Special Issue "Many-Particle Dynamics in Collisions of Electrons, Positrons and Photons"

A special issue of Atoms (ISSN 2218-2004).

Deadline for manuscript submissions: 2 December 2022 | Viewed by 3550

Special Issue Editors

Dr. Dhanoj Gupta
E-Mail Website
Guest Editor
Department of Physics, School of Advanced Sciences, Vellore Institute of Technology, Vellore, Tamil Nadu 632014, India
Interests: atomic, molecular and optical physics; electron and positron collision physics; fundamental processes in low temperature plasmas; ion trapping and its dynamics in an electrostatic traps
Dr. Suvam Singh
E-Mail Website
Guest Editor
Max Planck Institute for Nuclear Physics, Saupfercheckweg 1, 69117 Heidelberg, Germany
Interests: atomic and molecular physics; physics of atoms/molecules/ions of astrophysical, plasma, and fundamental interest; theoretical investigations of quantum collisions involving electron, positron, and photon scattering from atoms, molecules, and their ions
Dr. Paresh Modak
E-Mail Website
Guest Editor
Physics, Kansas State University, Manhattan, KS 66502, USA
Interests: electron induced collision processes for atoms/molecules and their ions; strong field ionization

Special Issue Information

Dear Colleagues,

When cosmic rays and solar radiation travel through the molecular mediums of the universe, several processes viz. molecular excitation (rovibrational, electronic), ionization, bond dissociation, etc. occur.  These processes end up generating a flux of electrons, photons, charged species (anion, cation), intermediate unstable species and neutral atoms, and smaller molecules. The secondary photons further interact with the surrounding medium producing secondary electrons, charged particles, ions, radicals, electromagnetic radiation, etc. Furthermore, the interaction of solar radiation with the interstellar gas clouds, or with the upper atmosphere of a planet, initiates photochemistry in these environments. The primary processes occurring in this medium are photoionization and photodetachment followed by absorption of radiation.  Thus, the data of molecular photo-processes bear the signatures of molecular species and hence the molecular environments. Therefore, such data are of primary interest to several fields of applied sciences including aeronomy, planetary science, interstellar molecular clouds, the solar nebula, radiation chemistry-physics, biology, dosimetry, radiation therapy, health physics, electron and X-ray microscopy, and photoelectron spectroscopy, etc. In the current scenario, it is also widely recognized that there are new technological advances in plasma processing and the utilization of plasmas in general, ranging from plasma medicine to material processing. These developments are based on the manipulation of plasma properties which in turn requires a detailed understanding of the atomic and molecular processes within plasmas. The collisions of electrons with atoms, molecules, ions, and surfaces are of fundamental importance in low-temperature plasmas, with numerous applications in plasma science and technologies.

Moreover, electron-induced collisions with biomolecules have geared up essentially due to their importance in radiobiology for understanding the radio-induced damages to live tissues. Understanding the underlying physics of such irradiations requires the full description of collisional processes induced by the radiative beam on the target under consideration. In addition to this, the advancement of laser technology and the development of coherent light sources make it possible to probe the molecules with a high level of sophistication. To analyze these experimental data, we need theoretical advancement as well. Thus, there is a burning need for theoretical development as well.

In this edition of special Issue we invite original contributions covering all aspects of electron, positron and photon interaction with atoms, molecules, ions and surfaces both from experimental and theoretical point of view. Such data are of high demand  in plasma science, radiation physics and astrophysics and astronomy. Accurate calculations of some metastable ions are also welcome.

Dr. Dhanoj Gupta
Dr. Suvam Singh
Dr. Paresh Modak
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Atoms is an international peer-reviewed open access quarterly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1500 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • electron collision
  • positron collision
  • photon collision
  • ionization
  • excitation
  • elastic scattering
  • photoionization
  • positronium formation

Published Papers (5 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

Article
Low-Energy Electron Scattering from c-C4F8
Atoms 2022, 10(2), 63; https://doi.org/10.3390/atoms10020063 - 14 Jun 2022
Viewed by 345
Abstract
Electron collision cross-sections of c-C4F8 were investigated at low energies by using the R-matrix method. The static exchange (SE), static exchange with polarization (SEP), and close-coupling (CC) models of the R-matrix method were used for the calculation of the [...] Read more.
Electron collision cross-sections of c-C4F8 were investigated at low energies by using the R-matrix method. The static exchange (SE), static exchange with polarization (SEP), and close-coupling (CC) models of the R-matrix method were used for the calculation of the scattering cross-section. The shape resonance was detected with all the models at around 3~4 eV, and a Feshbach resonance was detected with the SEP model at 7.73 eV, in good agreement with the previous theoretical calculation. The resonance detected was also associated with the experimental dissociative electron attachment of c-C4F8, which displayed the resonances at the same energy range. The cross-sections calculated are important for plasma modeling and applications. Full article
Show Figures

Figure 1

Article
The Binary-Encounter-Bethe Model for Computation of Singly Differential Cross Sections Due to Electron-Impact Ionization
Atoms 2022, 10(2), 60; https://doi.org/10.3390/atoms10020060 - 06 Jun 2022
Viewed by 362
Abstract
In the present work, we assess the effectiveness of singly differential cross sections (SDCS) due to electron-impact ionization by invoking the binary-encounter-Bethe (BEB) model on various atomic and molecular targets. The computed results were compared with the experimental and theoretical data. A good [...] Read more.
In the present work, we assess the effectiveness of singly differential cross sections (SDCS) due to electron-impact ionization by invoking the binary-encounter-Bethe (BEB) model on various atomic and molecular targets. The computed results were compared with the experimental and theoretical data. A good agreement was observed between the present and the available results. This agreement improves as the incident energy of the projectile increases. The model can be applied to compute the SDCS for the ions produced due to the electron-impact dissociative ionization process and the average energy due to the secondary electrons. Both these quantities are of interest in plasma processing and radiation physics. Full article
Show Figures

Graphical abstract

Article
Impact of Charge Migration and the Angle-Resolved Photoionization Time Delays of the Free and Confined Atom [email protected]60
Atoms 2022, 10(2), 44; https://doi.org/10.3390/atoms10020044 - 30 Apr 2022
Viewed by 642
Abstract
The present study is devoted to isolate and study the effect of charge migration on the photoionization from the [email protected]60. The noble gas atoms, Ar, Kr, and Xe, are confined in the C60 to investigate the impact of charge migration [...] Read more.
The present study is devoted to isolate and study the effect of charge migration on the photoionization from the [email protected]60. The noble gas atoms, Ar, Kr, and Xe, are confined in the C60 to investigate the impact of charge migration from the entrapped atom to the C60 side. The present work concludes that the confinement oscillations in the photoionization features are amplified due to the charge migration. Further, the angle-resolved, spin average time delay is also investigated in the light of confinement. Features in the time delay due to the charge migration are more amplified relative to those in the cross-section or angular distribution. Full article
Show Figures

Figure 1

Article
A Theoretical Study of Scattering of Electrons and Positrons by CO2 Molecule
Atoms 2022, 10(1), 31; https://doi.org/10.3390/atoms10010031 - 09 Mar 2022
Viewed by 891
Abstract
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 [...] Read more.
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. Full article
Show Figures

Figure 1

Article
Elastic and Inelastic Cross Sections for Low-Energy Electron Collisions with ClF Molecule Using the R-Matrix Method
Atoms 2022, 10(1), 8; https://doi.org/10.3390/atoms10010008 - 19 Jan 2022
Viewed by 699
Abstract
The ClF molecule belongs to an interhalogen family and is important in laser physics and condensed phase molecular dynamics. The elastic and excitation scattering cross sections are obtained in a fixed nuclei approximation using the UKRmol+ codes based on R-matrix formalism. The [...] Read more.
The ClF molecule belongs to an interhalogen family and is important in laser physics and condensed phase molecular dynamics. The elastic and excitation scattering cross sections are obtained in a fixed nuclei approximation using the UKRmol+ codes based on R-matrix formalism. The scattering calculations were performed in the static-exchange (SE), static-exchange-plus-polarisation (SEP), and close-coupling (CC) models. Three CC models with different target states were employed, namely, the 1-state, 5-states, and 12-states. In the CC model, the target states were represented by configuration interaction (CI) wavefunctions. A good agreement of dipole and quadrupole moments of the ground state was obtained with the experimental values, which indicates a good representation of the target modelling. The study predicted the existence of a shape resonance in the SE, SEP, and 5-states CC models. This resonance vanished in the 12-states CC model. The excitation cross sections from ground to the lowest two excited states were also reported. The elastic differential and momentum transfer cross sections were obtained in the 12-states CC models. The contribution of long-range interactions to elastic scattering was included via Born closure approach. The quantities like collision frequencies and rate coefficients were also presented over a wide range of electron temperatures. The ionization cross sections were computed using the binary-encounter-Bethe (BEB) model. The results were reported in C2v point group representation. Full article
Show Figures

Figure 1

Planned Papers

The below list represents only planned manuscripts. Some of these manuscripts have not been received by the Editorial Office yet. Papers submitted to MDPI journals are subject to peer-review.

Low energy electron scattering from c-C4F8 

Authorship: Dhanoj Gupta1*, Heechol Choi2, Deuk-Chul Kwon2, Su He3, Mi-Young Song2, Jung-Sik Yoon2 and Jonathan Tennyson3

Department of Physics, School of Advanced Sciences, Vellore Institute of Technology, Vellore, Tamil Nadu 632014, India;

Institute of Plasma Technology, Korea Institute of Fusion Energy, 37 Dongjangsan-ro, Gunsan, Jeollabuk-do 54004, Korea;

Department of Physics and Astronomy, University College London, Gower St., London WCIE 6BT, United Kingdom. *Email: [email protected]

Abstract: Low energy electron impact cross sections of c-C4F8 are investigated using the R-matrix method. The static exchange, static exchange with polarization and configuration interaction models of the R-matrix method are used for the calculation of the scattering cross-section. The shape resonance is detected with all the models at around 3 ~ 4 eV in good comparison with the previous theoretical calculations. The cross sections calculated are important for plasma modelling and applications. 

 

Back to TopTop