & ENGINEERING EXPRESS
(2019)
Article
Oncology
Lauren E. Colbert, Neal Rebueno, Shalini Moningi, Sam Beddar, Gabriel O. Sawakuchi, Joseph M. Herman, Albert C. Koong, Prajnan Das, Emma B. Holliday, Eugene J. Koay, Cullen M. Taniguchi
ADVANCES IN RADIATION ONCOLOGY
(2018)
Article
Engineering, Biomedical
Yue Yan, Jinzhong Yang, Sam Beddar, Geoffrey Ibbott, Zhifei Wen, Laurence E. Court, Ken-Pin Hwang, Mo Kadbi, Sunil Krishnan, Clifton D. Fuller, Steven J. Frank, James Yang, Peter Balter, Rajat J. Kudchadker, Jihong Wang
PHYSICS IN MEDICINE AND BIOLOGY
(2018)
Article
Engineering, Biomedical
E. Draeger, D. Mackin, S. Peterson, H. Chen, S. Avery, S. Beddar, J. C. Polf
PHYSICS IN MEDICINE AND BIOLOGY
(2018)