A theoretical investigation of electron and positron scattering from atomic nitrogen over the incident energy range from 1 eV to 1 MeV is presented. Scattering observables, including integrated elastic, momentum transfer, inelastic, ionization, and total cross sections, as well as the Sherman function, are calculated by solving the Dirac relativistic partial-wave equation with a local complex optical potential. Critical minima in the elastic differential cross section and corresponding maxima in the predicted spin polarization are examined in detail. The calculated cross section set is subsequently employed in a Monte Carlo simulation to determine electron transport properties in nitrogen gas for reduced electric fields (E/N) from 1 to 500 Td. Results for the drift velocity, mean energy, and longitudinal diffusion and mobility coefficients are presented and discussed.

The differential, integrated elastic, total (elastic+inelastic), transport (momentum transfer and viscosity), and total ionization cross sections for electron and positron scattering from ethylene ( C_2 H_4 ) molecule are calculated over the energy range of 1 eV−1 MeV. This report also provides the spin polarization data for the same scattering systems. Independent atom model (IAM) and the screening correction enclosed by the same model (IAMS) are used for the present work. Dirac partial wave analysis is used to compute the scattering observables, using a complex optical model potential (OMP). Comparison of our calculations with the experimental and theoretical results, available in the literature, has been made. This investigation shows the effectiveness of the IAMS, to describe the electron and positron scattering by C_2 H_4 . Scattering observables of electron-ethylene interactions

Abstract The scattering of electrons and positrons from neutral Zn atoms is studied in the incident energy range 1 eV to 1 MeV using a relativistic Dirac partial wave method combined with a complex optical-model potential. Within this framework, differential cross sections (DCS), angle-integrated cross sections, and the Sherman function are computed for both projectiles. The calculations reveal four pronounced critical minima (CM) in the electron DCS at ( 11.22 eV , 92.31 ∘ ) , ( 86.09 eV , 147.54 ∘ ) , ( 162.90 eV , 73.69 ∘ ) , and ( 347.10 eV , 124.00 ∘ ) , while no corresponding minima are observed for positron scattering. This difference is mainly due to the absence of exchange effects in the positron case. Analysis shows that the electron CM originate from relativistic interference between spin–orbit interaction channels, which strongly reduces the direct scattering amplitude. Consequently, very strong spin polarization occurs near these minima, with eight of the nine polarization maxima greater than 96 % , whereas positron polarization remains small across the whole energy range. Comparison with available measurements and previous theoretical results demonstrates reasonable agreement.

This work provides a comprehensive theoretical investigation of e^--CH_4 and e^+-CH_4 scattering systems over a wide range of projectile energies, from 1 eV to 1 MeV. The single scattering independent atom model (IAM) and the screening correction (IAMS), arising from a semi-classical analysis of atomic geometrical overlap, are used within the same framework for the present analysis. A broad spectrum of scattering observable quantities is calculated, such as differential, integrated elastic, momentum transfer, viscosity, inelastic, grand total and total ionization cross sections along with the Sherman function. For this spin-dependent and relativistic scattering study, the Dirac equation is solved using a complex optical potential model (OPM) by partial wave phase-shift analysis to generate the scattering cross-sections data. A satisfactory level of concordance is observed when our computed results are compared to both experimental data and other theoretical calculations available in the literature. The screening corrected independent atom model (IAMS) has been found to produce results with greater accuracy than the IAM. Comparison of scattering cross sections (a) DCS in units of a_0^2/sr at 90°scattering angle, (b) Sherman function S(θ) at 90°scattering angle, (c) TCS, (d) IECS, (e) TICS and (f) MTCS in units of a_0^2 .

In this study, the Dirac relativistic wave equation was utilized within the framework of optical potential model to calculate differential and angle-integrated cross-sections for the elastic scattering of electrons and positrons by germanium atoms across a wide energy range of 1 eV to 1 MeV. Comprehensive analyses were conducted to determine the energy dependence of various cross-sections, including total cross-section, viscosity crosssection, inelastic cross-section, ionization cross-section, integral elastic cross-section, and momentum transfer cross-section. Additionally, spin-asymmetry parameters U(6) and T(6), as well as the Sherman function S(6), were calculated. For the first time, critical minima in the distribution of elastic differential cross sections and the associated maximum spin polarization for electron impact scattering have been studied for this element. The results obtained in this work show reasonable agreement with existing experimental and theoretical data.

By employing previous models [1, 2], we report the differential, integrated elastic, inelastic, total (elastic+inelastic), viscosity and momentum transfer cross sections of e(+/-) - C2H2 collision dynamics, for the energy range of 1 eV-1 MeV. This report also incorporates Sherman spin polarization function and total ionization cross section. This work provides the first comprehensive study of electron/positron scattering from C2H2 over such a wide energy range. A complex optical model potential (OMP) has been used to represent the projectile-atom interaction. Relativistic Dirac equation has been solved, to get phase-shifts, needed for the calculations of scattering observables, using OMP. Our results are compared with the existing experimental data and theoretical calculations.

A theoretical calculation on the elastic and inelastic scattering of electrons and positrons in water molecule is performed for incident energies ranging from 1 eV - 10 keV. Dirac relativistic partial-wave method with a complex optical potential for free-atoms is adopted. Various scattering observables are obtained by taking into account the geometrical screening corrections due to partial overlapping of constituent atoms, as seen by the incident projectiles in the coherent sum of scattering amplitudes. Furthermore, the Monte Carlo method is used to calculate the transport characteristics of electrons in H _2 O vapor for electric field E/N = 1-300 Td, taking into account inelastic collisions. The drift velocity, average electron energy, ionization coefficient and mobility coefficients are calculated. Admixtures of 2

ABSTRACT This study presents a comprehensive theoretical investigation into the scattering of electrons and positrons from nitrogen dioxide (NO 2 ) molecules across a broad energy ranging from 1 eV to 1 MeV. The focus of the analysis encompasses a variety of cross‐sections, including differential, integrated elastic, inelastic, total ionization, total, momentum transfer and viscosity. Additionally, the study explores the spin polarization effects within electron/positron‐NO 2 scattering events. Utilizing a combination of relativistic Dirac partial wave analysis, the independent atom model (IAM), and the screening adjusted independent atom model (IAMS), this research achieves a refined understanding of scattering mechanisms. Comparative assessments with prior theoretical and empirical findings reveal that the IAM approach yields lesser accuracy at lower energies, while maintaining commendable agreement with existing data at medium to high energies. The insights and methodologies developed herein are anticipated to contribute significantly to the advancement of future research in this domain.

This review reports on the scattering of electrons (e(-)) and positrons (e(+)) with few precious metal atoms, namely Al, Ni, Cu, Ag, Pt, and Au over the impact energies 1 eV <= E-i <= 1 MeV. Elastic scattering cross sections-differential, integral, momentum-transfer, and viscosityare presented, and Ionization, inelastic, and total (sum of elastic and inelastic) scattering cross sections are also included. In addition, a systematic analysis of the critical minima in the elastic differential cross sections along with the positions of the corresponding total polarization points in the Sherman function, a phase-sensitive quantity, is furnished. We employ the relativistic Dirac partial wave phase-shift analysis embodying a well-established complex optical-potential model (OPM). The interactions of the incident leptons with both the nucleus and the bound electrons of the target are included in the present OPM approach. The comparison with both the theoretical and the experimental data demonstrates the merit of our proposed method in explaining the details of calculations except in the very low energy region.

Calculations are presented for elastic differential and integrated cross-sections like elastic, momentum transfer, viscosity, inelastic, total (elastic + inelastic) and total ionization along with the Sherman functions for electrons and positrons scattering from hydrogen isonuclear series at incident energies from 1 eV to 1 MeV. To describe the scattering from neutral atoms, this work employs the relativistic Dirac partial wave (phase-shift) analysis with a short-range complex optical-potential model (OPM), comprising static, polarization, exchange (for electrons only), and absorption potentials. This potential is supplemented by the modified Coulomb potential for the same purpose for a charged atom. A reasonable agreement is found when we compare our computed results with available experimental data and other theoretical computations.

The elastic scattering of electrons and positrons by beryllium atoms and its isonuclear ion states is described in this paper in terms of differential and various angle integrated cross sections. For this element, the critical minima in the elastic differential cross sections and the optimum spin polarization sites are found. These calculations are performed using the Dirac partial wave analysis (DPWA) and a projectile-target modified complex optical model potential. Further, the Monte Carlo method is used to calculate the transport characteristics of electrons in a mixture of inert gas (He, Ar) and beryllium vapor for electric field values E/N = 1-100 Td, taking into account inelastic collisions. We studied the effect of metal vapor concentration on drift velocity, average electron energy, diffusion and mobility coefficients. Finally, we investigated the effect of beryllium vapor on the electron energy distribution function in the inert gas. On comparing present work with existing theoretical calculation, a reasonable agreement is observed.

The present work reports the theoretical investigation of the scattering of electrons and positrons by the ethane (C2H6) molecule over the energy range 1 eV–1 MeV. The investigation was carried out by taking into account the screening correction arising from a semiclassical analysis of the atomic geometrical overlapping of the scattering observables calculated in the independent atom approximation. The study is presented through the calculations of a broad spectrum of observable quantities, namely differential, integrated elastic, momentum transfer, viscosity, inelastic, grand total, and total ionization cross-sections and the Sherman functions. A comparative study was carried out between scattering observables for electron impact with those for positron impact to exhibit the similarity and dissimilarity arising out of the difference of the collisions of impinging projectiles with the target. Partial-wave decomposition of the scattering states within the Dirac relativistic framework employing a free-atom complex optical model potential was used to calculate the corresponding observable quantities of the constituent atoms. The results, calculated using our recipe, were compared with the experimental and theoretical works available in the literature. The Sherman function for a e±–C2H6 scattering system is presented for the first time in the literature. The addition of the screening correction to the independent atom approximation method was found to substantially reduce the scattering cross-sections, particularly at forward angles for lower incident energies.

This work reports on the differential and various angle integrated cross sections for the scattering of electrons and positrons by silicon atoms. Moreover, the Sherman function S(θ ) and two other spin asymmetry parameters U(θ ) and T(θ ) have been calculated. Critical minima in the elastic differential cross sections and maximum spin polarization points were identified for this element. Dirac partial wave method with a complex optical model potential is used to carry out these investigations. Transport characteristics of electrons in silicon vapors and mixtures of inert gases (helium, argon) with silicon vapor were calculated using the Monte Carlo method. For electric field strengths ranging from 1 to 100 Td, drift velocity, average electron energy, diffusion and mobility coefficients, and electron energy distribution function are studied. We have shown that impurities of silicon vapor significantly affect electron transport in noble gases.

A theoretical investigation of differential, integrated elastic, inelastic, transport (momentum transfer & viscosity), grand total (elastic+inelastic) and total ionisation cross-sections along with the Sherman functions for the scattering of electron and positron by hydrogen cyanide (HCN) in the energy range 1 eV - 1MeV are presented in this report. We perform calculations using the single scattering independent atom model (IAM) and IAM with screening correction (IAMS). The scattering observables are calculated using a complex optical model potential in the framework of the Dirac partial wave analysis (DPWA). The inclusion of screening correction to the IAM appreciably improves the cross-sections, especially at low-impact energies. Our calculated results are compared with the available experimental and theoretical works found in the literature. Our present computational data agree well with prior results. [GRAPHICS] .

This article incorporates details of our calculations of the observable quantities for the scattering of electrons and positrons from a post transition metal Thallium (Tl), in the energy range of 1 eV ≤ Ei ≤ 1 MeV, using the relativistic Dirac partial wave (phase-shift) analysis employing a complex optical-potential. Absolute differential, integrated elastic and inelastic, transport, total ionization, and total cross sections and a thorough study of the critical minima in the elastic differential cross sections along with the associated angular positions of the maximum polarization points in the Sherman function are provided to study the collision dynamics. The optical potential model incorporates the interactions of the incident electron and/or positron with both the nucleus and the bound electrons of the target atom. In-depth analyses of the spin asymmetry, which are sensitive to phases related interference effect, brought on by the various ingredients of the lepton-atom interaction, are also presented. The performance of the current approach to explain the observations, with the exception of the extremely low energy domain, is shown by a comparison of the previous experimental and theoretical results on this target atom.

This article presents a theoretical investigation of the differential, integrated, elastic, inelastic, total, momentum-transfer, and viscosity cross-sections, along with the total ionization cross-section, for elastically scattered electrons and positrons from a carbon dioxide (CO2) molecule in the incident energy range of 1 eV ≤Ei≤ 1 MeV. In addition, for the first time, we report the spin polarization of e±−CO2 scattering systems. The independent atom model (IAM) with screening correction (IAMS) using a complex optical potential was employed to solve the Dirac relativistic equation in partial-wave analysis. The comparison of our results with the available experimental data and other theoretical predictions shows a reasonable agreement in the intermediate- and high-energy regions.

Theoretical investigation of the scattering of electrons and positrons from the plasma etching gas trifluoroiodomethane (CF3I) is presented in the present work. The investigation is carried out by taking into account the screening correction arising from a semiclassical analysis of atomic geometrical overlapping of the scattering cross-sections calculated in the independent atom approximation. The scattering system e±-CF3I is studied through the calculations of the observable quantities, namely, absolute differential, Sherman function, total elastic and inelastic, momentum transfer, viscosity, ionization and total cross sections over the energy range 1 eV–1 MeV. Energy dependency of the differential cross section and Sherman function are also picturized in this work. A comparative study is carried out between scattering observables for electron impact with those for positron impact to get a better understanding of the interaction and dynamics of the collision process. The corresponding scattering quantities of the constituent atoms are calculated employing a complex optical model potential by solving the Dirac relativistic wave equations in the framework of partial wave analysis. The comparison of our results with the available experimental and theoretical data shows a reasonable agreement.

The differential, integrated elastic, total and momentum transfer cross sections along with Sherman function for the elastic scattering of electrons and positrons by cadmium atoms have been evaluated from the partial wave solution of the Dirac relativistic scattering equations for a projectile-atom complex potential at the energy range 6.4 eV < E < 1.0 keV. For various scattering quantities, a comparison of our results exhibits better agreement with the experimental data than the other available theoretical values.

The theoretical investigation of differential, integrated elastic, momentum transfer, viscosity, inelastic, grand total and total ionisation cross sections along with the Sherman functions for the scattering of electrons and positrons by polar NH3 molecule in the energy range 1 eV-1 MeV are reported in the present work. We carry out calculations using the independent atom model (IAM) and IAM with screening correction. The scattering observables are calculated using a complex optical model potential in the framework of the Dirac partial wave analysis. The application of screening correction to the IAM substantially improves the cross sections particularly at lower incident energies. The results obtained from the present study are compared with the available experimental and theoretical works found in the literature.

The current study investigates the scattering of electrons and positrons from aluminum isonuclear series within the framework of the Dirac relativistic partial wave analysis. For the neutral aluminum atoms, the scattering phenomena are described by employing a short-range complex optical potential. For the ionic series, on the other hand, this potential is supplemented by the Coulomb potential. The calculations are reported for the differential cross-section, total cross-section, integrated elastic cross-section, inelastic cross-section, momentum transfer cross-section, viscosity cross-section, and total ionization cross-section over the energy range 1 eV ≤ E i ≤ 1 MeV. The Sherman function S and spin asymmetry parameters T and U are also predicted for the same scattering systems over the same energy range. In addition, for the first time, we report a systematic study of the critical minima in the differential cross sections as well as the associated maximum spin polarization points in the Sherman function. We also compute the inelastic, elastic, momentum transfer, viscosity and total mean free paths for the aforesaid scattering systems. The Coulomb glory effect, the amplification of elastic backscattering of electrons from positive ions, is examined throughout the ionic series of aluminum. A comparison of our results to the reported theoretical and experimental studies reveals a good consistency over the compared energy range. The present theoretical method is thus expected to be useful for the fast generation of accurate cross-sections needed in many areas of science, technologies, and industries.