Synthetic diagnostic for assessing spatial averaging of charge exchange recombination spectroscopy measurements
Abstract
A synthetic charge exchange recombination spectroscopy diagnostic based on the FIDASIM modeling suite has been created for the DIII-D tokamak. This synthetic diagnostic assumes that the ions have Maxwellian distribution functions on each flux surface and models emission from charge exchange events between the beam neutrals and a fully ionized impurity. This work was motivated by the observation of non-Gaussian spectra that may be caused by spatial averaging, atomic physics, or non-Maxwellian distribution functions. Measurements of non-Gaussian spectra commonly observed in the high confinement mode pedestal and in plasmas with large core gradients are compared to the synthetic diagnostic. Spatial averaging alone cannot account for the observations in these two cases, opening up the possibility of there being other causes such as non-Maxwellian distribution functions. Here, the synthetic diagnostic has also been used to resolve a long-standing issue: it is shown that the lower temperatures measured by using vertical view chords relative to tangential view chords are due to increased spatial averaging for vertical views due to the DIII-D neutral beams being approximately twice as tall as they are wide.
- Authors:
-
[1];
[2];
[3];
[1];
- General Atomics, San Diego, CA (United States)
- Univ. of California, Davis, CA (United States)
- Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
- Publication Date:
- Research Org.:
- General Atomics, San Diego, CA (United States); Princeton Univ., NJ (United States)
- Sponsoring Org.:
- USDOE Office of Science (SC), Fusion Energy Sciences (FES)
- OSTI Identifier:
- 1609187
- Alternate Identifier(s):
- OSTI ID: 1459475
- Grant/Contract Number:
- FC02-04ER54698; AC02-09CH11466
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Review of Scientific Instruments
- Additional Journal Information:
- Journal Volume: 89; Journal Issue: 10; Journal ID: ISSN 0034-6748
- Publisher:
- American Institute of Physics (AIP)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; instruments & instrumentation; physics
Citation Formats
Chrystal, C., Sulyman, A. A., Haskey, S. R., Burrell, K. H., and Grierson, B. A. Synthetic diagnostic for assessing spatial averaging of charge exchange recombination spectroscopy measurements. United States: N. p., 2018.
Web. doi:10.1063/1.5036964.
Chrystal, C., Sulyman, A. A., Haskey, S. R., Burrell, K. H., & Grierson, B. A. Synthetic diagnostic for assessing spatial averaging of charge exchange recombination spectroscopy measurements. United States. https://doi.org/10.1063/1.5036964
Chrystal, C., Sulyman, A. A., Haskey, S. R., Burrell, K. H., and Grierson, B. A. Mon .
"Synthetic diagnostic for assessing spatial averaging of charge exchange recombination spectroscopy measurements". United States. https://doi.org/10.1063/1.5036964. https://www.osti.gov/servlets/purl/1609187.
@article{osti_1609187,
title = {Synthetic diagnostic for assessing spatial averaging of charge exchange recombination spectroscopy measurements},
author = {Chrystal, C. and Sulyman, A. A. and Haskey, S. R. and Burrell, K. H. and Grierson, B. A.},
abstractNote = {A synthetic charge exchange recombination spectroscopy diagnostic based on the FIDASIM modeling suite has been created for the DIII-D tokamak. This synthetic diagnostic assumes that the ions have Maxwellian distribution functions on each flux surface and models emission from charge exchange events between the beam neutrals and a fully ionized impurity. This work was motivated by the observation of non-Gaussian spectra that may be caused by spatial averaging, atomic physics, or non-Maxwellian distribution functions. Measurements of non-Gaussian spectra commonly observed in the high confinement mode pedestal and in plasmas with large core gradients are compared to the synthetic diagnostic. Spatial averaging alone cannot account for the observations in these two cases, opening up the possibility of there being other causes such as non-Maxwellian distribution functions. Here, the synthetic diagnostic has also been used to resolve a long-standing issue: it is shown that the lower temperatures measured by using vertical view chords relative to tangential view chords are due to increased spatial averaging for vertical views due to the DIII-D neutral beams being approximately twice as tall as they are wide.},
doi = {10.1063/1.5036964},
journal = {Review of Scientific Instruments},
number = 10,
volume = 89,
place = {United States},
year = {Mon Jul 09 00:00:00 EDT 2018},
month = {Mon Jul 09 00:00:00 EDT 2018}
}
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Works referenced in this record:
Integrated modeling applications for tokamak experiments with OMFIT
journal, July 2015
- Meneghini, O.; Smith, S. P.; Lao, L. L.
- Nuclear Fusion, Vol. 55, Issue 8
Corrections to charge exchange spectroscopic measurements in TFTR due to energy‐dependent excitation rates
journal, August 1988
- Howell, R. B.; Fonck, R. J.; Knize, R. J.
- Review of Scientific Instruments, Vol. 59, Issue 8
An overview of charge-exchange spectroscopy as a plasma diagnostic
journal, February 1994
- Isler, R. C.
- Plasma Physics and Controlled Fusion, Vol. 36, Issue 2
New understanding of poloidal rotation measurements in a Tokamak plasma
conference, January 2000
- Bell, R. E.
- The 12th topical conference on atomic processes in plasmas, AIP Conference Proceedings
Extraction of poloidal velocity from charge exchange recombination spectroscopy measurements
journal, October 2004
- Solomon, W. M.; Burrell, K. H.; Gohil, P.
- Review of Scientific Instruments, Vol. 75, Issue 10
Kinetic theory and atomic physics corrections for determination of ion velocities from charge-exchange spectroscopy
journal, August 2013
- Muñoz Burgos, J. M.; Burrell, K. H.; Solomon, W. M.
- Nuclear Fusion, Vol. 53, Issue 9
Kinetic neoclassical transport in the H-mode pedestal
journal, July 2014
- Battaglia, D. J.; Burrell, K. H.; Chang, C. S.
- Physics of Plasmas, Vol. 21, Issue 7
Active spectroscopic measurements of the bulk deuterium properties in the DIII-D tokamak (invited)
journal, October 2012
- Grierson, B. A.; Burrell, K. H.; Chrystal, C.
- Review of Scientific Instruments, Vol. 83, Issue 10
Improved edge charge exchange recombination spectroscopy in DIII-D
journal, August 2016
- Chrystal, C.; Burrell, K. H.; Grierson, B. A.
- Review of Scientific Instruments, Vol. 87, Issue 11
Visible charge exchange spectroscopy at JET
journal, November 1990
- von Hellermann, M. G.; Mandl, W.; Summers, H. P.
- Review of Scientific Instruments, Vol. 61, Issue 11
A Code that Simulates Fast-Ion D α and Neutral Particle Measurements
journal, September 2011
- Heidbrink, W. W.; Liu, D.; Luo, Y.
- Communications in Computational Physics, Vol. 10, Issue 3
In–out impurity density asymmetry in the pedestal region of Alcator C-Mod
journal, November 2013
- Churchill, R. M.; Lipschultz, B.; Theiler, C.
- Nuclear Fusion, Vol. 53, Issue 12
Neutral beam stopping and emission in fusion plasmas I: deuterium beams
journal, May 2000
- Anderson, H.; Hellermann, M. G. von; Hoekstra, R.
- Plasma Physics and Controlled Fusion, Vol. 42, Issue 7
Thermal ion orbit loss and radial electric field in DIII-D
journal, August 2015
- deGrassie, J. S.; Boedo, J. A.; Grierson, B. A.
- Physics of Plasmas, Vol. 22, Issue 8
Poloidal asymmetry of parallel rotation measured in ASDEX Upgrade
journal, July 2012
- Pütterich, T.; Viezzer, E.; Dux, R.
- Nuclear Fusion, Vol. 52, Issue 8