Role of molecular effects in divertor plasma recombination

Kukushkin, A. S.; Krasheninnikov, S. I.; Pshenov, A. A.; Reiter, D.

doi:10.1016/j.nme.2016.12.030

Title: Role of molecular effects in divertor plasma recombination

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Abstract

Molecule-Activated Recombination (MAR) effect is re-considered in view of divertor plasma conditions. A strong isotopic effect is demonstrated. In deuterium plasmas, the reaction chain through D₂⁺ formation, usually considered dominant and included in 2D edge plasma models, is negligible. However, in this case the other branch, through D^-, usually neglected in modelling, becomes relatively strong. The overall share of MAR in divertor plasma recycling stays within 20%. The operational parameters of the divertor plasmas, such as the peak power loading on the divertor targets or the pressure limit for partial detachment of the divertor plasma, are insensitive to the presence of MAR, although the latter may be important for correct interpretation of the divertor diagnostics.

Authors:: Kukushkin, A. S.; Krasheninnikov, S. I.; Pshenov, A. A.; Reiter, D.

Publication Date:: Tue Aug 01 00:00:00 EDT 2017

Research Org.:: Univ. of California, San Diego, CA (United States)

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

OSTI Identifier:: 1346429

Alternate Identifier(s):: OSTI ID: 1534182

Grant/Contract Number:: FG02-04ER54739

Resource Type:: Published Article

Journal Name:: Nuclear Materials and Energy

Additional Journal Information:: Journal Name: Nuclear Materials and Energy Journal Volume: 12 Journal Issue: C; Journal ID: ISSN 2352-1791

Publisher:: Elsevier

Country of Publication:: Netherlands

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; tokamak; divertor; recombination; MAR

Citation Formats


                    Kukushkin, A. S., Krasheninnikov, S. I., Pshenov, A. A., and Reiter, D. Role of molecular effects in divertor plasma recombination.  Netherlands: N. p., 2017. 
Web.  doi:10.1016/j.nme.2016.12.030.

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                    Kukushkin, A. S., Krasheninnikov, S. I., Pshenov, A. A., & Reiter, D. Role of molecular effects in divertor plasma recombination.  Netherlands.  https://doi.org/10.1016/j.nme.2016.12.030

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                    Kukushkin, A. S., Krasheninnikov, S. I., Pshenov, A. A., and Reiter, D. Tue .  
"Role of molecular effects in divertor plasma recombination".  Netherlands.  https://doi.org/10.1016/j.nme.2016.12.030.

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@article{osti_1346429,

  title        = {Role of molecular effects in divertor plasma recombination},

  author       = {Kukushkin, A. S. and Krasheninnikov, S. I. and Pshenov, A. A. and Reiter, D.},

  abstractNote = {Molecule-Activated Recombination (MAR) effect is re-considered in view of divertor plasma conditions. A strong isotopic effect is demonstrated. In deuterium plasmas, the reaction chain through D2+ formation, usually considered dominant and included in 2D edge plasma models, is negligible. However, in this case the other branch, through D-, usually neglected in modelling, becomes relatively strong. The overall share of MAR in divertor plasma recycling stays within 20%. The operational parameters of the divertor plasmas, such as the peak power loading on the divertor targets or the pressure limit for partial detachment of the divertor plasma, are insensitive to the presence of MAR, although the latter may be important for correct interpretation of the divertor diagnostics.},

  doi          = {10.1016/j.nme.2016.12.030},

  journal      = {Nuclear Materials and Energy},

  number       = C,

  volume       = 12,

  place        = {Netherlands},

  year         = {Tue Aug 01 00:00:00 EDT 2017},

  month        = {Tue Aug 01 00:00:00 EDT 2017}

}

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