English
Related papers

Related papers: Simple electron-impact excitation cross-sections i…

200 papers

Every observation of astrophysical objects involving a spectrum requires atomic data for the interpretation of line fluxes, line ratios and ionization state of the emitting plasma. One of the processes which determines it is collisional…

High Energy Astrophysical Phenomena · Physics 2017-05-10 I. Urdampilleta , J. S. Kaastra , M. Mehdipour

Emission lines from highly-excited states (n >= 5) of H- and He-like ions have been detected in astrophysical sources and fusion plasmas. For such excited states, R-matrix or distorted wave calculations for electron-impact excitation are…

Instrumentation and Methods for Astrophysics · Physics 2016-08-17 L. Fernandez-Menchero , G. Del Zanna , N. R. Badnell

We report a detailed study of features of electron-impact excitation (EIE) of Ca IV for the first time using the relativistic Breit-Pauli R-Matrix method with a large close coupling wavefunction expansion of 54 fine structure levels…

Solar and Stellar Astrophysics · Physics 2023-04-05 Sultana Nahar , Bilal Shafique

We calculate the cross-section of ionization by free-electron impacts in high or moderate density plasmas. We show that the so-called ionization potential depression (IPD) strongly affects the magnitude of the cross-section in the…

Atomic Physics · Physics 2023-09-14 Djamel Benredjem , Jean-Christophe Pain , Annette Calisti , Sandrine Ferri

Collisions between electrons and radiating atoms broaden spectral absorption and emission lines in dense plasmas. High densities also introduce screening and pressure ionization effects that distort the wavefunctions of both bound and free…

Plasma Physics · Physics 2026-02-26 Julian P. Kinney , Stephanie B. Hansen , Thomas A. Gomez , Scott D. Baalrud

Motional Stark effect (MSE) spectroscopy represents a unique diagnostic tool capable of determining the magnitude of the magnetic field and its direction in the core of fusion plasmas. The primary excitation channel for fast hydrogen atoms…

Atomic Physics · Physics 2020-03-06 Oleksandr Marchuk , David R. Schultz , Yuri Ralchenko

The Coulomb logarithm often enters various plasma models and simulation methods for computing the transport and relaxation properties of plasmas. Traditionally, a classical pair collision picture was used to calculate the Coulomb logarithm…

Plasma Physics · Physics 2024-08-20 S. K. Kodanova , T. S. Ramazanov , M. K. Issanova

We use the recently introduced independent-atom-model pixel counting method to calculate proton-impact net ionization cross sections for a large class of biologically relevant systems including pyrimidines, purines, amino acids, and…

Atomic and Molecular Clusters · Physics 2019-10-02 Hans Jürgen Lüdde , Marko Horbatsch , Tom Kirchner

A comprehensive study of relativistic and resonance effects in electron impact excitation of (e+Fe XVII) is carried out using the BPRM method in the relativistic close coupling approximation. Two sets of eigenfunction expansions are…

Astrophysics · Physics 2009-11-07 Guo-Xin Chen , Anil K. Pradhan , W. Eissner

The primary X-ray diagnostic lines in He-like ions are mainly excited by electron impact from the ground level to the n = 2 levels, but at high temperatures n > 2 levels are also excited. In order to describe the atomic processes more…

Astrophysics · Physics 2009-11-07 Franck Delahaye , Anil K. Pradhan

In this paper, the ionization and recombination coefficients of dense semiclassical hydrogen plasma on the basis of the effective interaction potential have been investigated. For this goal the Bohr$-$Lindhard method and method phase…

Collision strengths for electron-impact of fine-structure level excitation within the ground term of Ne$^{+}$ and Ne$^{2+}$ are calculated using the Breit-Pauli, Intermediate Coupling Frame Transformation, and DARC $R$-matrix methods.…

Atomic Physics · Physics 2017-05-31 Qianxia Wang , S. D. Loch , Y. Li , M. S. Pindzola , R. Cumbee , P. Stancil , B. McLaughlin , C. P. Ballance

Rate coefficients for photorecombination (PR) and cross sections for electron-impact ionization (EII) of Fe$^{14+}$ forming Fe$^{13+}$ and Fe$^{15+}$, respectively, have been measured by employing the electron-ion merged-beams technique at…

Electron vortex beams (EVB, also known as twisted electron beams) possess an intrinsic orbital angular momentum (OAM) with respect to their propagation direction. This intrinsic OAM represents a new degree of freedom that provides new…

Atomic Physics · Physics 2023-03-07 Nikita Dhankhar , Neha , R. Choubisa

The predictive capability of a plasma discharge model depends on accurate representations of electron-impact collision cross sections, which determine the key reaction rates and transport properties of the plasma. Although many cross…

Plasma Physics · Physics 2024-10-14 Seung Whan Chung , Todd A. Oliver , Laxminarayan L. Raja , Robert D. Moser

The interplay of kinetic electron physics and atomic processes in ultrashort laser-plasma interactions provides a comprehensive understanding of electron energy distribution's impact on plasma properties. Notably, non-equilibrium electrons…

Plasma Physics · Physics 2024-03-27 M. S. Cho , H. -K. Chung , M. E. Foord , S. B. Libby , B. I. Cho

Spectral lines emitted by plasmas provide information about the thermodynamic conditions, the degree of randomness or the interactions prevailing in the medium. Collisions by plasma electrons penetrating the extent of bound-electron…

Atomic Physics · Physics 2019-05-22 Jean-Christophe Pain , Franck Gilleron

Cross-sections for dissociative recombination and electron-impact vibrational excitation of the BF$^+_2$ molecular ion are computed using a theoretical approach that combines the normal modes approximation for the vibrational states of the…

Plasma Physics · Physics 2024-05-03 V. Kokoouline , M. Ayouz , J. Zs. Mezei , K. Hassouni , I. F. Schneider

Differential cross sections for the electro-disintegration process $e + {^4He} \longrightarrow {^3H}+ p + e'$ are calculated, using a model in which the final state interaction is included by means of a nucleon-nucleus (3+1) potential…

Nuclear Theory · Physics 2009-10-31 M Braun , L L Howell , S A Sofianos , W Sandhas

Energy levels and transition rates for electric-dipole, electric-quadrupole, electric-octupole, magnetic-dipole, and magnetic-quadrupole transitions among the levels arising from the $n\ \leq$ 5 configurations in B-like Kr XXXII are…

Atomic Physics · Physics 2020-05-20 Yanting Li , Ra Si , Jinqing Li , Chunyu Zhang , Ke Yao , Kai Wang , Mingfeng Gu , Chongyang Chen