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Title: Relativistic R -matrix calculations for the electron-impact excitation of neutral molybdenum

Abstract

A recent PISCES-B Mod experiment [Nishijima et al., J. Phys. B 43, 225701 (2010)] has revealed up to a factor of 5 discrepancy between measurement and the two existing theoretical models [Badnell et al., J. Phys. B 29, 3683 (1996); Bartschat et al., J. Phys. B 35, 2899 (2002)], providing important diagnostics for Mo i. In the following paper we address this issue by employing a relativistic atomic structure and R -matrix scattering calculations to improve upon the available models for future applications and benchmark results against a recent Compact Toroidal Hybrid experiment [Hartwell et al., Fusion Sci. Technol. 72, 76 (2017)]. We determine the atomic structure of Mo i using grasp 0 , which implements the multiconfigurational Dirac-Fock method. Fine structure energies and radiative transition rates are presented and compared to existing experimental and theoretical values. The electron-impact excitation of Mo i is investigated using the relativistic R -matrix method and the parallel versions of the Dirac atomic R -matrix codes. Electron-impact excitation cross sections are presented and compared to the few available theoretical cross sections. Throughout, our emphasis is on improving the results for the z 5 P o 1 , 2 , 3 → a 5 Smore » 2 , z 7 P o 2 , 3 , 4 → a 7 S 3 and y 7 P o 2 , 3 , 4 → a 7 S 3 electric dipole transitions of particular relevance for diagnostic work.« less

Authors:
 [1];  [2];  [2];  [2];  [1];  [1]
  1. Queen's Univ., Belfast, Northern Ireland (United Kingdom). School of Mathematics and Physics
  2. Auburn Univ., AL (United States). Dept. of Physics
Publication Date:
Research Org.:
Lawrence Berkeley National Laboratory-National Energy Research Scientific Computing Center
Sponsoring Org.:
USDOE
OSTI Identifier:
1523836
Resource Type:
Journal Article
Journal Name:
Physical Review A
Additional Journal Information:
Journal Volume: 96; Journal Issue: 4; Journal ID: ISSN 2469-9926
Country of Publication:
United States
Language:
English

Citation Formats

Smyth, R. T., Johnson, C. A., Ennis, D. A., Loch, S. D., Ramsbottom, C. A., and Ballance, C. P. Relativistic R -matrix calculations for the electron-impact excitation of neutral molybdenum. United States: N. p., 2017. Web. doi:10.1103/PhysRevA.96.042713.
Smyth, R. T., Johnson, C. A., Ennis, D. A., Loch, S. D., Ramsbottom, C. A., & Ballance, C. P. Relativistic R -matrix calculations for the electron-impact excitation of neutral molybdenum. United States. doi:10.1103/PhysRevA.96.042713.
Smyth, R. T., Johnson, C. A., Ennis, D. A., Loch, S. D., Ramsbottom, C. A., and Ballance, C. P. Sun . "Relativistic R -matrix calculations for the electron-impact excitation of neutral molybdenum". United States. doi:10.1103/PhysRevA.96.042713.
@article{osti_1523836,
title = {Relativistic R -matrix calculations for the electron-impact excitation of neutral molybdenum},
author = {Smyth, R. T. and Johnson, C. A. and Ennis, D. A. and Loch, S. D. and Ramsbottom, C. A. and Ballance, C. P.},
abstractNote = {A recent PISCES-B Mod experiment [Nishijima et al., J. Phys. B 43, 225701 (2010)] has revealed up to a factor of 5 discrepancy between measurement and the two existing theoretical models [Badnell et al., J. Phys. B 29, 3683 (1996); Bartschat et al., J. Phys. B 35, 2899 (2002)], providing important diagnostics for Mo i. In the following paper we address this issue by employing a relativistic atomic structure and R -matrix scattering calculations to improve upon the available models for future applications and benchmark results against a recent Compact Toroidal Hybrid experiment [Hartwell et al., Fusion Sci. Technol. 72, 76 (2017)]. We determine the atomic structure of Mo i using grasp 0 , which implements the multiconfigurational Dirac-Fock method. Fine structure energies and radiative transition rates are presented and compared to existing experimental and theoretical values. The electron-impact excitation of Mo i is investigated using the relativistic R -matrix method and the parallel versions of the Dirac atomic R -matrix codes. Electron-impact excitation cross sections are presented and compared to the few available theoretical cross sections. Throughout, our emphasis is on improving the results for the z 5 P o 1 , 2 , 3 → a 5 S 2 , z 7 P o 2 , 3 , 4 → a 7 S 3 and y 7 P o 2 , 3 , 4 → a 7 S 3 electric dipole transitions of particular relevance for diagnostic work.},
doi = {10.1103/PhysRevA.96.042713},
journal = {Physical Review A},
issn = {2469-9926},
number = 4,
volume = 96,
place = {United States},
year = {2017},
month = {10}
}

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