Proceedings of the 1st Annual Meeting of Particle Accelerator Society of Japanand the 29th Linear Accelerator Meeting in Japan (August 4 - 6, 2004, Funabashi Japan)

ELECTRON CLOUD BUILD-UP AND BEAM INSTABILITIESIN THE KEK-PS AND J-PARC
Takeshi Toyama, Kazuhito Ohmi, Susumu Igarashi, Takako Miura, Masahito Tomizawa,KEK, Oho 1-1, Tsukuba, Ibaraki 305-0801, JAPANAbstract
High intensity positive particle accelerators and storage rings suffer from electron cloud. It causes fast transverse
beam instabilities, false signals on beam monitors and pressure rise due to electron stimulated gas desorption and iondesorption. The on-going project, J-PARC (Japan Proton Accelerator Research Complex) may have a similar situation.
The electron cloud build-up was observed at the KEK-PS. Experimental results are reported. Beam stabilities
concerning with the electron cloud is predicted for the J-PARC 3 GeV rapid cycling synchrotron and 50 GeVSynchrotron.

KEK-PS࠽ ࡻ ࡦ J-PARC ࡞ ࠽ ࡄ ࡾ 㞹 Ꮔ 㞴 ࡡ Ⓠ ⏍ ࡛ 㞹 Ꮔ 㞴 ୘ Ꮽ ᏽ ᛮࡆࡆ࡚ࡢࠉJ-PARC࡚ࡡ㞹Ꮔ㞴࡞ࡻࡾࣄ࣭࣑ࡡᏭᏽᛮ࡞ࡗ࠷࡙ぜ✒ࡵࡽࠉࡆࡿࡼࡡᇱ࡛ࡊࡒゝ⟤ࡡಘ㢏⌟ᅹᘋス୯ࡡJ-PARCࡢࠉ3 GeVࢨࣤࢠࣞࢹࣞࣤᛮࢅ☔ヾࡌࡾୌࡗࡡ᪁Ἢ࡛ࡊ࡙KEK-PS࡚⾔ࡖ࡙࠷㸝RCS㸞࡛50 GeVࢨࣤࢠࣞࢹࣞࣤ㸝MR㸞ࢅ⏕࠷࡙ࠉ ࡾᐁ㥺ࡡሒ࿈ࢅࡌࡾࠊ
LINAC࠾ࡼࡡࣄ࣭࣑ࢅຊ㏷ࡊࠉࡐࡿࡑࡿࡡࢹࢴࣈ࢙
ࢾ࣭࡚ࣜ࢟ࠉ1 MW, 750 MW ࡡኬᙁᗐ㝟Ꮔࣄ࣭࣑ࢅ
㸧㸣J-PARC࡞࠽ࡄࡾ㞹Ꮔ㞴୘Ꮽᏽᛮᚋࡾゝ⏤࡚࠵ࡾ[1]ࠊࣛࣤࢡ㒂ฦࡢᖳ࠾ࡼࢤ࣐ࢴࢨࣘࢼࣤࢡ࠿㛜ጙࡈࡿࡾࠊࣁࣤࢲ࠵ࡒࡽ㝟Ꮔᩐᨲᑏක࠿࡮࡛ࢆ࡜ฝ࡝࠷㝟Ꮔࣛࣤࢡࡡሔྙ࡚ࡢ㸝Np 㸞ࠤ4x1013 ࠉࣁࣤࢲ㛏ࠤ16-110 m࡚࠵ࡽࠉ㞹Ꮔ
㸝LHCࡢᨲᑏක࠿ᨥ㒼Ⓩ㸞ࠉ㞹Ꮔ㞴ࡢࠉࣄ࣭࣑ࣞࢪ㞴 ୘ Ꮽ ᏽ ᛮ ࡞ ࣄ ࣭ ࣑ 㞹 Ὦ ࢅ โ 㝀 ࡈ ࡿ ࡙ ࠷ ࡾ Los㸝㝟Ꮔࡡ┷✭ᐖჹባ࡫ࡡ⾢✲㸞ࠉ࠵ࡾ࠷ࡢࣄ࣭࣑࡛
AlamosࡡPSR[2]࡛㢦జࡡࣂ࣒࣭ࣚࢰ࡛࡝ࡖ࡙࠷ࡾࠊ
ṟ⏻࢝ࢪ࡛ࡡ⾢✲࡞ࡻࡖ࡙Ⓠ⏍ࡌࡾ㞹Ꮔ࠿ᘤ㔘࡛ࡐࡡ௙࡞ࠉCERN, BNL, KEK, SLACࡡ㝟Ꮔࣛࣤࢡࠉ࡝ࡖ࡙ࠉᠺ㛏ࡌࡾ࡛⩻࠻ࡼࡿ࡙࠷ࡾࠊ
㝟㞹Ꮔࣛࣤࢡ࡚ࡵࠉ㞹Ꮔ㞴୘Ꮽᏽᛮࠉ㞹Ꮔ㞴࡞ࡻࡾࣁࣤࢲࣄ࣭࣑࡛ࢤ࣭ࢪࢷ࢔ࣤࢡࣄ࣭࣑࡚Ⓠ⏍ࡡᶭࣄ࣭࣑࣓ࢼࢰ࣭ࡡಘྒỗ᯹ࠉ࠽ࡻࡦ┷✭ᝇ໩࠿ሒ࿈
ᵋ࠿ࡷࡷ␏࡝ࡾࡡ࡚ࠉࡐࡿࡑࡿ࡞ࡗ࠷࡙⩻ᐳࡌࡾࠊ
ࡈࡿ࡙࠷ࡾ[3]ࠊࡐࡡࡒࡴࠉJ-PARCࡵ㞹Ꮔ㞴࡞ࡻࡾ
2.1 ࣁࣤࢲࣄ࣭࣑࡞ࡻࡾ㞹Ꮔ㞴[4]ၡ㢗࠿ᠩᛍࡈࡿ࡙࠷ࡾࠊୌ᪁࡚ࠉISISࡡ㝟Ꮔࢨࣤࢠ
13ࣞࢹࣞࣤࡡࡻ࠹࡞ࠉࡷࡢࡽNp ࠤ1.25x10 ࡚㸧ࣁࣤࢲࣄ࣭࣑ࣞࢪࠉ࠵ࡾ࠷ࡢࣄ࣭࣑࡛ṟ⏻࢝ࢪ࡛ࡡ⾢✲ࡡ㝟Ꮔࢅຊ㏷ࡊ࡝࠿ࡼࠉ㞹Ꮔ㞴࠿ふῼࡈࡿ࡙࠷࡝࠷࡞ࡻࡖ࡙Ⓠ⏍ࡌࡾ㞹Ꮔࡢࠉᙔิࡢᩐᩐ10 eV࡚࠵ࡾౚࡵ࠵ࡾ[3]ࠊJ-PARCࡡ㞹Ꮔ㞴࡞㛭౿ࡌࡾᇱᮇⓏ࡝
࠿ࠉࣄ࣭࣑ࡡ㞹ሔ࡞ࡻࡖ࡙᭩ኬᩐ100 eVࡱ࡚ຊ㏷ࡈ
ࣂ࣒࣭ࣚࢰࢅ⾪㸦࡞ࡱ࡛ࡴࡾࠊࡿࠉ┷✭ᐖჹባ࡞⾢✲ࡊࠉ㸧ḗ㞹Ꮔࢅ྄ࡀฝࡌࠊࡆ㸦㸣ࡢࡋࡴ࡞⾪㸦J-PARCࡡ㝟Ꮔࢨࣤࢠࣞࢹࣞࣤࡡࣂ࣒࣭ࣚࢰࡿࡼ㸧ḗ㞹Ꮔ࠿ࡈࡼ࡞ᚃ⤾ࡡࣄ࣭࣑࡞ຊ㏷ࡈࡿ࡙ྜྷ
ᵕࡡࡆ࡛࠿㉫ࡆࡾࠊ┷✭ᐖჹ⾪㟻ࡡ㸧ḗ㞹Ꮔᨲฝ౿ᩐࡢ㏳ᖏ㸦ࡻࡽኬࡀ࠷ࡡ࡚ࠉࢾࢫ࣐⟤Ⓩ࡝㞹ᏄࡡቌṢ࠿㉫ࡆࡽࠉ✭㛣㞹Ⲭ࡚㣤࿰ࡌࡾࡱ࡚⧖ࡽ㏁ࡈࡿࡾࠊ
௑ᅂࡡゝ⟤ࡢࠉゝ⟤᫤㛣ࡡ▯⦨ࡡࡒࡴ࡞ࠉ  㞹Ꮔ㞴ࡡᠺ㛏ࡡࢨ࣐࣭ࣖࣝࢨࣘࣤゝ⟤ࠉ  㣤࿰ࣝ࣊ࣜ࡞㐡ࡊࡒ㞹Ꮔ㞴࡞ࡻࡾࣄ࣭࣑୘Ꮽᏽᛮࡡゝ⟤ࠉࡡ㸧ṹ㝭࡚⾔ࡖ࡙࠷ࡾࠊ
ࡱࡍࠉ㞹Ꮔ㞴ࡡᠺ㛏ࡡゝ⟤࡞࠽ࡄࡾิ᭿㞹Ꮔࡡ㔖ࡢ௧ୖࡡࡻ࠹࡞௫ᏽࡊࡒࠊࣄ࣭࣑ࣞࢪ࡞ࡻࡾሔྙࡢࠉ
Los AlamosࡡPSRࡡ⤊㥺࠾ࡼࠉࣛࣤࢡ㸦ࢰ࣭ࣤ㸝
P㸞ᙔࡒࡽࡡࣄ࣭࣑ࣞࢪ๪ྙ4x10-6 ࠉ࠽ࡻࡦ㝟Ꮔ㸦ࡗࡡࣞࢪᙔࡒࡽ㞹ᏄⓆ⏍㔖100 e-/p࡛ࡊ࡙ᑙࡀࡓࡈࡿࡒࠉ
㝟Ꮔ1಴࠿㸦m㏳㐛ࡌࡾ࡛ࡀࡡࣞࢪ࡞ࡻࡾ㞹ᏄⓆ⏍⋙
4.4x10-6 e-/(m·p)ࢅ㐲⏕ࡊࡒࠊṟ⏻࢝ࢪࡡሔྙࡢࠉCO࡛H2 ࠿୹ᠺฦ࡛ࡊ࡙2x10-7Pa࡚ࡡ㞹ᏄⓆ⏍⋙7.7x10-9e-/(m·p)ࢅ౐ࡖࡒࠊ
㸧ḗ㞹Ꮔᨲฝ౿ᩐࡢࠉ

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Proceedings of the 1st Annual Meeting of Particle Accelerator Society of Japanand the 29th Linear Accelerator Meeting in Japan (August 4 - 6, 2004, Funabashi Japan)" 2 (E) = " 2, max

E

1.44

Emax 0.44 + (E / Emax )1.44
࡞ᚉࡖࡒࠊࡆࡆ࡚Emax=200eVࠉδ2,max=2.1ࠊゝ⟤⤎ᯕࢅᅒ㸦࡞♟ࡌࠊࣄ࣭࣑ࣞࢪ࡞ࡻࡾ㞹Ꮔࡡᐞ୙࠿ᨥ㒼Ⓩ࡚࠵ࡖࡒࠊ◒⥲ࡢࣁࣤࢲᙟ≟࡚࠵ࡾࠊ̲ࢅ⦢᪁ྡྷ
!
ᗑᵾࠉlBࢅࣁࣤࢲ㛏࡛ࡊ࡙sin( π z / lB ) ࢅ௫ᏽࡊࡒࠊ
ࣄ࣭࣑㏳㐛ࡡᚃ༖࡞㞹Ꮔቌಶ⋙࠿ቌ࠻࡙࠷ࡾ
㸝trailing-edge multipacting㸞ࠊᩐࣁࣤࢲࡡ㏳㐛ᚃ࡞ᏽᖏ≟ឺ࡞㐡ࡌࡾࡆ࡛࠿ࢂ࠾ࡾࠊ

ࡡࢸ࣭ࢰࡢ࡝࠷ࡡ࡚100࡛௫ᏽࡊࡒࠊ2ḗ㞹Ꮔᨲฝຝ⋙࡞ࡗ࠷࡙ࡢࠉ྘⛸ᮞ㈻࡞ࡗ࠷࡙ࡡῼᏽ࠿࡝ࡈࡿ࡙
࠷ࡾࠊ⾪㟻ฌ⌦ࢅ᪃ࡈ࡝࠷࡛㏳ᖏδ2,max ࡢ2ࢅ㉰࠻ࡾࠊ
RCS࡚᤿⏕ࡈࡿࡾࢬ࣐ࣚࢴࢠࢲ࢘ࣤࣁ࣭ࡢහ㟻ࢅ
TiNࢤ࣭ࢷ࢔ࣤࢡࡌࡾࡡ࡚ࠉ2ḗ㞹Ꮔᨲฝຝ⋙ࡢ༎ฦᑚࡈࡂ࡝ࡾ࡛᭿ᙽࡈࡿࡾࠊࡱࡒࠉδ(0)=0.5−0.8࡛࠷࠹ῼᏽ⤎ᯕ࠿ሒ࿈ࡈࡿ࡙࠷ࡾ࠿ࠉࡆࡡຝᯕࡢfactor⛤ᗐ࡚࠵ࡖࡒ[6]ࠊࣁࣤࢲᙟ≟࡞ࡻࡾᙫ㡢ࡢࠉη (neutralization factor)
࡞2-3ಶ⛤ᗐࡡࣁࣚࢵ࢞ࡡ⏍ࡋࡾࡆ࡛࠿ሒ࿈ࡈࡿ࡙࠷
ࡾ[3]ࠊ
2.2 ࢤ࣭ࢪࢷ࢔ࣤࢡࣄ࣭࣑࡞ࡻࡾ㞹Ꮔ㞴[7]

MRࡡࣆࣚࢴࢹࢹࢴࣈ࡚ࡢࠉࢤ࣭ࢪࢷ࢔ࣤࢡࣄ࣭
࣑࡞ࡻࡾ㐔࠷ཱིฝࡊ࠿஢ᏽࡈࡿ࡙࠷ࡾࠊṟ⏻࢝ࢪ࡛
ࡡ⾢✲࡚Ⓠ⏍ࡌࡾ㸦ḗ㞹Ꮔࡢࠉ୕㏑ࡡ㏳ࡽᑛ࡝࠷ࠊࡊ࠾ࡊࠉDCࣄ࣭࣑࡝ࡡ࡚ࣄ࣭࣑࣎ࢷࣤࢨࣔࣜ࡞㞹Ꮔ࠿‸ࡱࡽ⤾ࡄ࡙ࡊࡱ࠹࡛ࠉ1 ms⛤ᗐ࡚୘Ꮽᏽᛮࡡ㜀ೋ࡞㐡ࡊ࡙ࡊࡱ࠹ࡆ࡛࡞࡝ࡾࠊᐁ㝷࡞ࡢࠉࣄ࣭࣑ࡡᶋ᪁ྡྷࡡᣲິ࡞ࡻࡖ࡙㞹Ꮔࡡᣲᖕࡢቌኬࡊࠉࣄ࣭࣑ࡡᮨ⦙࠾ࡼ㞫⬲ࡊࠉባ࡞ᙔࡒࡽࠉྺ཭࠵ࡾ࠷ࡢ㸧ḗ㞹Ꮔᨲฝ࠿஢᝷ࡈࡿࡾࠊࢨ
࣐࣭ࣖࣝࢨࣘࣤ࡞ࡻࡾ࡛ࠉ2x10-7 Pa㸝㞹ᏄⓆ⏍⋙
7.7x10-9/(m.p)㸞ࡡ┷✭࡚ࡢࠉ୘Ꮽᏽᛮࡡၡ㢗ࡢ࡝࠷ࠊࡈࡼ࡞ࠉ㞹ᏄⓆ⏍⋙࠿ቌ࠻ࠉ10-6-10-5/(m.p)࡞࡝ࡾ
ᅒ㸦 J-PARC ࡚ࡡ㞹Ꮔ㞴ࡡᠺ㛏ࠊ (a) (b) RCSࡡ ථ࡛ࠉࣄ࣭࣑ࡡ㞟㡚Ⓩ࡝ᶋ᪁ྡྷᣲິ࠿ᘤ㔘࡞࡝ࡽࠉ୕ᑏ ࠉ ཱི ฝ ࡊ ࠉ (c) (d) MR ࡡ ථ ᑏ ࠉ ཱི ฝ ࡊ ࢙ ࢾ ࣜオࡻࡽኣࡂࡡ㞹Ꮔ࠿ባ࡞⾢✲ࡊࠉmultipacting ࠿㉫࣭࡚࢟ࡡゝ⟤ೋࠊᶋ㍂ࡢࣛࣤࢡ࡞Ἒࡖࡒ㊝㞫ࠉࡀࡾࡻ࠹࡞࡝ࡽࠉࣄ࣭࣑ࢦ࢕ࢫࡡቌኬ࠿㉫ࡀጙࡴࡾࠊ
⦢ ㍂ ࡢ 㞹 Ꮔ ቌ ಶ ⋙ 㸝 㞹 Ꮔ 㞴 ᐠ ᗐ /1ḗ 㞹 Ꮔ ᐠ ᗐ 㸞 ࠊ㞹ᏄⓆ⏍࠿ࠉࣞࢪࡊࡒ㝟Ꮔ࡛ባ࡛ࡡ⾢✲࡞ࡻࡾሔྙࡵࠉࣄ࣭࣑ࢦ࢕ࢫࡡቌኬ࠿㉫ࡀጙࡴࡾ㞹ᏄⓆ⏍⋙୘Ꮽᏽᛮࡡึᏽࡢࠉࢤ࣭ࢪࢷ࢔ࣤࢡࣄ࣭࣑㎾జ࡚
ࡡೋࡢྜྷᵕ࡞10-6-10-5/(m.p)࡚࠵ࡖࡒࠊ
⾔ࡖࡒࠊωeσz/c~100>>1࠿ᠺࡽ❟ࡖ࡙࠷ࡾࡡ࡚ࠉࡆࡡ┷✭ࡡᅸງࡢ10-7-10-6 Paࢅ┘ᵾ࡞ࡊ࡙࠷ࡾࡡ࡚[1]ࠉ
㎾జࡢᠺࡽ❟ࡗࠊMR࡚ࡢࠉ㞹Ꮔ㞴ᐠᗐࡡ᭩ኬೋ࡚
multipacting ࠿㉫ࡆࡾ࡚ࣝ࣊ࣜࡢ࡝࠷࠿ࠉࣄ࣭࣑ࣞ
୘Ꮽᏽᛮࡡ㜀ೋࢅ㉰࠻ࡾࠊRCS࡚ࡢࠉཱིฝࡊ᫤࡞㜀ࢪ࠿ࠉ㞹ᏄⓆ⏍⋙ 10-6-10-5/(m.p)࡞ᑊᚺࡌࡾೋࡻࡽኬ
ೋ࡞㎾࠷ೋࢅཱིࡾࠊ
ࡀ࠷࡛ࠉ୘Ꮽᏽᛮ࠿Ⓠ⏍ࡌࡾྊ⬗ᛮ࠿࠵ࡾࠊ
⾪㸧 J-PARCࣛࣤࢡࡡ㞹Ꮔ㞴୘Ꮽᏽᛮ㸨㸣KEK-PS࡞࠽ࡄࡾ㞹Ꮔ㞴ࡡふῼ┘Ⓩࡢࠉ(1) 㞹Ꮔ㞴ᠺ㛏ࡡࢨ࣐࣭ࣖࣝࢨ࡛ࣘࣤẒ㍉ࢅ⾔࠹ࠉ(2) TiNࢤ࣭ࢷ࢔ࣤࢡࡡຝᯕࢅᐁῼࡌࡾࠉ
ࡆ࡛࡚࠵ࡾࠊ

ゝ⟤⤎ᯕࡡಘ㢏ᛮࡢࠉථງࣂ࣒࣭ࣚࢰࡡಘ㢏ᛮ࡞ࡻࡾࠊ୘☔ᏽ࡝さ⣪ࡢࠉࣄ࣭࣑ࣞࢪ㔖ࠉ1ḗ࠽ࡻࡦ2ḗ㞹Ꮔᨲฝຝ⋙ࠉࣁࣤࢲᙟ≟࡚࠵ࡾࠊࣄ࣭࣑ࣞࢪ㔖࡞ࡗ࠷࡙ࡢࠉⲬ㞹ንᥦࣆ࢚࢕ࣜࠉࢤ
࣒࣭ࣛࢰ࡚Ⓠ⏍ࡌࡾ㞹Ꮔࢅࠉࢮࣝࢿ࢕ࢺ☚ሔࠉ࠵ࡾ࠷ࡢࢠࣛ࢓ࣛࣤࢡ㞹ᴗ࡚཭㞗ࡊࠉโᚒ୘⬗࡝ࣄ࣭࣑ࣞࢪࢅࢸࢧ࢕ࣤೋ௧ୖ࡞ᢒ࠻ࡿࡣࠉ୕オ௫ᏽࡡ⠂ᅑහ࡞཭ࡱࡾぜ㎲ࡲ࡚࠵ࡾ[5]ࠊ
㧏࢙ࢾ࣭ࣜ࢟㝟Ꮔࡡ⾢✲࡞ࡻࡾ1ḗ㞹Ꮔᨲฝ౿ᩐᅒ㸧 Electron sweeping detector

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Proceedings of the 1st Annual Meeting of Particle Accelerator Society of Japanand the 29th Linear Accelerator Meeting in Japan (August 4 - 6, 2004, Funabashi Japan)!
!"!Electron sweeping detector!#$%&'()*+,!
!!!!!Sweeping&-./01232," 45678!9:# 456);<,!

!
!"!Electron sweeping detector#$%&'()*+,!
!!!!-./0&12345678#9:;<%&'2=>?!

!

!!!!#@A5B,&'CDEFG;78&'HICJKLM!

!"!Electron sweeping detector!#$%&'()*+,!

!!!!NOPQFGBBR6ST)&'UVCWX5;<%,!

!!!!!12 GeV!-./00/123456789:4;<)*+,!
!!!!!&'()=>?@ABC,!

⌟ᅹ౐⏕ࡊ࡙࠷ࡾ⿞⨠㸝ᅒ㸧㸞ࡢࠉLos AlamosࡡPSR ࡡ ࢡ ࣜ ࣭ ࣈ ࡚ 㛜 Ⓠ ࡈ ࡿ ࡒ “electron sweeping
㸩㸣㆗ㄵdetector”࡚࠵ࡾ[2]ࠊKEK-PS MR࡚㞹Ꮔ㞴୘Ꮽᏽᛮࡢࠉ
඙࡞௫ᏽࡊࡒࣄ࣭࣑ࣞࢪ⋙ 4x10-6/turn࡚ࣞࢪ࠿ᣚ⌟ᅹふῼࡈࡿ࡙࠷࡝࠷ࠊ
⤾Ⓩ࡞Ⓠ⏍ࡌࡾ࡛ࠉୌຊ㏷࿔᭿ࡡࣄ࣭࣑࿔ᅂᩐ104106ࢅ⩻៎ࡊ࡙ࠉ⭶ኬ࡝ࣞࢪ㔖࡞࡝ࡽ㟸⌟ᐁⓏ࡝ࡆ࡛
3.1 ࣁࣤࢲࣄ࣭࣑࠿ࢂ࠾ࡾࠊࡊ࠾ࡊࠉ୘Ꮽᏽᛮࡡᠺ㛏ࡌࡾࡡ࡞ᚪさ࡝ࣁࣤࢲࣄ࣭࣑࡚ࡢࠉࢹࣚࣤࢩࢨࣘࣤ௛㎾࠽ࡻࡦࣆ
~1 ms ௧ୖ࡚ࡡࣞࢪ࡛ࡌࡾ࡛ࠉ㉫ࡀ࠹ࡾ⛤ᗐ࡚࠵ࡾࠊࣚࢴࢹࢹࢴࣈ௛㎾࡚ࠉ㞹Ꮔ㞴ࡡಘྒ࠿ふῼࡈࡿࡾࠊࣄ࣭࣑ࣞࢪࡡ⟮⌦࠿㔔さ࡚࠵ࡾ࡛⩻࠻ࡼࡿࡾࠊᅒ㸨ࠉ㸩࡞ࡢࢹࣚࣤࢩࢨࣘࣤ௛㎾࡚ࡡῼᏽ⤎ᯕࢅ♟ᐁ㥺ࡡよᯊࠉTiNࢦࣤࣈࣜῼᏽࡢ௑ᚃࡡㄚ㢗࡚࠵ࡾࠊࡊࡒࠊsweeping㞹ᅸࢅ༰ຊࡊ࡝࠷࡛ባ࡞⾢✲ࡌࡾ㞹ୖᓧ⩇ெẮࠉ㫵㣣ᖶኯẮ࡞ࡢᐁ㥺࡚࠽ᡥఎ࠷࠷ࡒࡓ࠷ࡒࠊᯐ├ᶖẮࠉ㔕⏛ᩝ❮Ắࠉຊ⸠ⱩᶖẮࠉఫ⸠ᗛኯ㑳Ắࠉ⳥ⵞ⏛⩇༡ẮࠉᏄ࠿ふῼࡈࡿࡾࠊࣁࣤࢲᩐࢅን࠻ࡾ࡛ࠉ㞹Ꮔಘྒࡢ⏣⏛ួ஦Ắࠉ⏍ฝົᐃẮࠉᶋㆺ㤶ẮࠉථỜྚ㑳Ắࠉኬ᲻༐ᗀẮࠉ
5ࣁࣤࢲ௧ୖ࡚ࡢふῼࡈࡿ࡝࠾ࡖࡒࠊࡆࡿࡢࠉ㏻⤾㧏ᒜ೸Ắ࡞ࡢ᭯⏕࡝㆗ㄵࠉ♟ြࢅ࠷ࡒࡓ࠷ࡒࠊࡌࡾࣁࣤࢲ࡞ࡻࡖ࡙㞹Ꮔࡡ⵫✒࠿ቌ㛏ࡈࡿࡾ㞹Ꮔ㞴
ࡡᛮ㈻࡞ୌ⮬ࡊ࡙࠷ࡾࠊࡱࡒࠉsweeping pulse㞹ᅸ~ཤ⩻ᩝ⊡-850 Vࢅ༰ຊࡌࡾ࡛ࠉࡐࡡࢰ࢕࣐ࣤࢡ࡚✭㛣୯ࡡ㞹
[1] “Accelerator Technical design report for J-PARC” editedᏄ࠿ᢪࡊฝࡈࡿ࡙ኬࡀ࡝ಘྒ࡛ࡊ࡙ふῼࡈࡿࡒࠊ
3.2 ࢤ࣭ࢪࢷ࢔ࣤࢡࣄ࣭࣑[2]ᅒ㸪࡞ࠉࣆࣚࢴࢹࢹࢴࣈ࡚RF㞹ᅸ࢛ࣆ࠾ࡼࡡ྘᫤
[3]
็࡞sweepࡈࡿࡒ㞹Ꮔಘྒࢅ♟ࡊࡒࠊࣄ࣭࣑ᙁᗐࠉࣄ࣭࣑ࣞࢪ࡞౪Ꮛࡊࠉࡱࡒ㣤࿰ࡌࡾࡆ࡛࠿ࢂ࠾ࡖࡒࠊ [4][5]ࣄ࣭࣑ᙁᗐ3.6x1012ࡡ᫤ࠉ㞹Ꮔ⏍ᠺ⋙~1x1010 e-/m.sࠉ[6]
᫤ᏽᩐ~0.3 s࡚࠵ࡖࡒࠊࡆࡡሔᡜ࡚η~30%࡛࡝ࡾࠊ

by Y. Yamazaki, KEK-report 2002-13.
R. Macek, 31st ICFA Advanced Beam Dynamics
Workshop on Electron-Cloud Effects "ECLOUD'04"
Napa (California), April 19-23, 2004.
Presentations at "ECLOUD'04".
K. Ohmi, et al., PRST 5 114402 (2002).
T. Toyama, Presentation at "ECLOUD'04".
K. Ohmi, http://www-accps.kek.jp/J-PARC/beam_instability/epi_ohmi_2002Jun12.pdf.

[7] K. Ohmi, Presentation at "ECLOUD'04".

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