scholarly journals The hybrid model for sampling multiple elastic scattering angular deflections based on Goudsmit-Saunderson theory

2017 ◽  
Vol 32 (3) ◽  
pp. 229-235 ◽  
Author(s):  
Muhammad Wasaye ◽  
Hui Wang ◽  
Huaqing Zheng ◽  
Pengcheng Long ◽  
Hamza Naeem
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Angular Distribution ◽  
Elastic Scattering ◽  
Multiple Scattering ◽  
Cross Sections ◽  
Rejection Sampling ◽  
Radiation Process ◽  
Low Energy Electrons ◽  
Path Lengths

An algorithm for the Monte Carlo simulation of electron multiple elastic scattering based on the framework of SuperMC (Super Monte Carlo simulation program for nuclear and radiation process) is presented. This paper describes efficient and accurate methods by which the multiple scattering angular deflections are sampled. The Goudsmit-Saunderson theory of multiple scattering has been used for sampling angular deflections. Differential cross-sections of electrons and positrons by neutral atoms have been calculated by using Dirac partial wave program ELSEPA. The Legendre coefficients are accurately computed by using the Gauss-Legendre integration method. Finally, a novel hybrid method for sampling angular distribution has been developed. The model uses efficient rejection sampling method for low energy electrons (<500 keV) and larger path lengths (>500 mean free paths). For small path lengths, a simple, efficient and accurate analytical distribution function has been proposed. The later uses adjustable parameters determined from the fitting of Goudsmith-Saunderson angular distribution. A discussion of the sampling efficiency and accuracy of this newly developed algorithm is given. The efficiency of rejection sampling algorithm is at least 50 % for electron kinetic energies less than 500 keV and longer path lengths (>500 mean free paths). Monte Carlo Simulation results are then compared with measured angular distributions of Ross et al. The comparison shows that our results are in good agreement with experimental measurements.

Electron Scattering in Solids

1990 ◽  
Vol 48 (2) ◽  
pp. 4-5
Author(s):  
Ryuichi Shimizu ◽  
Ze-Jun Ding
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Angular Distribution ◽  
Elastic Scattering ◽  
Electron Scattering ◽  
Cross Sections ◽  
Expansion Method ◽  
Electron Excitation ◽  
Partial Wave Expansion ◽  
Backscattered Electrons

Monte Carlo simulation has been becoming most powerful tool to describe the electron scattering in solids, leading to more comprehensive understanding of the complicated mechanism of generation of various types of signals for microbeam analysis.The present paper proposes a practical model for the Monte Carlo simulation of scattering processes of a penetrating electron and the generation of the slow secondaries in solids. The model is based on the combined use of Gryzinski’s inner-shell electron excitation function and the dielectric function for taking into account the valence electron contribution in inelastic scattering processes, while the cross-sections derived by partial wave expansion method are used for describing elastic scattering processes. An improvement of the use of this elastic scattering cross-section can be seen in the success to describe the anisotropy of angular distribution of elastically backscattered electrons from Au in low energy region, shown in Fig.l. Fig.l(a) shows the elastic cross-sections of 600 eV electron for single Au-atom, clearly indicating that the angular distribution is no more smooth as expected from Rutherford scattering formula, but has the socalled lobes appearing at the large scattering angle.

Monte Carlo Simulation Of X-Ray Spectra In Absolute Units In The Energy Regime Between 1 And 50 Kev

1999 ◽  
Vol 5 (S2) ◽  
pp. 82-83
Author(s):  
C. O. Schiebl ◽  
V. Ambrose ◽  
J. Wernisch
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Elastic Scattering ◽  
Cross Sections ◽  
Shape Function ◽  
Single Scattering ◽  
Stopping Power ◽  
X Ray ◽  
Electron Energy Loss ◽  
Monte Carlo Simulation Program

SeSAME, a Monte Carlo simulation program which can handle totally arbitrarily shaped twodimensional geometries, has been extended for the modeling of whole x-ray spectra in absolute units. The so called single scattering model has been used for the simulations presented here. Elastic scattering processes are modeled using a partial wave approach according to a relativistic expression derived by Mott. For the calculation of the electron energy loss the stopping power formula from Joy and Luo has been applied.Two different double differential cross sections for continuous x-ray production have been implemented into SeSAME. The first one is an analytical model derived by Kirkpatrick and Wiedmann and is based on a non-relativistic theory developed by Sommerfield and Elwert. The second one uses tabulated values for the shape function for atomic-field Bremsstrahlung and scaled Bremsstrahlung cross sections differential only in photon energy according to Kissel at al.

Development of SiO2 based doped with LiF, Cr2O3, CoO4 and B2O3 glasses for gamma and fast neutron shielding

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Bünyamin Aygün ◽  
Erdem Şakar ◽  
Abdulhalik Karabulut ◽  
Bünyamin Alım ◽  
Mohammed I. Sayyed ◽  
...  
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Fast Neutron ◽  
Cross Sections ◽  
Gamma Ray ◽  
Absorbed Dose ◽  
Neutron Shielding ◽  
Shielding Properties ◽  
Effective Neutron ◽  
Simulation Codes

AbstractIn this study, the fast neutron and gamma-ray absorption capacities of the new glasses have been investigated, which are obtained by doping CoO,CdWO4,Bi2O3, Cr2O3, ZnO, LiF,B2O3 and PbO compounds to SiO2 based glasses. GEANT4 and FLUKA Monte Carlo simulation codes have been used in the planning of the samples. The glasses were produced using a well-known melt-quenching technique. The effective neutron removal cross-sections, mean free paths, half-value layer, and transmission numbers of the fabricated glasses have been calculated through both GEANT4 and FLUKA Monte Carlo simulation codes. Experimental neutron absorbed dose measurements have been carried out. It was found that GS4 glass has the best neutron protection capacity among the produced glasses. In addition to neutron shielding properties, the gamma-ray attenuation capacities, were calculated using newly developed Phy-X/PSD software. The gamma-ray shielding properties of GS1 and GS2 are found to be equivalent to Pb-based glass.

scholarly journals Monte Carlo simulation of halos in the crystal clouds

2021 ◽  
Vol 2099 (1) ◽  
pp. 012067
Author(s):  
Q Mu ◽  
E G Kablukova ◽  
B A Kargin ◽  
S M Prigarin
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Monte Carlo Method ◽  
Ray Tracing ◽  
Multiple Scattering ◽  
Radiation Transfer ◽  
Cirrus Clouds ◽  
Ice Crystals ◽  
The Sun ◽  
Different Shapes

Abstract In this paper, we try to answer the question: how the multiple scattering, the sun elevation, shape and orientation of ice crystals in the cirrus clouds affect a halo pattern. To study the radiation transfer in optically anisotropic clouds, we have developed the software based on Monte Carlo method and ray tracing. In addition to halos, this software enables one to simulate “anti-halos”, which above the cloud layer can be seen by observers. We present the visualization of halos and anti-halos generated by the cirrus clouds for different shapes and orientations of ice crystals.

Monte-Carlo simulation of single-line resonance scattering in a rarefied gas

1991 ◽  
Vol 69 (8-9) ◽  
pp. 1146-1153 ◽  
Author(s):  
I. D. Lockerbie ◽  
W. S. C. Brooks ◽  
P. How ◽  
E. J. Llewellyn
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Multiple Scattering ◽  
Rarefied Gas ◽  
Resonant Scattering ◽  
Resonance Scattering ◽  
Single Line ◽  
Gas Temperature ◽  
Line Shapes ◽  
Simulation Results

A Monte-Carlo simulation of single-line resonant scattering in a rarefied gas is presented and the technique is applied to the interpretation of a rocket-borne resonance-lamp experiment. The simulation examines the case of an emitting and absorbing gas at the same temperature for a number of detector and source configurations. The distance from the last scatter point, the angular distribution of the detected scattered photons, and the line shape formed by the scattered photons, at the detector, are evaluated for these different configurations. The simulation results suggest that the scattering of the detected photon occurs very near to the rocket, and not necessarily in the traditional scattering region at the intersection of the detector and emitter normals. It is observed that multiple scattering plays an important role in the number of photons detected and that the apparent gas temperature, as exhibited by the line shapes of the scattered photons, is dependent upon the configuration of the experiment. The simulation results suggest that, for a resonance-scattering experiment to measure constituent concentrations, the experimental design must optimize the return signal and minimize the effect of multiple scattering. The results also suggest that the calibration procedures for resonance-scattering experiments must be made with a physical configuration and environment that is identical to that expected in the rocket flight.

Sign in / Sign up

Export Citation Format

Share Document