Ion kinetic effect on bifurcated relaxation to a field-reversed configuration in TS-4 CT experiment

Eiichirou Kawamori, Y. Murata, K. Umeda, D. Hirota, T. Ogawa, T. Sumikawa, T. Iwama, K. Ishii, T. Kado, T. Itagaki, M. Katsurai, A. Balandin, Y. Ono

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

The ion kinetic effect on the bifurcated relaxation of merging spheromaks to a field-reversed configuration (FRC) was studied experimentally using varied S*, which is the ratio of the minor radius to the ion skin depth from 1 to 7. The two merging spheromaks were observed to relax to an FRC or a new spheromak depending on whether the initial poloidal eigenvalue was smaller or larger than a threshold value. The threshold initial poloidal eigenvalue for the relaxation to an FRC increased with the decreasing S * value. A decrease in S* promoted the relaxation to an FRC, annihilating the magnetic helicity, in sharp contrast with the conventional Taylor relaxation. Suppression of the low-n mode by the rotation shear of the toroidal modes is the most probable reason why the low-S* condition promotes the relaxation into an FRC.

Original languageEnglish
Pages (from-to)843-848
Number of pages6
JournalNuclear Fusion
Volume45
Issue number8
DOIs
Publication statusPublished - 2005 Aug 1

Fingerprint

spheromaks
kinetics
configurations
ions
eigenvalues
thresholds
retarding
shear
radii

All Science Journal Classification (ASJC) codes

  • Nuclear and High Energy Physics
  • Condensed Matter Physics

Cite this

Kawamori, Eiichirou ; Murata, Y. ; Umeda, K. ; Hirota, D. ; Ogawa, T. ; Sumikawa, T. ; Iwama, T. ; Ishii, K. ; Kado, T. ; Itagaki, T. ; Katsurai, M. ; Balandin, A. ; Ono, Y. / Ion kinetic effect on bifurcated relaxation to a field-reversed configuration in TS-4 CT experiment. In: Nuclear Fusion. 2005 ; Vol. 45, No. 8. pp. 843-848.
@article{4f2b154e8cd84795aea065c2b0c6cf5c,
title = "Ion kinetic effect on bifurcated relaxation to a field-reversed configuration in TS-4 CT experiment",
abstract = "The ion kinetic effect on the bifurcated relaxation of merging spheromaks to a field-reversed configuration (FRC) was studied experimentally using varied S*, which is the ratio of the minor radius to the ion skin depth from 1 to 7. The two merging spheromaks were observed to relax to an FRC or a new spheromak depending on whether the initial poloidal eigenvalue was smaller or larger than a threshold value. The threshold initial poloidal eigenvalue for the relaxation to an FRC increased with the decreasing S * value. A decrease in S* promoted the relaxation to an FRC, annihilating the magnetic helicity, in sharp contrast with the conventional Taylor relaxation. Suppression of the low-n mode by the rotation shear of the toroidal modes is the most probable reason why the low-S* condition promotes the relaxation into an FRC.",
author = "Eiichirou Kawamori and Y. Murata and K. Umeda and D. Hirota and T. Ogawa and T. Sumikawa and T. Iwama and K. Ishii and T. Kado and T. Itagaki and M. Katsurai and A. Balandin and Y. Ono",
year = "2005",
month = "8",
day = "1",
doi = "10.1088/0029-5515/45/8/010",
language = "English",
volume = "45",
pages = "843--848",
journal = "Nuclear Fusion",
issn = "0029-5515",
publisher = "IOP Publishing Ltd.",
number = "8",

}

Kawamori, E, Murata, Y, Umeda, K, Hirota, D, Ogawa, T, Sumikawa, T, Iwama, T, Ishii, K, Kado, T, Itagaki, T, Katsurai, M, Balandin, A & Ono, Y 2005, 'Ion kinetic effect on bifurcated relaxation to a field-reversed configuration in TS-4 CT experiment', Nuclear Fusion, vol. 45, no. 8, pp. 843-848. https://doi.org/10.1088/0029-5515/45/8/010

Ion kinetic effect on bifurcated relaxation to a field-reversed configuration in TS-4 CT experiment. / Kawamori, Eiichirou; Murata, Y.; Umeda, K.; Hirota, D.; Ogawa, T.; Sumikawa, T.; Iwama, T.; Ishii, K.; Kado, T.; Itagaki, T.; Katsurai, M.; Balandin, A.; Ono, Y.

In: Nuclear Fusion, Vol. 45, No. 8, 01.08.2005, p. 843-848.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Ion kinetic effect on bifurcated relaxation to a field-reversed configuration in TS-4 CT experiment

AU - Kawamori, Eiichirou

AU - Murata, Y.

AU - Umeda, K.

AU - Hirota, D.

AU - Ogawa, T.

AU - Sumikawa, T.

AU - Iwama, T.

AU - Ishii, K.

AU - Kado, T.

AU - Itagaki, T.

AU - Katsurai, M.

AU - Balandin, A.

AU - Ono, Y.

PY - 2005/8/1

Y1 - 2005/8/1

N2 - The ion kinetic effect on the bifurcated relaxation of merging spheromaks to a field-reversed configuration (FRC) was studied experimentally using varied S*, which is the ratio of the minor radius to the ion skin depth from 1 to 7. The two merging spheromaks were observed to relax to an FRC or a new spheromak depending on whether the initial poloidal eigenvalue was smaller or larger than a threshold value. The threshold initial poloidal eigenvalue for the relaxation to an FRC increased with the decreasing S * value. A decrease in S* promoted the relaxation to an FRC, annihilating the magnetic helicity, in sharp contrast with the conventional Taylor relaxation. Suppression of the low-n mode by the rotation shear of the toroidal modes is the most probable reason why the low-S* condition promotes the relaxation into an FRC.

AB - The ion kinetic effect on the bifurcated relaxation of merging spheromaks to a field-reversed configuration (FRC) was studied experimentally using varied S*, which is the ratio of the minor radius to the ion skin depth from 1 to 7. The two merging spheromaks were observed to relax to an FRC or a new spheromak depending on whether the initial poloidal eigenvalue was smaller or larger than a threshold value. The threshold initial poloidal eigenvalue for the relaxation to an FRC increased with the decreasing S * value. A decrease in S* promoted the relaxation to an FRC, annihilating the magnetic helicity, in sharp contrast with the conventional Taylor relaxation. Suppression of the low-n mode by the rotation shear of the toroidal modes is the most probable reason why the low-S* condition promotes the relaxation into an FRC.

UR - http://www.scopus.com/inward/record.url?scp=23844456584&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=23844456584&partnerID=8YFLogxK

U2 - 10.1088/0029-5515/45/8/010

DO - 10.1088/0029-5515/45/8/010

M3 - Article

AN - SCOPUS:23844456584

VL - 45

SP - 843

EP - 848

JO - Nuclear Fusion

JF - Nuclear Fusion

SN - 0029-5515

IS - 8

ER -