Electron Scattering in Solids

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.

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

Nuclear Technology and Radiation Protection ◽

10.2298/ntrp1703229w ◽

2017 ◽

Vol 32 (3) ◽

pp. 229-235 ◽

Cited By ~ 1

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.

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Angular distribution of optical photons from β decay of oriented nuclei

Canadian Journal of Physics ◽

10.1139/p94-032 ◽

1994 ◽

Vol 72 (5-6) ◽

pp. 210-214 ◽

Cited By ~ 2

Author(s):

A. M. Al-Harkan

Keyword(s):

Monte Carlo Simulation ◽

Monte Carlo ◽

Angular Distribution ◽

Electron Scattering ◽

Pure Water ◽

Β Decay ◽

Secondary Electrons ◽

Transparent Media ◽

Optical Photons ◽

Polarization States

Internal and external optical bremsstrahlung accompanying the β decay of polarized nuclei were investigated. The features of angular distribution of light photons were analyzed taking into account multiple electron scattering. Monte-Carlo simulation was used to study the fate of β electrons and to calculate the intensity and angular distribution of the optical photons. It is shown that in pure water, the contribution of secondary electrons in the production of photons reaches 30–40%. We suggest using the angular distribution of optical photons to study the polarization states of β isotopes imbedded in transparent media.

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Erratum: Angular distribution of optical photons from β decay of oriented nuclei

Canadian Journal of Physics ◽

10.1139/p94-091 ◽

1994 ◽

Vol 72 (9-10) ◽

pp. 697-701

Author(s):

A. M. Al-Harkan

Keyword(s):

Monte Carlo Simulation ◽

Monte Carlo ◽

Angular Distribution ◽

Electron Scattering ◽

Pure Water ◽

Β Decay ◽

Secondary Electrons ◽

Transparent Media ◽

Optical Photons ◽

Polarization States

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

Microscopy and Microanalysis ◽

10.1017/s1431927600013738 ◽

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.

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Applications of Monte Carlo Simulation of Electron Scattering to Quantitative X-Ray Microanalyses

Microscopy and Microanalysis ◽

10.1017/s1431927600029524 ◽

2001 ◽

Vol 7 (S2) ◽

pp. 690-691

Author(s):

Kenji Murata ◽

Masaaki Yasuda ◽

Syunji Yamauchi

Keyword(s):

Monte Carlo Simulation ◽

Monte Carlo ◽

Elastic Scattering ◽

Energy Loss ◽

Cross Section ◽

Electron Scattering ◽

List Type ◽

Discrete Energy ◽

X Ray ◽

Loss Process

Monte Carlo simulation of electron scattering has been widely used in various fields such as microanalysis, microscopy and microlithography. Various simulation models have been reported so far. in applications to quantitative x-ray microanalysis the accuracy of the model has been significantly improved by introducing the Mott cross section. However, in the analyses at low energies of an electron beam or at energies near the x-ray excitation energy, the simulation accuracy becomes worse. This is probably because the discrete energy loss process is not incorporated into the simulation model. to improve this default, we developed the model which includes the discrete energy loss process[l]. The outline of the model is described in the following.1)Elastic scatteringWe used the Mott cross section. The Mott cross sections for Al, Cu, Ag and Au elements are calculated at various energies. From this data base we obtain the differential elastic scattering cross section and the total elastic cross section for arbitarary elements and energies by using the interporation or the extrapolation.

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Preliminary Investigation of Microdosimetric Track Structure Physics Models in Geant4-DNA and RITRACKS

Computational and Mathematical Methods in Medicine ◽

10.1155/2015/968429 ◽

2015 ◽

Vol 2015 ◽

pp. 1-8 ◽

Cited By ~ 3

Author(s):

Michael Douglass ◽

Scott Penfold ◽

Eva Bezak

Keyword(s):

Monte Carlo Simulation ◽

Monte Carlo ◽

Cross Sections ◽

Preliminary Investigation ◽

Electron Excitation ◽

Current Work ◽

Track Structure ◽

Interaction Cross Sections

The major differences between the physics models in Geant4-DNA and RITRACKS Monte Carlo packages are investigated. Proton and electron ionisation interactions and electron excitation interactions in water are investigated in the current work. While these packages use similar semiempirical physics models for inelastic cross-sections, the implementation of these models is demonstrated to be significantly different. This is demonstrated in a simple Monte Carlo simulation designed to identify differences in interaction cross-sections.

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

Radiochimica Acta ◽

10.1515/ract-2020-0067 ◽

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.

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