The effect of metastable atomic levels in neutral tungsten for erosion and impurity transport applications

C. A. Johnson; S. D. Loch; D. A. Ennis

doi:10.1088/1361-6587/abc08b

The effect of metastable atomic levels in neutral tungsten for erosion and impurity transport applications

C. A. Johnson, S. D. Loch, D. A. Ennis

Research output: Contribution to journal › Article › peer-review

12 Scopus citations

Abstract

Long-lived metastable states in neutral tungsten are shown to potentially impact measurements of tungsten erosion from plasma facing components. Time-dependent collisional radiative modeling of neutral tungsten is used to analyze the role of these states in tungsten emission and ionization. The large number of non-quasistatic atomic states in neutral tungsten can take on the order of milliseconds to reach equilibrium, depending on plasma conditions, causing erosion measurements to be affected by the metastable populations. Previous measurements using the 400.88 nm tungsten emission line could be affected by these non-quasistatic metastable effects. Therefore, a scheme for measuring the relative metastable fractions is proposed through simultaneous observation of multiple ultraviolet spectral lines of neutral W. The accuracy of gross erosion measurements could potentially be increased by inclusion of these previously unconsidered metastable effects.

Original language	English
Article number	125017
Journal	Plasma Physics and Controlled Fusion
Volume	62
Issue number	12
DOIs	https://doi.org/10.1088/1361-6587/abc08b
State	Published - Oct 2020
Externally published	Yes

Keywords

Collisional radiative modeling
ColRadPy
Erosion
Metastable state
S/XB
Spectroscopy
Tungsten

UN SDGs

This output contributes to the following UN Sustainable Development Goals (SDGs)

Access to Document

10.1088/1361-6587/abc08b

Cite this

@article{b7c424868d8f45d0bf940a27371101a5,

title = "The effect of metastable atomic levels in neutral tungsten for erosion and impurity transport applications",

abstract = "Long-lived metastable states in neutral tungsten are shown to potentially impact measurements of tungsten erosion from plasma facing components. Time-dependent collisional radiative modeling of neutral tungsten is used to analyze the role of these states in tungsten emission and ionization. The large number of non-quasistatic atomic states in neutral tungsten can take on the order of milliseconds to reach equilibrium, depending on plasma conditions, causing erosion measurements to be affected by the metastable populations. Previous measurements using the 400.88 nm tungsten emission line could be affected by these non-quasistatic metastable effects. Therefore, a scheme for measuring the relative metastable fractions is proposed through simultaneous observation of multiple ultraviolet spectral lines of neutral W. The accuracy of gross erosion measurements could potentially be increased by inclusion of these previously unconsidered metastable effects.",

keywords = "Collisional radiative modeling, ColRadPy, Erosion, Metastable state, S/XB, Spectroscopy, Tungsten",

author = "Johnson, {C. A.} and Loch, {S. D.} and Ennis, {D. A.}",

note = "Publisher Copyright: {\textcopyright} 2020 IOP Publishing Ltd Printed in the UK",

year = "2020",

month = oct,

doi = "10.1088/1361-6587/abc08b",

language = "English",

volume = "62",

journal = "Plasma Physics and Controlled Fusion",

issn = "0741-3335",

publisher = "IOP Publishing",

number = "12",

}

TY - JOUR

T1 - The effect of metastable atomic levels in neutral tungsten for erosion and impurity transport applications

AU - Johnson, C. A.

AU - Loch, S. D.

AU - Ennis, D. A.

PY - 2020/10

Y1 - 2020/10

N2 - Long-lived metastable states in neutral tungsten are shown to potentially impact measurements of tungsten erosion from plasma facing components. Time-dependent collisional radiative modeling of neutral tungsten is used to analyze the role of these states in tungsten emission and ionization. The large number of non-quasistatic atomic states in neutral tungsten can take on the order of milliseconds to reach equilibrium, depending on plasma conditions, causing erosion measurements to be affected by the metastable populations. Previous measurements using the 400.88 nm tungsten emission line could be affected by these non-quasistatic metastable effects. Therefore, a scheme for measuring the relative metastable fractions is proposed through simultaneous observation of multiple ultraviolet spectral lines of neutral W. The accuracy of gross erosion measurements could potentially be increased by inclusion of these previously unconsidered metastable effects.

AB - Long-lived metastable states in neutral tungsten are shown to potentially impact measurements of tungsten erosion from plasma facing components. Time-dependent collisional radiative modeling of neutral tungsten is used to analyze the role of these states in tungsten emission and ionization. The large number of non-quasistatic atomic states in neutral tungsten can take on the order of milliseconds to reach equilibrium, depending on plasma conditions, causing erosion measurements to be affected by the metastable populations. Previous measurements using the 400.88 nm tungsten emission line could be affected by these non-quasistatic metastable effects. Therefore, a scheme for measuring the relative metastable fractions is proposed through simultaneous observation of multiple ultraviolet spectral lines of neutral W. The accuracy of gross erosion measurements could potentially be increased by inclusion of these previously unconsidered metastable effects.

KW - Collisional radiative modeling

KW - ColRadPy

KW - Erosion

KW - Metastable state

KW - S/XB

KW - Spectroscopy

KW - Tungsten

UR - http://www.scopus.com/inward/record.url?scp=85095805429&partnerID=8YFLogxK

U2 - 10.1088/1361-6587/abc08b

DO - 10.1088/1361-6587/abc08b

M3 - Article

AN - SCOPUS:85095805429

SN - 0741-3335

VL - 62

JO - Plasma Physics and Controlled Fusion

JF - Plasma Physics and Controlled Fusion

IS - 12

M1 - 125017

ER -

The effect of metastable atomic levels in neutral tungsten for erosion and impurity transport applications

Abstract

Keywords

UN SDGs

Access to Document

Other files and links

Fingerprint

Cite this