### Abstract

Language | English |
---|---|

Pages | 055202 |

Number of pages | 17 |

Journal | Journal of Physics B: Atomic, Molecular and Optical Physics |

Volume | 46 |

Issue number | 5 |

DOIs | |

Publication status | Published - 19 Feb 2013 |

Externally published | Yes |

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### Cite this

*Journal of Physics B: Atomic, Molecular and Optical Physics*,

*46*(5), 055202. https://doi.org/10.1088/0953-4075/46/5/055202

}

*Journal of Physics B: Atomic, Molecular and Optical Physics*, vol. 46, no. 5, pp. 055202. https://doi.org/10.1088/0953-4075/46/5/055202

**Electron-impact excitation and ionization of W 3+ for the determination of tungsten influx in a fusion plasma.** / Ballance, C P; Loch, S D; Pindzola, M S; Griffin, D C.

Research output: Contribution to journal › Article

TY - JOUR

T1 - Electron-impact excitation and ionization of W 3+ for the determination of tungsten influx in a fusion plasma

AU - Ballance, C P

AU - Loch, S D

AU - Pindzola, M S

AU - Griffin, D C

PY - 2013/2/19

Y1 - 2013/2/19

N2 - Tungsten will be employed as a plasma facing material in the ITER fusion reactor under construction in Cadarache, France; therefore, there is a significant need for accurate electron-impact excitation and ionization data for the ions of tungsten. We report on the results of extensive calculations of ionization and excitation for W 3+ that are intended to provide the atomic data needed for the determination of impurity influx diagnostics of tungsten in several existing tokamak reactors. The electron-impact excitation rate coefficients for this study were determined using the relativistic R -matrix method. The contribution to direct electron-impact ionization was determined using the distorted-wave approximation, the accuracy of which was verified by an R -matrix with pseudo states calculation. Contributions to total ionization from excitation autoionization were also generated from the relativistic R -matrix method. These results were then employed to calculate values of ionization per emitted photon, or SXB ratios, for four carefully selected spectral lines; these data will allow the determination of impurity influx from tungsten facing surfaces. For the range of densities of importance in the edge region of a tokamak reactor, these SXB ratios are found to be nearly independent of electron density but vary significantly with electron temperature.

AB - Tungsten will be employed as a plasma facing material in the ITER fusion reactor under construction in Cadarache, France; therefore, there is a significant need for accurate electron-impact excitation and ionization data for the ions of tungsten. We report on the results of extensive calculations of ionization and excitation for W 3+ that are intended to provide the atomic data needed for the determination of impurity influx diagnostics of tungsten in several existing tokamak reactors. The electron-impact excitation rate coefficients for this study were determined using the relativistic R -matrix method. The contribution to direct electron-impact ionization was determined using the distorted-wave approximation, the accuracy of which was verified by an R -matrix with pseudo states calculation. Contributions to total ionization from excitation autoionization were also generated from the relativistic R -matrix method. These results were then employed to calculate values of ionization per emitted photon, or SXB ratios, for four carefully selected spectral lines; these data will allow the determination of impurity influx from tungsten facing surfaces. For the range of densities of importance in the edge region of a tokamak reactor, these SXB ratios are found to be nearly independent of electron density but vary significantly with electron temperature.

U2 - 10.1088/0953-4075/46/5/055202

DO - 10.1088/0953-4075/46/5/055202

M3 - Article

VL - 46

SP - 055202

JO - Journal of Physics B: Atomic Molecular and Optical Physics

T2 - Journal of Physics B: Atomic Molecular and Optical Physics

JF - Journal of Physics B: Atomic Molecular and Optical Physics

SN - 0953-4075

IS - 5

ER -