U.S. Department of EnergyOffice of Scientific and Technical Information
Argon Pumpout by ICRF Waves in C-Mod L- and I-mode Plasmas
Abstract
Pumpout of argon ions by ICRF waves has been observed in C-Mod deuterium L- and I-mode plasmas that had a substantial hydrogen fraction. The effect is manifested by a reduction of core argon x-ray brightness up to a factor of 90% on time scales of tens of milliseconds following injection of ICRF power. For Ar^16+, the pumpout is strongest for hydrogen minority concentrations between 0.25 and 0.4, when the ICRF waves are not expected to result in minority heating. Modeling with the TORIC code suggests that the pumpout process occurs when the H/D mode conversion layer overlaps with the 2nd harmonic impurity resonance layer. The magnitude of the argon pumpout is independent of ICRF power above an apparent threshold of ~500 kW, independent of electron density and appears to decrease as the plasma current is increased. Potential application as a heavy impurity control tool in reactors is discussed.
- Authors:
-
- OSTI
- Publication Date:
- DOE Contract Number:
- SC0014264
- Research Org.:
- Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Plasma Science and Fusion Center
- Sponsoring Org.:
- USDOE Office of Science (SC), Fusion Energy Sciences (FES)
- Subject:
- 70 PLASMA PHYSICS AND FUSION TECHNOLOGY
- OSTI Identifier:
- 1887970
- DOI:
- https://doi.org/10.7910/DVN/B4II5P
Citation Formats
Rice, J. E., Lin, Y., Perks, C. J., Reinke, M. L., Marmar, E. S., Cao, N., Gao, C., Sciortino, F., Wukitch, S. J., and Wright, J. Argon Pumpout by ICRF Waves in C-Mod L- and I-mode Plasmas. United States: N. p., 2022.
Web. doi:10.7910/DVN/B4II5P.
Rice, J. E., Lin, Y., Perks, C. J., Reinke, M. L., Marmar, E. S., Cao, N., Gao, C., Sciortino, F., Wukitch, S. J., & Wright, J. Argon Pumpout by ICRF Waves in C-Mod L- and I-mode Plasmas. United States. doi:https://doi.org/10.7910/DVN/B4II5P
Rice, J. E., Lin, Y., Perks, C. J., Reinke, M. L., Marmar, E. S., Cao, N., Gao, C., Sciortino, F., Wukitch, S. J., and Wright, J. 2022.
"Argon Pumpout by ICRF Waves in C-Mod L- and I-mode Plasmas". United States. doi:https://doi.org/10.7910/DVN/B4II5P. https://www.osti.gov/servlets/purl/1887970. Pub date:Wed Jun 08 04:00:00 UTC 2022
@article{osti_1887970,
title = {Argon Pumpout by ICRF Waves in C-Mod L- and I-mode Plasmas},
author = {Rice, J. E. and Lin, Y. and Perks, C. J. and Reinke, M. L. and Marmar, E. S. and Cao, N. and Gao, C. and Sciortino, F. and Wukitch, S. J. and Wright, J.},
abstractNote = {Pumpout of argon ions by ICRF waves has been observed in C-Mod deuterium L- and I-mode plasmas that had a substantial hydrogen fraction. The effect is manifested by a reduction of core argon x-ray brightness up to a factor of 90% on time scales of tens of milliseconds following injection of ICRF power. For Ar^16+, the pumpout is strongest for hydrogen minority concentrations between 0.25 and 0.4, when the ICRF waves are not expected to result in minority heating. Modeling with the TORIC code suggests that the pumpout process occurs when the H/D mode conversion layer overlaps with the 2nd harmonic impurity resonance layer. The magnitude of the argon pumpout is independent of ICRF power above an apparent threshold of ~500 kW, independent of electron density and appears to decrease as the plasma current is increased. Potential application as a heavy impurity control tool in reactors is discussed.},
doi = {10.7910/DVN/B4II5P},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Jun 08 04:00:00 UTC 2022},
month = {Wed Jun 08 04:00:00 UTC 2022}
}