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Investigating Variable Rbe In A 12c Minibeam Field With Microdosimetry And Geant4, Emily Debrot, David Bolst, Benjamin James, Linh Tran, Susanna Guatelli, Marco Petasecca, Dale A. Prokopovich, Mark I. Reinhard, Naruhiro Matsufuji, Michael A. Jackson, Michael L. F Lerch, Anatoly B. Rosenfeld

Faculty of Engineering and Information Sciences - Papers: Part B

An experimental and simulation-based study was performed on a 12C ion minibeam radiation therapy (MBRT) field produced with a clinical broad beam and a brass multi-slit collimator (MSC). Silicon-on-insulator (SOI) microdosimeters developed at the Centre for Medical Radiation Physics (CMRP) with micron sized sensitive volumes were used to measure the microdosimetric spectra at varying positions throughout the MBRT field and the corresponding dose-mean lineal energies and RBE for 10% cell survival (RBE10) were calculated using the modified Microdosimetric Kinetic Model (MKM). An increase in the average RBE10 of ∼30% and 10% was observed in the plateau region compared to broad …

Investigation Of Track Structure And Condensed History Physics Models For Applications In Radiation Dosimetry On A Micro And Nano Scale In Geant4, Peter Lazarakis, Sebastien Incerti, Vladimir N. Ivanchenko, Ioanna Kyriakou, Dimitris Emfietzoglou, Stephanie Corde, Anatoly B. Rosenfeld, Michael L. F Lerch, Moeava Tehei, Susanna Guatelli

Faculty of Engineering and Information Sciences - Papers: Part B

Monte Carlo methods apply various physical models, either condensed history (CH) or track structure (TS), to simulate the passage of radiation through matter. Both CH and TS models continue to be applied to radiation dosimetry investigations on a micro and nano scale. However, as there has been no systematic comparison of the use of these models for such applications there can be no quantification of the uncertainty that is being introduced by the choice of physics model. A comparison of CH and TS models available in Geant4, along with a quantification of the differences in calculated quantities on a micro …

Organ Doses From Hepatic Radioembolization With 90y, 153sm, 166ho And 177lu: A Monte Carlo Simulation Study Using Geant4, N A A Hashikin, C H Y Yeong, Susanna Guatelli, B J J Abdullah, K H. Ng, Alessandra Malaroda, Anatoly B. Rosenfeld, A C. Perkins

Faculty of Engineering and Information Sciences - Papers: Part A

90Y-radioembolization is a palliative treatment for liver cancer. 90Y decays via beta emission, making imaging difficult due to absence of gamma radiation. Since post-procedure imaging is crucial, several theranostic radionuclides have been explored as alternatives. However, exposures to gamma radiation throughout the treatment caused concern for the organs near the liver. Geant4 Monte Carlo simulation using MIRD Pamphlet 5 reference phantom was carried out. A spherical tumour with 4.3cm radius was modelled within the liver. 1.82GBq of 90Y sources were isotropically distributed within the tumour, with no extrahepatic shunting. The simulation was repeated with 153Sm, 166Ho and 177Lu. The estimated …

An Implementation Of Discrete Electron Transport Models For Gold In The Geant4 Simulation Toolkit, D Sakata, Sebastien Incerti, M Bordage, N Lampe, Susumu Okada, Dimitris Emfietzoglou, Ioanna Kyriakou, K Murakami, Takashi Sasaki, H Tran, Susanna Guatelli, V Ivantchenko

Faculty of Engineering and Information Sciences - Papers: Part A

Gold nanoparticle (GNP) boosted radiation therapy can enhance the biological effectiveness of radiation treatments by increasing the quantity of direct and indirect radiation-induced cellular damage. As the physical effects of GNP boosted radiotherapy occur across energy scales that descend down to 10 eV, Monte Carlo simulations require discrete physics models down to these very low energies in order to avoid underestimating the absorbed dose and secondary particle generation. Discrete physics models for electron transportation down to 10 eV have been implemented within the Geant4-DNA low energy extension of Geant4. Such models allow the investigation of GNP effects at the nanoscale. …

Progress In Geant4 Electromagnetic Physics Modelling And Validation, J Apostolakis, M Asai, A Bagulya, Jeremy M. C Brown, H Burkhardt, N Chikuma, M A. Cortes-Giraldo, S Elles, V Grichine, Susanna Guatelli, Sebastian Incerti, V N. Ivanchenko, J Jacquemier, O Kadri, M Maire, L Pandola, D Sawkey, T Toshito, L Urban, T T Yamashita

Faculty of Engineering and Information Sciences - Papers: Part A

In this work we report on recent improvements in the electromagnetic (EM) physics models of Geant4 and new validations of EM physics. Improvements have been made in models of the photoelectric effect, Compton scattering, gamma conversion to electron and muon pairs, fluctuations of energy loss, multiple scattering, synchrotron radiation, and high energy positron annihilation. The results of these developments are included in the new Geant4 version 10.1 and in patches to previous versions 9.6 and 10.0 that are planned to be used for production for run-2 at LHC. The Geant4 validation suite for EM physics has been extended and new …

Benchmarking And Validation Of A Geant4-Shadow Monte Carlo Simulation For Dose Calculations In Microbeam Radiation Therapy, Iwan Cornelius, Susanna Guatelli, Pauline Fournier, Jeffrey C. Crosbie, Manuel Sanchez Del Rio, Elke Brauer-Krisch, Anatoly Rosenfeld, Michael Lf Lerch

Faculty of Engineering and Information Sciences - Papers: Part A

Microbeam radiation therapy (MRT) is a synchrotron-based radiotherapy modality that uses high-intensity beams of spatially fractionated radiation to treat tumours. The rapid evolution of MRT towards clinical trials demands accurate treatment planning systems (TPS), as well as independent tools for the verification of TPS calculated dose distributions in order to ensure patient safety and treatment efficacy. Monte Carlo computer simulation represents the most accurate method of dose calculation in patient geometries and is best suited for the purpose of TPS verification. A Monte Carlo model of the ID17 biomedical beamline at the European Synchrotron Radiation Facility has been developed, including …

Comparison Of Nanodosimetric Parameters Of Track Structure Calculated By The Monte Carlo Codes Geant4-Dna And Ptra, P Lazarakis, M U. Bug, E Gargioni, S Guatelli, H Rabus, Anatoly B. Rosenfeld

Faculty of Engineering - Papers (Archive)

The concept of nanodosimetry is based on the assumption that initial damage to cells is related to the number of ionizations (the ionization cluster size) directly produced by single particles within, or in the close vicinity of, short segments of DNA. The ionization cluster-size distribution and other nanodosimetric quantities, however, are not directly measurable in biological targets and our current knowledge is mostly based on numerical simulations of particle tracks in water, calculating track structure parameters for nanometric target volumes. The assessment of nanodosimetric quantities derived from particle-track calculations using different Monte Carlo codes plays, therefore, an important role for …

Teaching Monte Carlo Codes At University: Development Of A Geant4 Course For Students Of Schools Of Physics, Susanna Guatelli, Dean Cutajar, Anatoly B. Rosenfeld, Catherine Layton

Faculty of Engineering and Information Sciences - Papers: Part A

Nowadays, it is important that students of Schools of Physics include the study of Monte Carlo codes in their curriculum as these codes are widely used in research. At the School of Engineering Physics of the University of Wollongong, we designed and set in place a Geant4 course addressed to the Medical Physics domain. In this paper, we illustrate the main features of the course and its development since 2010. The design of this course maybe adopted to teach Geant4 or any other Monte Carlo code, and in general to teach complex software tools to students with limited computing background. …

Electron Emission From Amorphous Solid Water After Proton Impact: Benchmarking Ptra And Geant4 Track Structure Monte Carlo Simulations, M U. Bug, H Rabus, Anatoly B. Rosenfeld

Faculty of Engineering and Information Sciences - Papers: Part A

Track structure Monte Carlo simulations of ionising radiation in water are often used to estimate radiation damage to DNA. For this purpose, an accurate simulation of the transport of densely ionising low-energy secondary electrons is particularly important, but is impaired by a high uncertainty of the required physical interaction cross section data of liquid water.

A possible tool for the verification of the secondary electron transport in a track structure simulation has been suggested by Toburen et al. (2010), who have measured the angle-dependent energy spectra of electrons, emitted from a thin layer of amorphous solid water (ASW) upon a …

Introduction To The Geant4 Simulation Toolkit, Susanna Guatelli, D Cutajar, Bradley Oborn, Anatoly B. Rosenfeld

Faculty of Engineering - Papers (Archive)

Geant4 is a Monte Carlo simulation Toolkit, describing the interactions of particles with matter. Geant4 is widely used in radiation physics research, from High Energy Physics, to medical physics and space science, thanks to its sophisticated physics component, coupled with advanced functionality in geometry description. Geant4 is widely used at the Centre for Medical Radiation Physics (CMRP), at the University of Wollongong, to characterise and optimise novel detector concepts, radiotherapy treatments, and imaging solutions. This lecture consists of an introduction to Monte Carlo method, and to Geant4. Particular attention will be devoted to the Geant4 physics component, and to the …

The Geant4-Dna Project, S Incerti, G Baldacchino, M Bernal, R Capra, C Champion, Z Francis, S Guatelli, P Gueye, A Mantero, B Mascialino, P Moretto, P Nieminen, Anatoly B. Rosenfeld, C Villagrasa, C Zacharatou

Faculty of Engineering - Papers (Archive)

The Geant4-DNA project proposes to develop an open-source simulation software based and fully included in the general-purpose Geant4 Monte Carlo simulation toolkit. The main objective of this software is to simulate biological damages induced by ionising radiation at the cellular and sub-cellular scale. This project was originally initiated by the European Space Agency for the prediction of deleterious effects of radiation that may affect astronauts during future long duration space exploration missions. In this paper, the Geant4-DNA collaboration presents an overview of the whole ongoing project, including its most recent developments already available in the last Geant4 public release (9.3 …

Validation Of Geant4 Atomic Relaxation Against The Nist Physical Reference Data, S. Guatelli, A. Mantero, B. Mascialino, Maria G. Pia, V. Zampichelli

Faculty of Engineering - Papers (Archive)

The accuracy of the Geant4 component for the simulation of atomic relaxation has been evaluated against the experimental measurements of the NIST Standard Reference Data. The validation study concerns X-ray andAuger transition energies. The comparison of the simulated and experimental data with rigorous statistical methods demonstrates the excellent accuracy of the simulation of atomic de-excitation in Geant4.

Geant4 Atomic Relaxation, Susanna Guatelli, Alfonso Mantero, Barbara Mascialino, Petteri Nieminen, Maria Grazia Pia

Faculty of Engineering - Papers (Archive)

The Low Energy Electromagnetic package of the Geant4 toolkit incorporates a component for the simulation of atomic relaxation of elements with atomic number between 6 and 100. This process is triggered by the creation of a vacancy in the atomic shell occupancy as a result of an incident particle interaction with an atom of the target material. X-ray fluorescence and Auger electron emission result from the relaxation cascade. The availability of a model handling the atomic relaxation in Geant4 extends the applicability of the simulation toolkit to experimental use cases concerning the investigation of material properties through their characteristic X-ray …

Geant4 Simulation For Lhc Radiation Monitoring, M Glaser, S Guatelli, B Mascialino, M Moll, M G. Pia, F Ravotti

Faculty of Engineering and Information Sciences - Papers: Part A

Monitoring radiation background is a crucial task for the operation of LHC experiments. A project is in progress at CERN for the optimisation of the radiation monitors for LHC experiments. A simulation system based on Geant4, designed to assist the engineering optimisation of LHC radiation monitor detectors, is presented. Various detector packaging configurations are studied through their Geant4-based simulation, and their behaviour is compared.

Geant4 Antropomorphic Phantoms, Susanna Guatelli, Barbara Mascialino, Maria Grazia Pia, Witold Pokorski

Faculty of Engineering and Information Sciences - Papers: Part A

A novel architectural approach to the design of human phantom software models is presented. A detailed design has been developed to enable the adoption of this approach in Geant4-based simulation applications. A few preliminary implementations and application demonstrations are described.

Geant4 Simulation In A Distributed Computing Environment, Susanna Guatelli, Alfonso Mantero, Patricia Mendez Lorenzo, Jakub Moscicki, Maria Grazia Pia

Faculty of Engineering and Information Sciences - Papers: Part A

A general system to perform a Geant4-based simulation in a distributed computing environment is presented. The architecture developed makes the system transparent to sequential or parallel execution and to the environment where the simulation is run: a single machine, a local cluster or a geographically distributed grid.

Validation Of The Geant4 Bremsstrahlung Models: First Results, S Chauvie, S Guatelli, B Mascialino, L Pandola, M G. Pia, P Rodrigues, A Trindade

Faculty of Engineering and Information Sciences - Papers: Part A

A project is in progress for a systematic, rigorous validation of Geant4 electromagnetic physics. This paper presents the first results concerning the validation of Geant4 bremsstrahlung models against experimental data.

Models Of Biological Effects Of Radiation In The Geant4 Toolkit, S Chauvie, Z Francis, S Guatelli, S Incerti, G Montarou, P Nieminen, M G. Pia

Faculty of Engineering and Information Sciences - Papers: Part A

A project, named Geant4-DNA, is in progress to extend the Geant4 simulation toolkit to model the effects of radiation with biological systems at cellular and DNA level. The first component implemented in the first development cycle of the project describes the fractional survival of a population of cells irradiated with photons or charged particles. The software system developed provides the user the option to choose among a small set of alternative models for the calculation of mammalian cell survival after irradiation. The flexible design adopted makes the system open to further extension to implement other cell survival models available in …

Validation Of Geant4 Electromagnetic And Hadronic Models Against Proton Data, G A. P Cirrone, G Cuttone, F Di Rosa, S Guatelli, B Mascialino, M G. Pia, G Russo

Faculty of Engineering and Information Sciences - Papers: Part A

A comprehensive, rigorous validation of Geant4 electromagnetic and hadronic models pertinent to the simulation of the proton Bragg peak in water is presented. Geant4 simulation results are validated against high precision experimental data taken in the CATANA hadrontherapy facility.

Comparison Of Geant4 Electromagnetic Physics Models Against The Nist Reference Data, Katsuya Amako, Susanna Guatelli, Vladimir N. Ivanchencko, Michel Maire, Barbara Mascialino, Koichi Murakami, Petteri Nieminen, Luciano Pandola, Sandra Parlati, Maria Grazia Pia, Michela Piergentili, Takashi Sasaki, Laszlo Urban

Faculty of Engineering - Papers (Archive)

The Geant4 Simulation Toolkit provides an ample set of physics models describing electromagnetic interactions of particles with matter. This paper presents the results of a series of comparisons for the evaluation of Geant4 electromagnetic processes with respect to United States National Institute of Standards and Technologies (NIST) reference data. A statistical analysis was performed to estimate quantitatively the compatibility of Geant4 electromagnetic models with NIST data; the statistical analysis also highlighted the respective strengths of the different Geant4 models.