Measurement of the passive fast-ion D-alpha emission on the NSTX-U tokamak

doi:10.1088/1361-6587/aa9fde

Title: Measurement of the passive fast-ion D-alpha emission on the NSTX-U tokamak

Abstract

On National Spherical Torus Experiment Upgrade, the passive fast-ion D-alpha (passive-FIDA) spectra from charge exchange (CX) between the beam ions and the background neutrals are measured and simulated. The results indicate that the passive-FIDA signal is measurable and comparable to the active-FIDA on several channels, such as at the major radius R = 117 cm. For this, active-FIDA means the active D-alpha emission from the fast ions that CX with the injected neutrals. The shapes of measured spectra are in agreement with FIDASIM simulations on many fibers. Furthermore, the passive-FIDA spatial profile agrees with the simulation. When making measurements of active-FIDA in the edge region using time-slice subtraction, variations in the passive-FIDA contribution to the signal should be considered.

Authors:

^[1]; Heidbrink, W. W. ^[1];

^[1];

^[2]; Stagner, L. ^[1]; Bell, R. E. ^[2];

^[2]; Scotti, F. ^[3]

Univ. of California, Irvine, CA (United States)
Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Publication Date:: 2018-01-08

Research Org.:: Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Sponsoring Org.:: USDOE

OSTI Identifier:: 1432936

Grant/Contract Number:: AC02-09CH11466; FG02-06ER54867; FG03-02ER54681

Resource Type:: Journal Article: Accepted Manuscript

Journal Name:: Plasma Physics and Controlled Fusion

Additional Journal Information:: Journal Volume: 60; Journal Issue: 2; Journal ID: ISSN 0741-3335

Publisher:: IOP Science

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY

Citation Formats


                    Hao, G. Z., Heidbrink, W. W., Liu, D., Podesta, M., Stagner, L., Bell, R. E., Bortolon, A., and Scotti, F. Measurement of the passive fast-ion D-alpha emission on the NSTX-U tokamak.  United States: N. p., 2018. 
        Web.  doi:10.1088/1361-6587/aa9fde.

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                    Hao, G. Z., Heidbrink, W. W., Liu, D., Podesta, M., Stagner, L., Bell, R. E., Bortolon, A., & Scotti, F. Measurement of the passive fast-ion D-alpha emission on the NSTX-U tokamak.  United States.  doi:10.1088/1361-6587/aa9fde.

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                    Hao, G. Z., Heidbrink, W. W., Liu, D., Podesta, M., Stagner, L., Bell, R. E., Bortolon, A., and Scotti, F. Mon .  
        "Measurement of the passive fast-ion D-alpha emission on the NSTX-U tokamak".  United States.  doi:10.1088/1361-6587/aa9fde.  https://www.osti.gov/servlets/purl/1432936.

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@article{osti_1432936,

  title        = {Measurement of the passive fast-ion D-alpha emission on the NSTX-U tokamak},

  author       = {Hao, G. Z. and Heidbrink, W. W. and Liu, D. and Podesta, M. and Stagner, L. and Bell, R. E. and Bortolon, A. and Scotti, F.},

  abstractNote = {On National Spherical Torus Experiment Upgrade, the passive fast-ion D-alpha (passive-FIDA) spectra from charge exchange (CX) between the beam ions and the background neutrals are measured and simulated. The results indicate that the passive-FIDA signal is measurable and comparable to the active-FIDA on several channels, such as at the major radius R = 117 cm. For this, active-FIDA means the active D-alpha emission from the fast ions that CX with the injected neutrals. The shapes of measured spectra are in agreement with FIDASIM simulations on many fibers. Furthermore, the passive-FIDA spatial profile agrees with the simulation. When making measurements of active-FIDA in the edge region using time-slice subtraction, variations in the passive-FIDA contribution to the signal should be considered.},

  doi          = {10.1088/1361-6587/aa9fde},

  journal      = {Plasma Physics and Controlled Fusion},

  issn         = {0741-3335},

  number       = 2,

  volume       = 60,

  place        = {United States},

  year         = {2018},

  month        = {1}

}

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DOI: 10.1088/1361-6587/aa9fde

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Figures / Tables:

Figure 1: Time evolution of (a) plasma current, (b) injected beam power, (c) lineaveraged electron density at inner (117 cm) and outer (140 cm) chords, and (d) electron temperature. Here, 117 and 140 cm correspond to flux surface √ ψ_p = 0.43 and 0.87, respectively, with ψ_p being normalized poloidalmore »

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