On learning particle distributions in the 1D implicit Monte Carlo simulations of radiation transport

2020 ◽  
Author(s):  
Anna Matsekh ◽  
Luis Chacon ◽  
HyeongKae Park ◽  
Guangye Chen
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Simulations ◽  
Radiation Transport ◽  
Particle Distributions

Reduced order modeling for accelerated Monte Carlo simulations in radiation transport

2015 ◽  
Vol 267 ◽  
pp. 237-251 ◽  
Author(s):  
Indika Udagedara ◽  
Brian Helenbrook ◽  
Aaron Luttman ◽  
Stephen E. Mitchell
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Simulations ◽  
Radiation Transport ◽  
Reduced Order Modeling ◽  
Reduced Order

Assessment of secondary neutrons in particle therapy by Monte Carlo simulations

2021 ◽  
Author(s):  
José Vedelago ◽  
Federico A Geser ◽  
Iván D Muñoz ◽  
Alberto Stabilini ◽  
Eduardo G Yukihara ◽  
...  
Keyword(s):  
Monte Carlo ◽  
Angular Distribution ◽  
Monte Carlo Simulations ◽  
Radiation Transport ◽  
Heavy Ion ◽  
High Energy ◽  
Particle Therapy ◽  
Carbon Ions ◽  
Secondary Neutron ◽  
Secondary Neutrons

Abstract Objective: The purpose of this study is to estimate the energy and angular distribution of secondary neutrons inside a phantom in hadron therapy, which will support decisions on detector choice and experimental setup design for in-phantom secondary neutron measurements. Approach: Dedicated Monte Carlo simulations were implemented, considering clinically relevant energies of protons, helium and carbon ions. Since scored quantities can vary from different radiation transport models, the codes FLUKA, TOPAS and MCNP were used. The geometry of an active scanning beam delivery system for heavy ion treatment was implemented, and simulations of pristine and spread-out Bragg peaks were carried out. Previous studies, focused on specific ion types or single energies, are qualitatively in agreement with the obtained results. Main results: The secondary neutrons energy distributions present a continuous spectrum with two peaks, one centred on the thermal/epithermal region, and one on the high-energy region, with the most probable energy ranging from 19 MeV up to 240 MeV, depending on the ion type and its initial energy. The simulations show that the secondary neutron energies may exceed 400 MeV and, therefore, suitable neutron detectors for this energy range shall be needed. Additionally, the angular distribution of the low energy neutrons is quite isotropic, whereas the fast/relativistic neutrons are mainly scattered in the down-stream direction. Significance: It would be possible to minimize the influence of the heavy ions when measuring the neutron-generated recoil protons by selecting appropriate measurement positions within the phantom. Although there are discrepancies among the three Monte Carlo codes, the results agree qualitatively and in order of magnitude, being sufficient to support further investigations with the ultimate goal of mapping the secondary neutron doses both in- and out-of-field in hadrontherapy. The obtained secondary neutron spectra are available as supplementary material.

An Investigation of Solar Trees for Effective Sunlight Capture Using Monte Carlo Simulations of Solar Radiation Transport

2014 ◽  
Author(s):  
Navni N. Verma ◽  
Sandip Mazumder
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Simulations ◽  
Radiation Flux ◽  
Radiation Transport ◽  
Dimensional Space ◽  
Global Radiation ◽  
Three Dimensional ◽  
Capture Efficiency ◽  
Solar Photovoltaic ◽  
Three Dimensional Space

Solar photovoltaic cells arranged in complex three-dimensional leaf-like configurations — referred to as a solar tree — can potentially collect more sunlight than traditionally used flat configurations. It is hypothesized that this could be because of two reasons. First, the three-dimensional space can be utilized to increase the overall surface area over which the sunlight may be captured. Second, as opposed to traditional flat panel configurations where the capture efficiency decreases dramatically for shallow angles of incidence, the capture efficiency of a solar tree is hampered little by shallow angles of incidence due to the three-dimensional orientation of the solar leaves. In this paper, high fidelity Monte Carlo simulation of radiation transport is conducted to gain insight into whether the above hypotheses are true. The Monte Carlo simulations provide local radiation flux distributions in addition to global radiation flux summaries. The studies show that except for near-normal solar incidence angles, solar trees capture sunlight more effectively than flat panels — often by more than a factor of 5. The Monte Carlo results were also interpolated to construct a daily sunlight capture profile both for mid-winter and mid-summer for a typical North American city. During winter, the solar tree improved sunlight capture by 227%, while in summer the improvement manifested was 54%.

Low-voltage EDS of magnesium ferrite Dendrites in a FEG-SEM

1996 ◽  
Vol 54 ◽  
pp. 478-479
Author(s):  
Matthew T. Johnson ◽  
Ian M. Anderson ◽  
Jim Bentley ◽  
C. Barry Carter
Keyword(s):  
Monte Carlo ◽  
Quantitative Analysis ◽  
Monte Carlo Simulations ◽  
Cross Section ◽  
Spatial Resolution ◽  
Low Voltage ◽  
Magnesium Ferrite ◽  
X Ray ◽  
Interaction Volume ◽  
Ferrite Spinel

Energy-dispersive X-ray spectrometry (EDS) performed at low (≤ 5 kV) accelerating voltages in the SEM has the potential for providing quantitative microanalytical information with a spatial resolution of ∼100 nm. In the present work, EDS analyses were performed on magnesium ferrite spinel [(MgxFe1−x)Fe2O4] dendrites embedded in a MgO matrix, as shown in Fig. 1. spatial resolution of X-ray microanalysis at conventional accelerating voltages is insufficient for the quantitative analysis of these dendrites, which have widths of the order of a few hundred nanometers, without deconvolution of contributions from the MgO matrix. However, Monte Carlo simulations indicate that the interaction volume for MgFe2O4 is ∼150 nm at 3 kV accelerating voltage and therefore sufficient to analyze the dendrites without matrix contributions.Single-crystal {001}-oriented MgO was reacted with hematite (Fe2O3) powder for 6 h at 1450°C in air and furnace cooled. The specimen was then cleaved to expose a clean cross-section suitable for microanalysis.

MONTE CARLO SIMULATIONS OF ELECTRON DRIFT VELOCITIES IN THE NOBLE GASES AND THEIR MIXTURES

1979 ◽  
Vol 40 (C7) ◽  
pp. C7-63-C7-64
Author(s):  
A. J. Davies ◽  
J. Dutton ◽  
C. J. Evans ◽  
A. Goodings ◽  
P.K. Stewart
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Simulations ◽  
Noble Gases ◽  
Electron Drift
Sign in / Sign up

Export Citation Format

Share Document