2.ポテンシャル計測・電場とプラズマ閉じ込め研究

II-2
࣎ࢷࣤࢨࣔࣜゝῼ࣬㞹ሔ࡛ࣈࣚࢫ࣏㛚ࡋ㎲ࡴ◂✪
Diagnostics of Plasma-Confining Potentials for
Improving Plasma Confinement due to Electric Fields
ᖲ⏛ ┷ྍ㸡࣏࢝ࣤ 10 ࢡ࣭ࣜࣈ
➻ἴኬᏕࣈࣚࢫ࣏◂✪ࢬࣤࢰ࣭
HIRATA Mafumi, GAMMA 10 Group
Plasma Research Centre, University of Tsukuba
☚ሔ᪁ᘟ࡞ࡻࡾࣈࣚࢫ࣏㛚ࡋ㎲ࡴ⿞⨠࡞࠽࠷࡙ࠉ㞹న/㞹ሔ࡞ࡻࡾࣈࣚࢫ࣏㛚ࡋ㎲ࡴᛮ⬗
ࡡྡྷ୕ࡢࠉ࣐࣭ࣚᆵ├⥲⣌⿞⨠ࡢࡵ࡛ࡻࡽࠉITER ➴ࡡࢹ࣏࢜ࢠ࣬ࣉࣛ࢜ࣜᆵ⎌≟⣌ࣈࣚࢫ
࣏㛚ࡋ㎲ࡴ⿞⨠ࡵྱࡴᗀࡂᬉ㐚Ⓩ࡚㢟ⴥ࡝ࣈࣚࢫ࣏㛚ࡋ㎲ࡴࡡᨭၻ࣬ྡྷ୕᪁Ἢ࡚࠵ࡽࠉⴥ
ࡊ࠷㛚ࡋ㎲ࡴᛮ⬗ࡡྡྷ୕࠿ぜࡼࡿ࡙࠷ࡾࠊ≁࡞ࢹ࣏࢜ࢠ࣬ࣉࣛ࢜ࣜᆵࣈࣚࢫ࣏࡚ࡢࠉ㧏ࣈ
ࣚࢫ࣏㛚ࡋ㎲ࡴᨭၻ H ࣓࣭ࢺࡷࠉᙼ᪁ྡྷ࢙ࢾ࣭ࣜ࢟㛚ࡋ㎲ࡴࢅྡྷ୕ࡈࡎࡾහ㒂㍲㏞㝸ባ
㸝ITB㸞ࡡᙟᠺ࠿Ⓠぜࡈࡿࡒ࠿ࠉࡐࡡ∸⌦ᶭᵋ࡞ࡗ࠷࡙ࡢ࠷ࡱࡓ࡞༎ฦよ᪺ࡈࡿࡒ࡛ࡢゕ࠻
ࡍࠉ㞹న/㞹ሔ࡞ࡻࡾࣈࣚࢫ࣏㛚ࡋ㎲ࡴྡྷ୕ࡡ◂✪ࡢࠉᰶ⼝ྙ࢙ࢾ࣭ࣜ࢟ࡡᐁ⏕໩࡞ྡྷࡄ࡙
ᚪさ୘ྊḖ࡝◂✪ㄚ㢗࡚࠵ࡾࠊ
ࡆࡿ࡞ᑊࡊࠉ⿞⨠❻㒂ࢅᣚࡗ࣐࣭ࣚᆵᐁ㥺⿞⨠ࡢࠉ㞹Ꮔࢦ࢕ࢠࣞࢹࣞࣤຊ⇍(ECH)࡞ࡻࡽ
㞹Ꮔࢅ㐽ᢝⓏ࡞㧏Ὼ㹺㧏㏷໩ࡊࠉ࣐࣭ࣚ❻㒂࡞ᑊࡊ㞹Ꮔࡡୌ㒂ࢅࣆ࣭࡛ࣞࡊ࡙Ὦࡿฝࡈࡎࠉ
ࡆࡿ࡞ࡻࡽࣈࣚࢪࡡ㞹న/㞹ሔࢅ⮤ᅹ࡞ᙟᠺ㹺โᚒ࡚ࡀࡾ࡛࠷࠹≁㛏ࢅᣚࡖ࡙࠽ࡽࠉࡆࡿࢅ
Ὡ࠾ࡊ࡙ࠉ௙ᙟᘟࣈࣚࢫ࣏⿞⨠࡞ࡵᬉ㐚Ⓩ࡝∸⌦ᶭᵋよ᪺ࢅ᥆㐅ࡊ࡙࠷ࡾࠊ[1-3]
≁࡞㞹న࡛ࣈࣚࢫ࣏㍲㏞ࡡ∸⌦ᶭᵋࢅよ᪺ࡌࡾ࡛࠷࠹ふⅤ࠾ࡼࠉࣈࣚࢫ࣏㛚ࡋ㎲ࡴᨭၻ
ࢅフ౮ࡌࡾࡒࡴࡡࣈࣚࢫ࣏チ᩷Ἢ࡛ࡊ࡙ࠉ≁࡞༟ୌࣈࣚࢫ࣏㹺ࢨࣘࢴࢹ࡚㞹నࡡ✭㛣ฦᕱゝ
ῼ࡛ࣈࣚࢫ࣏㛚ࡋ㎲ࡴຝᯕࢅ᳠ゞࡌࡾࡒࡴࡡ࢕࢛ࣤ㹺࢙ࢾ࣭ࣜ࢟㹺ࢪ࣋ࢠࢹࣜࡡ✭㛣ฦᕱゝ
ῼࢅ⾔࠹❻᥾኶⢇Ꮔゝῼჹ࢙࣬ࢾ࣭ࣜ࢟ฦᯊჹ࢓ࣝ࢕࡛ࣈࣚࢫ࣏㍲㏞ࢅ᳠ゞࡌࡾࡒࡴࡡ࣏
࢕ࢠࣞࢲࣔࣤࢾࣜࣈ࣭ࣝࢹ࣬༖ᑙమ᳠ฝჹࢅ⏕࠷ࡒ X ⥲ཀྵࡦ୯ᛮ⢇Ꮔࡡ㸧ḗඔ᧔ാࢅ⾔࠷ࠉ
㞹ሔ࠿ᯕࡒࡌࣈࣚࢫ࣏㛚ࡋ㎲ࡴຝᯕࡡレ⣵࡝✪᪺ࢅ㐅ࡴ࡙࠷ࡾࠊ[4,5]
ᮇሒ࿈࡚ࡢࠉࡆࡿࡼࡡ∸⌦ᶭᵋよ᪺ࡡࡒࡴࡡゝῼჹࡡⓆᒈ࡞ࡗ࠷࡙㏑࡬ࡾ࡛භ࡞ࠉࡐࡡ
⤎ᯕ࡛ࡊ࡙ᚋࡼࡿࡒ㸝㸦㸞᩺ᆵゝῼჹ࢓ࣝ࢕࡞ࡻࡾ✭㛣Ⓩ࣬᫤㛣Ⓩ࡞ን໩ࡌࡾ࢕࢛ࣤ㛚ࡋ
㎲ࡴ㞹న࡛❻᥾኶࢕࢛ࣤ㞹Ὦ࠾ࡼࠉ㞹Ꮔࢦ࢕ࢠࣞࢹࣞࣤຊ⇍(ECH)ࣂ࣭࣠ࡡቌኬ➴࡞ఔ࠹
㞹నࡡ᛬㐅ᒈ[ᚉᮮࡡ⣑ 4 ಶࡡ࢕࢛ࣤ㛚ࡋ㎲ࡴ㧏㞹న(3 kV)ࢅ㐡ᠺ]࡞ࡻࡾࠉᙁ࠷ᙼ᪁ྡྷ㞹ሔ
ࢨ࢓࣭(dEr/dr)ࡡ⏍ᠺࠉࡐࡿ࡞ఔ࠹࣏࢝ࣤ 10 ࢬࣤࢹࣚࣜ㒂࣬ࣈࣚࢫ࣏❻㒂୦㒂࡞࠽ࡄࡾ᥺
ິࡡᢒโ[2]ࠉཀྵࡦࣈࣚࢫ࣏㛚ࡋ㎲ࡴࡡᨭၻ࡞ᑊࡌࡾᮇ㈻Ⓩ࡝ຝᯕ࡞ࡗ࠷࡙[3]ࠉ୕オࡡරమ
Ⓩᐁ㥺ౚ࡛ࡊ࡙♟ࡌࠊࡆࡡ⤎ᯕࢅᚺ⏕ࡊࠉ㸝㸧㸞࣐࣭ࣚᆵ⿞⨠࡞ࡻࡾิࡴ࡙ࡡࠔᙼ᪁ྡྷ㍲
㏞㝸ባࠕࡡ⿞⨠❻㒂ࢅὩ⏕ࡊࡒ⬗ິโᚒࢅࠉࣁࣛ࢓㒂࢛ࣆ㹺࢓ࢠࢨࢪ ECH ࡞ࡻࡽᙟᠺࡊࡒ
ළ⎌≟ࡡ㧏Ὼ㞹Ꮔᒒ࡞ࡻࡾࢬࣤࢹࣚࣜ㒂㞹ᏄὮࢅ⏍ᠺࡊ࡙ᐁ᪃ࡊࡒࠊ㞹Ꮔࡡୌ㒂ࡢ❻᥾኶
ࡊᙼ᪁ྡྷ࡞ළ⎌≟ࡡᑻᡜ୦ᴗᛮ㞹నࡡࣁࣤࣈ/㞹నࣅ࣭ࢠࢅషࡽࠉࡐࡡ୦ഁ࡞ᙟᠺࡈࡿࡒཬ
ᑊ➚ྒࡡ Er ࡞ࡻࡾ E×B ࣆ࣭ࣞࡡཬ㌹ࠉཀྵࡦ ᙁ࠷ Er ࢨ࢓࣭/㧏࣍ࣜࢷ࢔ࢨࢷ࢔࣭ᙟᠺࢅ⾔
࠷ࠉࠔᙼ᪁ྡྷ㍲㏞㝸ባࠕࡡ⏍ᠺ࡛஗ὮῸࡡᢒโ࣬ᙼ᪁ྡྷ㍲㏞ᢒโ࡞ࡻࡾ㛚ࡋ㎲ࡴᨭၻ࠿㉫
ࡆࡾࡆ࡛࠿ゝῼࡈࡿࡒࠊᮇゝῼౚ࡞ࡗ࠷࡙ెࡎ࡙ሒ࿈ࡌࡾࠊ
[1] T. Cho et al., Physical Review Letters 97 (2006) 055001.
[2] T. Cho et al., Physical Review Letters 94 (2005) 085002.
[3] T. Cho et al., Nuclear Fusion 45 (2005) 1650.
[4] M. Hirata et al., Trans. Fusion Science and Technology 47 (2005) 215.
[5] M. Hirata et al., Review of Scientific Instruments 75 (2004) 3631.