Impurity ion flow and temperature measured in a detached divertor with externally applied non-axisymmetric fields on $\mathrm{DIII}$-$\mathrm{D}$

Briesemeister, A. R.; Isler, R. C.; Allen, S. L.; Ahn, J. -W.; McLean, A. G.; Unterberg, E. A.; Hillis, D. L.; Fenstermacher, M. E.; Meyer, W. H.

doi:10.1016/j.jnucmat.2014.11.031

Title: Impurity ion flow and temperature measured in a detached divertor with externally applied non-axisymmetric fields on $$\mathrm{DIII}$$-$$\mathrm{D}$$

Abstract

In this study, externally applied non-axisymmetric magnetic fields are shown to have little effect on the impurity ion flow velocity and temperature as measured by the multichord divertor spectrometer in the DIII-D divertor for both attached and detached conditions. These experiments were performed in H-mode plasmas with the grad-B drift toward the target plates, with and without n = 3 resonant magnetic perturbations (RMPs). The flow velocity in the divertor is shown to change by as much as 30% when deuterium gas puffing is used to create detachment of the divertor plasma. No measurable changes in the C III flow were observed in response to the RMP fields for the conditions used in this work. Images of the C III emission are used along with divertor Thomson scattering to show that the local electron and C III temperatures are equilibrated for the conditions shown.

Authors:

Briesemeister, A. R. ^[1]; Isler, R. C. ^[1]; Allen, S. L. ^[2]; Ahn, J. -W. ^[1]; McLean, A. G. ^[2]; Unterberg, E. A. ^[1]; Hillis, D. L. ^[1]; Fenstermacher, M. E. ^[2]; Meyer, W. H. ^[2]

Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)

Publication Date:: Sat Nov 15 00:00:00 EST 2014

Research Org.:: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Sponsoring Org.:: USDOE Office of Science (SC), Fusion Energy Sciences (FES)

OSTI Identifier:: 1286755

Alternate Identifier(s):: OSTI ID: 1252303; OSTI ID: 1289383

Report Number(s):: LLNL-JRNL-698169
Journal ID: ISSN 0022-3115; AT1010101; ERAT355

Grant/Contract Number:: AC05-00OR22725; FC02-04ER54698; AC52-07NA27344; AC02-00OR22725

Resource Type:: Accepted Manuscript

Journal Name:: Journal of Nuclear Materials

Additional Journal Information:: Journal Volume: 463; Journal Issue: C; Journal ID: ISSN 0022-3115

Publisher:: Elsevier

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; DIII-D; RMP; divertor; 70 PLASMA PHYSICS AND FUSION; plasma flow; spectroscopy; detachment; divertor plasma; divertor diagnostic; carbon-based materials

Citation Formats


                    Briesemeister, A. R., Isler, R. C., Allen, S. L., Ahn, J. -W., McLean, A. G., Unterberg, E. A., Hillis, D. L., Fenstermacher, M. E., and Meyer, W. H. Impurity ion flow and temperature measured in a detached divertor with externally applied non-axisymmetric fields on $\mathrm{DIII}$-$\mathrm{D}$.  United States: N. p., 2014. 
Web.  doi:10.1016/j.jnucmat.2014.11.031.

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                    Briesemeister, A. R., Isler, R. C., Allen, S. L., Ahn, J. -W., McLean, A. G., Unterberg, E. A., Hillis, D. L., Fenstermacher, M. E., & Meyer, W. H. Impurity ion flow and temperature measured in a detached divertor with externally applied non-axisymmetric fields on $\mathrm{DIII}$-$\mathrm{D}$.  United States.  https://doi.org/10.1016/j.jnucmat.2014.11.031

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                    Briesemeister, A. R., Isler, R. C., Allen, S. L., Ahn, J. -W., McLean, A. G., Unterberg, E. A., Hillis, D. L., Fenstermacher, M. E., and Meyer, W. H. Sat .  
"Impurity ion flow and temperature measured in a detached divertor with externally applied non-axisymmetric fields on $\mathrm{DIII}$-$\mathrm{D}$".  United States.  https://doi.org/10.1016/j.jnucmat.2014.11.031.  https://www.osti.gov/servlets/purl/1286755.

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@article{osti_1286755,

  title        = {Impurity ion flow and temperature measured in a detached divertor with externally applied non-axisymmetric fields on $\mathrm{DIII}$-$\mathrm{D}$},

  author       = {Briesemeister, A. R. and Isler, R. C. and Allen, S. L. and Ahn, J. -W. and McLean, A. G. and Unterberg, E. A. and Hillis, D. L. and Fenstermacher, M. E. and Meyer, W. H.},

  abstractNote = {In this study, externally applied non-axisymmetric magnetic fields are shown to have little effect on the impurity ion flow velocity and temperature as measured by the multichord divertor spectrometer in the DIII-D divertor for both attached and detached conditions. These experiments were performed in H-mode plasmas with the grad-B drift toward the target plates, with and without n = 3 resonant magnetic perturbations (RMPs). The flow velocity in the divertor is shown to change by as much as 30% when deuterium gas puffing is used to create detachment of the divertor plasma. No measurable changes in the C III flow were observed in response to the RMP fields for the conditions used in this work. Images of the C III emission are used along with divertor Thomson scattering to show that the local electron and C III temperatures are equilibrated for the conditions shown.},

  doi          = {10.1016/j.jnucmat.2014.11.031},

  journal      = {Journal of Nuclear Materials},

  number       = C,

  volume       = 463,

  place        = {United States},

  year         = {Sat Nov 15 00:00:00 EST 2014},

  month        = {Sat Nov 15 00:00:00 EST 2014}

}

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https://doi.org/10.1016/j.jnucmat.2014.11.031

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Cited by: 1 work

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Figures / Tables:

Fig. 1: (a) The deuterium gas puff used to detach the divertor is shown along with the coil current for one of the (b) lower I-coils used for the shot with RMPs (red dashed lines), but not for the axisymmetric case (blue solid lines). (c) The electron density at themore »

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Works referenced in this record:

Spectroscopic characterization of the DIII-D divertor
journal, February 1997

Isler, R. C.; Wood, R. W.; Klepper, C. C.
Physics of Plasmas, Vol. 4, Issue 2
DOI: 10.1063/1.872095

Characterization of divertor footprints and the pedestal plasmas in the presence of applied n = 3 fields for the attached and detached conditions in NSTX
journal, December 2013

Ahn, J-W; Scotti, F.; Kim, K.
Plasma Physics and Controlled Fusion, Vol. 56, Issue 1
DOI: 10.1088/0741-3335/56/1/015005

Results from radiating divertor experiments with RMP ELM suppression and mitigation
journal, May 2011

Petrie, T. W.; Evans, T. E.; Brooks, N. H.
Nuclear Fusion, Vol. 51, Issue 7
DOI: 10.1088/0029-5515/51/7/073003

Footprint structures due to resonant magnetic perturbations in DIII-D
journal, April 2009

Wingen, A.; Evans, T. E.; Spatschek, K. H.
Physics of Plasmas, Vol. 16, Issue 4
DOI: 10.1063/1.3099053

Comparison between stellarator and tokamak divertor transport
journal, January 2011

Feng, Y.; Kobayashi, M.; Lunt, T.
Plasma Physics and Controlled Fusion, Vol. 53, Issue 2
DOI: 10.1088/0741-3335/53/2/024009

Initial operation of the divertor Thomson scattering diagnostic on DIII-D
journal, February 1997

Carlstrom, T. N.; Hsieh, C. L.; Stockdale, R.
Review of Scientific Instruments, Vol. 68, Issue 2
DOI: 10.1063/1.1147893

Multichord spectroscopy of the DIII‐D divertor region
journal, October 1992

Brooks, N. H.; Howald, A.; Klepper, K.
Review of Scientific Instruments, Vol. 63, Issue 10
DOI: 10.1063/1.1143469

Spectroscopic analysis of normal and reversed ion flows in the DIII-D divertor
journal, February 1999

Isler, R. C.; Brooks, N. H.; West, W. P.
Physics of Plasmas, Vol. 6, Issue 2
DOI: 10.1063/1.873198

A tangentially viewing visible TV system for the DIII-D divertor
journal, January 1997

Fenstermacher, M. E.; Meyer, W. H.; Wood, R. D.
Review of Scientific Instruments, Vol. 68, Issue 1
DOI: 10.1063/1.1147729

Spectroscopic measurements of impurity temperatures and parallel ion flows in the DIII-D divertor
journal, March 1999

Isler, R. C.; Brooks, N. H.; West, W. P.
Journal of Nuclear Materials, Vol. 266-269
DOI: 10.1016/S0022-3115(98)00824-1

Figures / Tables found in this record:

Figures/Tables have been extracted from DOE-funded journal article accepted manuscripts.

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Similar Records

Title: Impurity ion flow and temperature measured in a detached divertor with externally applied non-axisymmetric fields on $$\mathrm{DIII}$$-$$\mathrm{D}$$

Abstract

Citation Formats

Figures / Tables:

Spectroscopic characterization of the DIII-D divertor journal, February 1997

Characterization of divertor footprints and the pedestal plasmas in the presence of applied n = 3 fields for the attached and detached conditions in NSTX journal, December 2013

Results from radiating divertor experiments with RMP ELM suppression and mitigation journal, May 2011

Footprint structures due to resonant magnetic perturbations in DIII-D journal, April 2009

Comparison between stellarator and tokamak divertor transport journal, January 2011

Initial operation of the divertor Thomson scattering diagnostic on DIII-D journal, February 1997

Multichord spectroscopy of the DIII‐D divertor region journal, October 1992

Spectroscopic analysis of normal and reversed ion flows in the DIII-D divertor journal, February 1999

A tangentially viewing visible TV system for the DIII-D divertor journal, January 1997

Spectroscopic measurements of impurity temperatures and parallel ion flows in the DIII-D divertor journal, March 1999

Spectroscopic characterization of the DIII-D divertor
journal, February 1997

Characterization of divertor footprints and the pedestal plasmas in the presence of applied n = 3 fields for the attached and detached conditions in NSTX
journal, December 2013

Results from radiating divertor experiments with RMP ELM suppression and mitigation
journal, May 2011

Footprint structures due to resonant magnetic perturbations in DIII-D
journal, April 2009

Comparison between stellarator and tokamak divertor transport
journal, January 2011

Initial operation of the divertor Thomson scattering diagnostic on DIII-D
journal, February 1997

Multichord spectroscopy of the DIII‐D divertor region
journal, October 1992

Spectroscopic analysis of normal and reversed ion flows in the DIII-D divertor
journal, February 1999

A tangentially viewing visible TV system for the DIII-D divertor
journal, January 1997

Spectroscopic measurements of impurity temperatures and parallel ion flows in the DIII-D divertor
journal, March 1999