Modification of the electron energy distribution function during lithium experiments on the National Spherical Torus Experiment

M. A. Jaworski; M. G. Bell; T. K. Gray; R. Kaita; J. Kallman; H. W. Kugel; B. Leblanc; A. G. McLean; S. A. Sabbagh; V. A. Soukhanovskii; D. P. Stotler; V. Surla

doi:10.1016/j.fusengdes.2011.07.013

Modification of the electron energy distribution function during lithium experiments on the National Spherical Torus Experiment

M. A. Jaworski, M. G. Bell, T. K. Gray, R. Kaita, J. Kallman, H. W. Kugel, B. Leblanc, A. G. McLean, S. A. Sabbagh, V. A. Soukhanovskii, D. P. Stotler, V. Surla

Power Exhaust and Particle Control

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

24 Scopus citations

Abstract

The National Spherical Torus Experiment (NSTX) has recently studied the use of a liquid lithium divertor (LLD). Divertor Langmuir probes have also been installed for making measurements of the local plasma conditions. A non-local probe interpretation method is used to supplement the classical probe interpretation and obtain measurements of the electron energy distribution function (EEDF) which show the occurrence of a hot-electron component. Analysis is made of two discharges within a sequence that exhibited changes in plasma fueling efficiency. It is found that the local electron temperature increases and that this increase is most strongly correlated with the energy contained within the hot-electron population. Preliminary interpretative modeling indicates that kinetic effects are likely in the NSTX scrape-off layer (SOL) plasma. The decrease in plasma fueling efficiency, increase in local temperature, and increase in hot-electron fraction are all consistent with an absorbing surface intercepting the SOL plasma.

Original language	English
Pages (from-to)	1711-1718
Number of pages	8
Journal	Fusion Engineering and Design
Volume	87
Issue number	10
DOIs	https://doi.org/10.1016/j.fusengdes.2011.07.013
State	Published - Oct 2012

Funding

The authors would like to thank Y. Raitses for many useful discussions regarding the Langmuir probe interpretation and E. Spence for discussions on data analysis and reduction methods. This work is supported under Department of Energy contract No. DE-AC02-09CHI1466.

Funders	Funder number
U.S. Department of Energy

Keywords

Electron distribution function
Langmuir probe
Lithium plasma-facing component

UN SDGs

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

Access to Document

10.1016/j.fusengdes.2011.07.013

Cite this

Jaworski, M. A., Bell, M. G., Gray, T. K., Kaita, R., Kallman, J., Kugel, H. W., Leblanc, B., McLean, A. G., Sabbagh, S. A., Soukhanovskii, V. A., Stotler, D. P., & Surla, V. (2012). Modification of the electron energy distribution function during lithium experiments on the National Spherical Torus Experiment. Fusion Engineering and Design, 87(10), 1711-1718. https://doi.org/10.1016/j.fusengdes.2011.07.013

@article{9bb0f88ca392400b9beed0cea86d8483,

title = "Modification of the electron energy distribution function during lithium experiments on the National Spherical Torus Experiment",

abstract = "The National Spherical Torus Experiment (NSTX) has recently studied the use of a liquid lithium divertor (LLD). Divertor Langmuir probes have also been installed for making measurements of the local plasma conditions. A non-local probe interpretation method is used to supplement the classical probe interpretation and obtain measurements of the electron energy distribution function (EEDF) which show the occurrence of a hot-electron component. Analysis is made of two discharges within a sequence that exhibited changes in plasma fueling efficiency. It is found that the local electron temperature increases and that this increase is most strongly correlated with the energy contained within the hot-electron population. Preliminary interpretative modeling indicates that kinetic effects are likely in the NSTX scrape-off layer (SOL) plasma. The decrease in plasma fueling efficiency, increase in local temperature, and increase in hot-electron fraction are all consistent with an absorbing surface intercepting the SOL plasma.",

keywords = "Electron distribution function, Langmuir probe, Lithium plasma-facing component",

author = "Jaworski, {M. A.} and Bell, {M. G.} and Gray, {T. K.} and R. Kaita and J. Kallman and Kugel, {H. W.} and B. Leblanc and McLean, {A. G.} and Sabbagh, {S. A.} and Soukhanovskii, {V. A.} and Stotler, {D. P.} and V. Surla",

year = "2012",

month = oct,

doi = "10.1016/j.fusengdes.2011.07.013",

language = "English",

volume = "87",

pages = "1711--1718",

journal = "Fusion Engineering and Design",

issn = "0920-3796",

publisher = "Elsevier",

number = "10",

}

Jaworski, MA, Bell, MG, Gray, TK, Kaita, R, Kallman, J, Kugel, HW, Leblanc, B, McLean, AG, Sabbagh, SA, Soukhanovskii, VA, Stotler, DP & Surla, V 2012, 'Modification of the electron energy distribution function during lithium experiments on the National Spherical Torus Experiment', Fusion Engineering and Design, vol. 87, no. 10, pp. 1711-1718. https://doi.org/10.1016/j.fusengdes.2011.07.013

TY - JOUR

T1 - Modification of the electron energy distribution function during lithium experiments on the National Spherical Torus Experiment

AU - Jaworski, M. A.

AU - Bell, M. G.

AU - Gray, T. K.

AU - Kaita, R.

AU - Kallman, J.

AU - Kugel, H. W.

AU - Leblanc, B.

AU - McLean, A. G.

AU - Sabbagh, S. A.

AU - Soukhanovskii, V. A.

AU - Stotler, D. P.

AU - Surla, V.

PY - 2012/10

Y1 - 2012/10

N2 - The National Spherical Torus Experiment (NSTX) has recently studied the use of a liquid lithium divertor (LLD). Divertor Langmuir probes have also been installed for making measurements of the local plasma conditions. A non-local probe interpretation method is used to supplement the classical probe interpretation and obtain measurements of the electron energy distribution function (EEDF) which show the occurrence of a hot-electron component. Analysis is made of two discharges within a sequence that exhibited changes in plasma fueling efficiency. It is found that the local electron temperature increases and that this increase is most strongly correlated with the energy contained within the hot-electron population. Preliminary interpretative modeling indicates that kinetic effects are likely in the NSTX scrape-off layer (SOL) plasma. The decrease in plasma fueling efficiency, increase in local temperature, and increase in hot-electron fraction are all consistent with an absorbing surface intercepting the SOL plasma.

AB - The National Spherical Torus Experiment (NSTX) has recently studied the use of a liquid lithium divertor (LLD). Divertor Langmuir probes have also been installed for making measurements of the local plasma conditions. A non-local probe interpretation method is used to supplement the classical probe interpretation and obtain measurements of the electron energy distribution function (EEDF) which show the occurrence of a hot-electron component. Analysis is made of two discharges within a sequence that exhibited changes in plasma fueling efficiency. It is found that the local electron temperature increases and that this increase is most strongly correlated with the energy contained within the hot-electron population. Preliminary interpretative modeling indicates that kinetic effects are likely in the NSTX scrape-off layer (SOL) plasma. The decrease in plasma fueling efficiency, increase in local temperature, and increase in hot-electron fraction are all consistent with an absorbing surface intercepting the SOL plasma.

KW - Electron distribution function

KW - Langmuir probe

KW - Lithium plasma-facing component

UR - http://www.scopus.com/inward/record.url?scp=84867020264&partnerID=8YFLogxK

U2 - 10.1016/j.fusengdes.2011.07.013

DO - 10.1016/j.fusengdes.2011.07.013

M3 - Article

AN - SCOPUS:84867020264

SN - 0920-3796

VL - 87

SP - 1711

EP - 1718

JO - Fusion Engineering and Design

JF - Fusion Engineering and Design

IS - 10

ER -

Modification of the electron energy distribution function during lithium experiments on the National Spherical Torus Experiment

Abstract

Funding

Keywords

UN SDGs

Access to Document

Other files and links

Fingerprint

Cite this