1168

˙ ‫঺ڀݚ‬հৗ఻ಋߴిքՃ଎‫ڀݚ‬ͷ࠷લઢ
KEK Ճ଎‫ࢪڀݚث‬ઃѨ෦ ఩࿠
tetsuo.abe@kek.jp
2018 ೥ (ฏ੒ 30 ೥) 2 ݄ 4 ೔1

Ͱ 2.856 GHzɼཧԽֶ‫( ॴڀݚ‬ཧ‫ޫ౓ًߴͱ )ݚ‬Պֶ‫ݚ‬͸͡Ίʹ‫ڀ‬ηϯλʔ (JASRI) ͕‫ڞ‬ಉӡӦ͢Δ೔ຊॳͷ X ઢࣗ༝ৗ఻ಋՃ଎ͱ͸ɼৗ఻ಋঢ়ଶ (௒఻ಋͰ͸ͳ͍ঢ়ଶ)ిࢠϨʔβʔՃ଎‫ ث‬SACLA Ͱ࢖ΘΕ͍ͯΔ C όϯυͷۚଐͰ‫ڥ‬ք৚݅Λ༩͑ͨྖҬ಺ʹɼߴप೾ (Radio-ৗ఻ಋՃ଎؅Ͱ͸ 5.712 GHz Ͱ͋Δɻৗ఻ಋՃ଎‫Ͱث‬Frequency waveɼҎԼʮRFʯɼϚΠΫϩ೾ͱ΋‫)͏ݴ‬͸ɼٕज़ͷਐาʹΑΓɼΑΓߴ͍Ճ଎प೾਺Λ࠾༻͢Δ

Λ౤ೖ͢Δ͜ͱͰྭৼ͞ΕΔిքͰՙిཻࢠΛՃ଎͢Δ

͜ͱ͕ग़དྷΔΑ͏ʹͳ͖ͬͯͨɻ͔͠͠ɼେిྗͷϚΠ

͜ͱͰ͋Δɻ‫ڥ‬ք৚݅Λ༩͑ΔྖҬ͸ԁ౵‫ܗ‬ঢ়͕ҰൠతΫϩ೾ͱߴ͍प೾਺Λ࢖͑͹ɼ͍͘ΒͰ΋ߴ͍Ճ଎ޯ഑

ͰɼՃ଎Ϟʔυͷ‫ৼڞ‬ઑӶ౓ (Q ஋) Λߴ͘͢Δ͜ͱͰɼ͕ (Ճ଎‫ݱ࣮ )ͯ͠ͱث‬Մೳ͔ͱ͍͏ͱɼͦ͏Ͱ͸ͳ͍ɻߴ͍Ճ଎ిքΛޮ཰తʹ࣮‫ݱ‬ग़དྷΔɻ·ͨɼՃ଎‫ث‬ͷӡՃ଎ޯ഑Λߴ͘͢ΔͱɼՃ଎ߏ଄಺ͷۚଐද໘ʹ͓͚Δ

స࣌ʹ͸ɼͦͷྖҬ಺͸ (௒ߴ) ਅۭঢ়ଶʹ͢Δɻ‫ڥ‬քిք‫্͕͕౓ڧ‬ΓɼͦΕʹΑΓਅۭதͷେ์ి͕ൃੜ͠

৚݅Λ༩͑Δۚଐʹ͸ɼߴ७౓ͷಔ͕࢖ΘΕΔ͜ͱ͕

ͯɼՃ଎ͷͨΊʹ஝ੵͨ͠ి࣓քΤωϧΪʔͷ่յ (Ҏଟ͍ɻԼɼʮϒϨʔΫμ΢ϯʯ) ͕‫͏·͖ͯ͠ى‬ɻ͋Δ RF ύϧߴ͍Ճ଎ޯ഑ʹΑΔཻࢠՃ଎ (ߴిքՃ଎) ͸ɼߴΤε಺ͰϒϨʔΫμ΢ϯ͕ൃੜ͢ΔͱɼͦΕҎ߱ͷϚΠΫωϧΪʔՃ଎‫ͯͬͱʹث‬ॏཁͱͳΔ͹͔ΓͰͳ͘ɼՃ଎

ϩ೾͸શ൓ࣹ͠ɼՃ଎ߏ଄ʹϚΠΫϩ೾Λ౤ೖग़དྷͳ͘

‫ث‬ͷখ‫ܕ‬Խʹ΋‫͕ܨ‬Δɻৗ఻ಋߴిքՃ଎Ͱ͸ɼۚଐදͳΔɻ·ͨɼ‫ޙ‬ଓͷ RF ύϧεͰ΋Ҿ͖ଓ͖ϒϨʔΫμ໘ͷϚΠΫϩ೾ʹΑΔൃ೤Λ཈͑ΔͨΊɼύϧεӡసΛ΢ϯ͕ൃੜ͢Δ͜ͱ͕ଟ͍ɻͭ·Γɼৗ఻ಋߴిքՃ଎

ߦ͏͜ͱ͕ଟ͍ɻͨͱ͑͹ɼRF ύϧε෯͕ 200 ns Ͱ‫܁‬Ͱ͸ɼ͍͔ʹϒϨʔΫμ΢ϯͷൃੜ཰ (ϒϨʔΫμ΢ϯΓฦ͕͠ 50 Hz ͷ৔߹Ͱ͸ɼ࿈ଓ೾ͷ৔߹ͱൺ΂ͯɼฏ཰) ΛԼ͛Δ͔͕࠷΋ॏཁͳ՝୊ͱͳΔɻ

−9‫ൃۉ‬೤ྔ͸ 200 × 10

× 50 = 10−5ഒʹখ͘͞ͳΔɻϒϨʔΫμ΢ϯ཰ΛԼ͛Δํ๏ͱͯ͠͸ɼ଱ѹͷߴ͍ຊߘͰ͸ɼಛ‫ݶ͍ͳ͠ه‬ΓɼύϧεӡసΛ૝ఆ͢ΔɻۚଐΛ༻͍Δํ๏΋ߟ͑ΒΕΔɻͨͱ͑͹ɼDC ߴిѹৗ఻ಋՃ଎ʹ͓͍ͯɼΑΓߴ͍Ճ଎ޯ഑Λ࣮‫͢ݱ‬Δ࣮ͨ‫ݧ‬ͷ݁ՌͰ͸2 ಔΑΓ΋νλϯ΍εςϯϨεͷํ͕଱Ίͷ࠷΋؆୯ͳํ๏͸ɼՃ଎ߏ଄ʹ౤ೖ͢ΔϚΠΫϩ೾ѹ͸ͣͬͱߴ͍͜ͱ͕෼͔͍ͬͯΔɻ͔͠͠ɼి‫఻ؾ‬ಋͷిྗΛ্͛Δ͜ͱͰ͋Δɻ͔͠͠ɼߴΤωϧΪʔՃ଎཰ɼ೤఻ಋ཰ɼՃ޻ੑɼ஋ஈͳͲΛ૯߹తʹධՁ͢Δͱɼ‫Ͱث‬Α͘࢖͏ΫϥΠετϩϯͳͲͷϚΠΫϩ೾‫ݯ‬͸ൃ೤ಔʹউΔࡐྉ͸ࠓͷͱ͜Ζͳ͍ͷͰɼৗ఻ಋՃ଎ߏ଄ʹ΍଱ѹͳͲͷ‫ݶ‬քʹΑΓɼ࠷େग़ྗ͸਺े MW ͷΦʔ͸ಔΛ༻͍Δ͜ͱ͕ҰൠతͰ͋ΔɻμʔͰ͋ΓɼೖྗిྗΛ্͛Δ͜ͱʹ͸‫ݶ‬ք͕͋ΔɻͦϨʔβʔɾϓϥζϚՃ଎ʹ͸‫ݪ‬ཧతͳՃ଎ޯ഑ͷ੍‫ݶ‬͜ͰɼΑΓߴ͍Ճ଎ޯ഑Λ࣮‫͢ݱ‬Δ΋͏ͻͱͭͷํ๏ͱ͕ͳ͘ɼߴΤωϧΪʔՃ଎‫΁ث‬ͷԠ༻Λ໨ࢦͨ͠‫͕ڀݚ‬ͯ͠ɼप೾਺Λ্͛ͯՃ଎ϞʔυͷΤωϧΪʔີ౓ΛߴਐΊΒΕ͍ͯΔɻҰํͰɼଟஈՃ଎΍ཅిࢠͷՃ଎͕ࠔΊΔ͜ͱ͕ߟ͑ΒΕΔɻ୯Ґ௕͋ͨ͞ΓͷՃ଎ޮ཰Ͱߟ

೉ͳ͜ͱͳͲΛߟ͑Δͱɼ·ͩ·ͩ՝୊͸ଟ͍ɻ‫ݱ‬ஈ֊͑ͯ΋ɼ௒఻ಋՃ଎ͷ৔߹͸࠷దͳप೾਺͕ଘࡏ͢Δ͕Ͱɼ਺ TeV ྖҬͷϦχΞίϥΠμʔΛͦ͏ԕ͘ͳ͍ক

(ۭಎࡐྉͷ࢒ཹ఍߅͕ 10 nΩ Ͱɼ2K ͷԹ౓Ͱӡస͢དྷʹ࣮‫͢ݱ‬ΔͨΊʹ͸ɼৗ఻ಋߴిքՃ଎͕༗๬ͱߟ͑

Δ৔߹͸ɼ1.3 GHz[1])ɼৗ఻ಋՃ଎ͷ৔߹͸ɼप೾਺ΛΒΕΔɻCERN ͷ CLIC ‫ܭ‬ը͸ɼ·͞ʹৗ఻ಋߴిք

্͛Ε͹্͛ΔఔɼՃ଎ޮ཰͸্͕ΔɻՃ଎प೾਺ͷྫՃ଎ʹ‫ͮ͘ج‬ϦχΞίϥΠμʔͰ͋Γ (CLIC ʹ͍ͭͯΛ‫͛ڍ‬ΔͱɼߴΤωϧΪʔՃ଎‫( ߏػڀݚث‬KEK) ͷి͸ɼୈ 3 અͰղઆ)ɼ100 MV/m ‫ڃ‬ͷߴ͍Ճ଎ޯ഑Λ૝

1ࢠཅిࢠೖࣹ‫࢖Ͱث‬ΘΕ͍ͯΔ S όϯυ ৗ఻ಋՃ଎؅
1 1-2 GHzɼ2-4 GHzɼ4-8 GHzɼ8-12 GHz ͷଳҬ (ͷߴप೾)ΛɼͦΕͧΕɼL όϯυɼS όϯυɼC όϯυɼX όϯυͱ‫Ϳݺ‬ɻ
2 DC ͱ RF Ͱ଱ѹͷ܏޲͕ಉ͔͡͸‫ݱ‬ஈ֊Ͱ͸෼͔͍ͬͯͳ͍ɻ

169
169

ఆ͍ͯ͠Δɻ100 MV/m ͷՃ଎ޯ഑Λ࣮‫͢ݱ‬Ε͹ɼ10͸ɼൺֱత୯७ͳߏ଄Ͱେ͖ͳ‫ݮ‬ਰྗ͕ಘΒΕΔํ๏ͰɼΩϩϝʔτϧͷ‫ Ͱ཭ڑ‬1 TeV ͷՃ଎͕ग़དྷΔɻ·ͨɼߴ

CLIC ΍ SuperKEKB ओϦϯάͳͲͷଟ͘ͷৗ఻ಋՃ଎

ిքՃ଎ٕज़͸ɼՃ଎ߏ଄ͷখ‫ܕ‬ԽΛՄೳʹ͠ɼ์ࣹޫ

ߏ଄Ͱ࠾༻͞Ε͍ͯΔɻ‫ݯ‬ɼҩྍ༻Ճ଎‫ث‬ɼՄൖ‫ ܕ‬X ઢ‫Ͳͳݯ‬ɼ޿ൣғͳԠ༻ՄೳੑΛ͍࣋ͬͯΔɻຊߘͰ͸ɼCLIC ‫ܭ‬ըΛத৺ʹల։͞Ε͍ͯΔৗ఻ಋ
ߴిքՃ଎‫ڀݚ‬ɼ͓Αͼؔ࿈͢Δ‫ૅج‬త‫ڀݚ‬ͷ‫ݱ‬ঢ়ͱల๬ʹ͍ͭͯɼஶऀͷࢹ఺͔Βղઆ͢Δɻ

(a)

(b)

3

ৗ఻ಋϦχΞίϥΠμʔ CLIC
CLIC (Compact Linear ColliderɼʮΫϦοΫʯͱ‫)͏ݴ‬͸ɼͦͷ໊ͷ௨ΓɼίϯύΫτͳ͜ͱ (খ͍͜͞ͱ) ͕ಛ௃ͷిࢠɾཅిࢠϦχΞίϥΠμʔͰ͋ΔɻͦͷίϯύΫ
τੑ͸ɼߴ͍Ճ଎Ϟʔυप೾਺Λ࢖͏͜ͱʹΑ࣮ͬͯ‫ݱ‬͠ɼඞવతʹৗ఻ಋߴిքՃ଎͕࢖ΘΕΔɻCLIC Ͱ͸౰ॳɼՃ଎Ϟʔυप೾਺ͱͯ͠ 30 GHz Λ࠾༻͍͕ͯͨ͠ɼ
࠶౓࠷దԽΛ‫ݕ‬౼ͨ݁͠Ռɼ‫ࡏݱ‬ͷઃ‫Ͱܭ‬͸ 12 GHz ʹप೾਺ΛԼ͍͛ͯΔ4 ɻ͜ͷप೾਺͸ɼ͔ͭͯ೔ຊͰ‫ݕ‬౼͞Ε͍ͯͨ Global Linear Collider (GLC) ΍ถࠃͰ‫ݕ‬౼

(c)

(d)

͕ਐΊΒΕ͖ͯͨ Next Linear Collider (NLC) ͷप೾਺ (11.4 GHz) ʹ͔ۙͬͨͨΊɼप೾਺͕ 12 GHz ʹมߋ͞Εͨࡍʹɼৗ఻ಋߴిքՃ଎‫ͯؔ͠ʹڀݚ‬ɼCERN(Ԥभ)ʖ KEK(೔ຊ)ʖ SLAC(ถࠃ) ͷ 3 ‫ྗڠࡍࠃۃ‬ମ੍͕ਤ 1: Ұൠతͳৗ఻ಋՃ଎؅ͷσΟεΫͱ಺෦ྖҬ (Ճ্ཱ͕ͪͬͨ5 ɻ଎ߏ଄)ɻ(a) ඇ‫ݮ‬ਰηϧ (ૠೖਤ͸൓ରଆͷ໘)ɻ(b) ಋ

CLIC ‫ܭ‬ը͸ɼ‫ࡏݱ‬ɼ֓೦ઃ‫[ ॻܭ‬2] ͕‫׬‬੒ͨ͠ஈ֊

೾؅‫ݮܕ‬ਰηϧ (ૠೖਤ͸൓ରଆͷ໘)ɻ࣮‫Ͱػ‬͸ɼ্Լ

Ͱ͋Δɻͦͷදࢴ (ਤ 2) ͔Β΋Θ͔ΔΑ͏ʹɼCLIC Ճࠨӈͷಋ೾؅୺ʹϚΠΫϩ೾‫ٵ‬ऩମ͕૷ర͞ΕΔɻ(c)଎‫ث‬͸খ͍͞ɻ·ͨɼ௚ઢՃ଎‫ ͕ث‬2 ຊฏߦʹฒΜͰ͍ඇ‫ݮ‬ਰՃ଎؅ͷ಺෦ྖҬɻ(c) ಋ೾؅‫ݮܕ‬ਰՃ଎؅ͷ಺

Δ͜ͱ͕Θ͔Δɻ͜Ε͸ɼCLIC ͕ʮ2 ϏʔϜՃ଎ (Two෦ྖҬɻbeam acceleration)ʯͱ͍͏ํࣜΛ࠾༻͍ͯ͠ΔͨΊͰ͋Δɻਤ 2 ͷࠨଆʹ͋Δͷ͕υϥΠϒϏʔϜϥΠϯɼӈଆ͕ओϏʔϜϥΠϯͰ͋Δɻ

2ৗ఻ಋՃ଎؅ͷߏ଄௨ৗɼৗ఻ಋՃ଎؅͸ɼਤ 1(a) ʹࣔ͢Α͏ͳʮσΟεΫʯΛ਺ेຕελοΫͯ͠઀߹͢Δ͜ͱͰɼਤ 1(c) ͷΑ͏ʹۚଐͰ‫ڥ‬ք৚݅Λ༩͑ͨྖҬΛ࡞ΓɼͦͷྖҬ಺ʹप‫ظ‬తͳՃ଎ిքΛཱͯΔߏ଄ʹͳ͍ͬͯΔ (ຊߘͰ͸ʮσΟεΫɾελοΫํࣜʯͱ‫)Ϳݺ‬ɻ͜Ε͸Ұछͷಋ೾؅͕ͩɼΞΠϦεߏ଄ (ϏʔϜ͕௨Δখ݀) ͕͋Δ͜ͱʹΑΓɼϚΠΫϩ೾ͷҐ૬଎౓Λޫ଎ͱ౳͘͢͠Δ
͜ͱ͕Ͱ͖ɼߴΤωϧΪʔͷిࢠ (·ͨ͸ཅిࢠ) ΛͦͷҐ૬଎౓ͷ೾ʹ৐ͤͯՃ଎͢Δ͜ͱΛՄೳʹ͢Δɻʮඇ‫ݮ‬ਰߏ଄ (Undampedਤ 1(a),(c) ʹ͋Δ΋ͷ͸ɼ
structure)ʯͱ‫ݺ‬͹ΕΔՃ଎؅Ͱ͋ΓɼϏʔϜόϯν͕௨աͨ͠‫࢒ʹޙ‬Δ༗֐ͳߴ࣍ϞʔυΛੵ‫ۃ‬తʹ͸‫ݮ‬ਰਤ 2: CLIC ͷ֓೦ઃ‫[ ॻܭ‬2] ͷදࢴɻ

ͤ͞Δ͜ͱ͸ͳ͍ (ۚଐද໘ʹ͓͚Δδϡʔϧൃ೤ͷΈͰΏͬ͘Γ‫ݮ‬ਰ͢Δ)ɻϦχΞίϥΠμʔͷΑ͏ʹϚϧ

ਤ 3 ʹ CLIC ͷશମਤΛࣔ͢ɻ·ͣɼॳஈઢ‫ܗ‬Ճ଎‫ث‬νόϯνӡస͕ඞཁͳ৔߹͸ɼߴ࣍ϞʔυΛੵ‫ۃ‬తʹ‫ݮ‬ʹ͓͍ͯɼL όϯυ (1 GHz) ͷΫϥΠετϩϯΛ࢖ͬ

ਰͤ͞Δʮ‫ݮ‬ਰߏ଄ (Damped structure)ʯ͕ඞཁͱͳ

ͯిࢠΛ 2 GeV ·ͰՃ଎͢Δɻ͜͜Ͱͷόϯνִؒ͸Δɻ‫ݮ‬ਰߏ଄ʹ͸‫ز‬छྨ͔͋Γɼਤ 1(b),(d) ʹ͋Δͷ͸ಋ೾؅‫ݮܕ‬ਰߏ଄ͱ‫ݺ‬͹Ε͍ͯΔՃ଎؅Ͱ͋Δ3 ɻ͜Ε
3 ಋ೾؅ͷःஅप೾਺ΛՃ଎Ϟʔυप೾਺ͷগ্͠ʹઃఆ͠ɼՃ଎

ϞʔυΛηϧ಺ʹด͡ࠐΊͭͭɼߴ࣍Ϟʔυ͸͢΂ͯಋ೾؅΁Ҿ͖ग़͢ํࣜɻ
4 ਖ਼֬ʹ͸ɼ11.994 GHz Ͱ͋Δɻ
5 ࠷ۙ͸ɼதࠃͷਗ਼՚େֶ΋ՃΘΓɼ4 ‫͍͖ͯͯͬͳʹۃ‬Δɻ

3170

޲͚ͯ 90%Ҏ্ͷޮ཰Λ໨ࢦͨ͠ΫϥΠετϩϯͷ։

0.5 GHz Ͱ͋Δɻͦͷ‫ޙ‬ɼDelay loops Λ࢖ͬͯόϯνִؒΛѹॖ͠ɼ12 GHz ͷόϯνִؒΛ࣋ͭόϯντϨ

ൃ [4] ΍ɼίϯύΫτͳଟஈύϧεѹॖٕज़ͷ։ൃ [5]ΠϯΛ࡞ΓɼυϥΠϒϏʔϜϥΠϯʹೖࣹ͢ΔɻυϥΠ΋ਐΊΒΕ͍ͯΔɻ·ͨɼࠓ‫ޙ‬ͷ༧ఆͱͯ͠͸ɼ2019ϒϏʔϜϥΠϯ͔ΒऔΓग़͞Εͨ 12 GHz ͷେిྗϚΠ

ʙ2020 ೥ʹɼEuropean Strategy for Particle PhysicsΫϩ೾͸ɼಋ೾؅Λ௨ͬͯɼओϏʔϜϥΠϯʹ౤ೖ͞Εʹ͓͍ͯɼCERN ͷকདྷϓϩδΣΫτʹ FCC (FutureΔɻ͜ͷ 2 ϏʔϜՃ଎ͷ‫ݪ‬ཧ࣮ূ͸ɼCTF (CLIC Test

Circular Collider) ͔ CLIC ͷͲͪΒʹ͢Δ͔ΛܾΊΔ

Facility) ʹ͓͍ͯ‫͍ͯྃ͠׬‬Δɻ

༧ఆͰ͋Δɻ

ද 1: CLIC ͷ֤εςʔδʹ͓͚ΔओͳσβΠϯύϥϝʔλɻ

CLIC ͷओϏʔϜϥΠϯͷՃ଎ߏ଄ (X όϯυͷৗ఻ಋՃ଎؅) ͷϕʔεϥΠϯઃ‫ܭ‬͸΄΅‫͍ͯͬ·ݻ‬Δɻਤ

4 ͸ɼKEK ͕੡࡞ͨ͠࠷৽ͷ CLIC ϓϩτλΠϓՃ଎ϧϛϊγςΟ

380 GeV

1.5 TeV

3 TeV

؅ (TD26CC K1) Ͱ͋ΔɻCLIC ϓϩτλΠϓՃ଎؅

1.5

3.7

5.9

ʮTʯ
ͷίʔυωʔϜ (։ൃՃ଎؅໊) ͷ࠷ॳͷจࣈ͸ɼՃ଎ޯ഑ [MV/m]

72

72/10072/100(Travelling waveɿਐߦ೾)ɼ·ͨ͸ɼʮSʯ(Standing waveɿఆࡏ೾) Ͱ͋Δɻ୯Ґ௕͋ͨ͞ΓͷγϟϯτΠϯϐʔμશ௕ [km]

11.4

29

50

ϯεͰՃ଎ޮ཰Λߟ͑Ε͹ɼ௨ৗ͸ਐߦ೾ͷํ͕༗རύϧε‫܁‬ฦ཰ [Hz]

50

50

50

ͰɼCLIC ͷ৔߹΋ਐߦ೾Λ࢖͏͕ɼ‫ڀݚ‬։ൃஈ֊Ͱ

όϯνִؒ [ns]

0.5

0.5

0.5

͸ɼ௿͍ೖྗిྗͰߴ͍ిքΛ࡞Γग़ͤΔఆࡏ೾‫ܕ‬Ճόϯν਺/τϨΠϯ

352

312

312

଎ߏ଄Λ࢖ͬͯߴిքࢼ‫ݧ‬Λߦ͏͜ͱͳͲ΋͋ΔͷͰɼ34[10 cm

−2

sec

−1

]

িಥ఺ʹ͓͚Δ

͜ΕΒΛίʔυωʔϜͷ࠷ॳͷจࣈͰ۠ผ͍ͯ͠Δɻ2

ϏʔϜαΠζ

൪໨ʹʮDʯͷจࣈ͕͋Δ৔߹͸ɼ‫ݮ‬ਰߏ଄ (Damped

σx /σy [nm]150/2.9

60/1.5

40/1

structure) ෇͖ͷՃ଎؅ΛදΘ͍ͯ͠ΔɻT ·ͨ͸ TD

σz [ m]

70

44

44

ͷ࣍ʹ͋Δ਺ࣈ͸ɼՃ଎ηϧ਺ΛදΘ͢6 ɻCLIC ϓϩτফඅిྗ [MW]

252

364

589

λΠϓՃ଎؅ͷ։ൃ͸ 2008 ೥ࠒʹ 18 ηϧ͔Β࢝·Γɼࢼ‫ݧ‬ͷ݁ՌΛϑΟʔυόοΫ͠ͳ͕ΒɼT18*˰ TD18*
˰ T24*˰ TD24*˰ TD26CC*ͱਐԽ͖ͯͨ͠ (ਤ 5 ͷInternational Linear Collider (ILC) ಉ༷ɼCLIC ΋ॎ࣠Ͱɼʮ*ʯ͸೚ҙͷจࣈྻΛද͢)ɻͳ͓ɼॏ৺‫ܥ‬ΤωεςʔδϯάΛߟ͓͑ͯΓɼୈ 1 εςʔδͷॏ৺‫ܥ‬ΤϧΪʔ 380 GeV ͷ CLIC ͷओϏʔϜϥΠϯͰ࢖͏༧ఆ

ωϧΪʔ͸ 380 GeV Ͱ͋Δɻ͜ͷΤωϧΪʔ͸ɼHiggs

ͷՃ଎؅͸ 31 ηϧͰ͋Δɻηϧ਺ΛදΘ͢਺ࣈΑΓ‫ޙ‬ͷ෺ཧͷଞɼTop ͳͲͷ෺ཧ΋ߦ͏ͨΊʹબ͹Εͨ [3]ɻ͸ɼͦͷՃ଎؅ͷৄࡉͳ৘ใͰ͋Δɻ࠷‫ޙ‬ͷ TD26CC ͷͦͷ‫ޙ‬ɼ1.5 TeV ͳͲΛ‫ͯܦ‬ɼ࠷ऴతʹ͸ 3 TeV Λ໨ʮCCʯ͸Compact Coupler ΛදΘ͍ͯ͠ΔɻTD24*Ҏ

ࢦ͍ͯ͠Δɻද 1 ʹɼCLIC ͷ֤εςʔδʹ͓͚ΔओͳલͷՃ଎؅Ͱ͸ɼϚΠΫϩ೾͸ϏʔϜύΠϓ (ԁ‫ܗ‬ಋ೾σβΠϯύϥϝʔλΛࣔ͢ɻୈ 1 εςʔδͰ͸Ճ଎ޯ؅) Λհͯ͠ηϧʹ౤ೖ͢ΔҰൠతͳํࣜͰ͋ΔɻҰํɼ

഑ 72 MV/m ࢓༷ͷՃ଎؅Λ࢖͍ɼͦͷ‫ޙ‬ͷεςʔδͰ

TD26CC*Ͱ͸ɼ௚઀ηϧʹϚΠΫϩ೾Λ౤ೖ͠ɼϏʔ͸ɼୈ 1 εςʔδͰ࢖༻ͨ͠Ճ଎؅Λ্ྲྀଆ΁ઃஔɼԼϜύΠϓΛհ͞ͳ͍෼ɼՃ଎ߏ଄͕ίϯύΫτʹͳΔઃྲྀଆʹ 100 MV/m ࢓༷ͷՃ଎؅Λ‫͗ܧ‬଍͢ɻࢀߟ·Ͱ‫͋Ͱܭ‬Δɻਤ 5 ͸ɼςετελϯυͰ RF ίϯσΟγϣ

ʹɼKEK ిࢠཅిࢠೖࣹ‫ث‬ͷ S όϯυৗ఻ಋՃ଎؅ͷχϯά͕‫ͨྃ͠׬‬Ճ଎؅ͷ࠷ऴੑೳΛ·ͱΊͨ΋ͷͰ͋ӡసՃ଎ޯ഑͸ 20 MV/mɼSACLA ͷ C όϯυৗ఻ಋΔɻ࠷ऴతͳ RF ύϧε෯΍Ճ଎ޯ഑͸֤ࢼ‫Ͱݧ‬ҟͳͬՃ଎؅͸ 38 MV/mɼILC ͷ L όϯυ௒఻ಋՃ଎؅Ͱ͸

͍ͯΔɻͦ͜Ͱɼ͜Ε·Ͱͷ X όϯυՃ଎؅ͷߴిք

31.5 MV/m Ͱ͋ΔɻCLIC ͷՃ଎ޯ഑ (100 MV/m) ͸ɼࢼ‫͔ݧ‬ΒಘΒΕͨ‫ݱ‬৅࿦తεέʔϦϯάଇ [6]ɿ͜Ε·Ͱͷߴप೾Ճ଎ߏ଄ͷ 2.5 ഒҎ্Ͱ͋ΔɻͪͳΈʹɼCLIC ͷ‫ݐ‬ઃඅ͸ɼॏ৺‫ܥ‬ΤωϧΪʔ

380 GeV ͷ৔߹ɼ67 ԯεΠεϑϥϯ (೔ຊԁͰ໿ 7700
ԯԁ) ͱࢼࢉ͞Ε͍ͯΔɻෆ֬ఆཁૉ͕ଟ͍ͱ͸ࢥΘΕΔ͕ɼେࡶ೺ʹ‫͑ݴ‬͹ɼILC ͱಉఔ౓Ͱ͋Δɻ·ͨɼ

72 MV/m ͷՃ଎ޯ഑Λ૝ఆ͍ͯ͠Δ CLIC ͷୈ 1 εςʔδͰ͸ɼX όϯυɾΫϥΠετϩϯͷΤωϧΪʔޮ཰΍ RF ύϧεѹॖٕज़Λ޲্ͤ͞Δ͜ͱͰɼΫϥΠετϩϯΛ࢖͏΄͏͕ 2 ϏʔϜՃ଎ํࣜΑΓ΋Ձ֨Λ͞Βʹ҆͘Ͱ͖ΔՄೳੑ͕ఏ‫͞ݴ‬Ε͍ͯΔɻ‫ࡏݱ‬͸ͦΕʹϒϨʔΫμ΢ϯ཰ ∝ (Ճ଎ޯ഑)30 ×(RF ύϧε෯)5 (1)Λ࢖ͬͯɼCLIC ͷεϖοΫ (༗ޮ RF ύϧε෯ɿ180 nsɼ୯Ґ௕͋ͨ͞ΓͷϒϨʔΫμ΢ϯ཰ɿ3 × 10−7 /pulse/m)ʹՃ଎ޯ഑Λεέʔϧͯ͠දࣔͯ͋͠Δɻͭ·Γɼਤ 5
͸ɼCLIC ࢓༷ͷϒϨʔΫμ΢ϯ཰Ͱӡసͨ͠৔߹ʹୡ੒ՄೳͳՃ଎ޯ഑Ͱ͋Δ (ୠ͠ɼ͜͜Ͱ͸ϏʔϜϩʔσΟϯάͷޮՌ͸ߟྀ͍ͯ͠ͳ͍)ɻͳ͓ɼ3 × 10−7 /pulse/m
6 ্Լྲྀͷ݁߹ηϧΛআ͍ͨ‫਺ݸ‬ɻ

4171

ਤ 3: ॏ৺‫ܥ‬ΤωϧΪʔ 380 GeV ʹ͓͚Δ CLIC ͷશମਤɻࢀߟจ‫[ ݙ‬3] ΑΓൈਮɻ-C

TD26CC K1 ͷιϦουϞσϧ (൒ׂ) ͱՃ଎ϞʔυͷిքϕΫτϧɻKEK

T24-Tsin
T18-CERN

T18-KEKSLAC
T18-KEKKEK

-SLAC

C
EK-SLA
TD18-K

TD18-K➠➠
଎؅ɿTD26CC K1(௕͞͸໿ 30 ηϯνϝʔτϧ)ɻ(b)

TD18*

➠

ਤ 4: (a) KEK ͕੡࡞ͨ͠࠷৽ͷ CLIC ϓϩτλΠϓՃ

EK-KEK

TD24*
T24*

T24-KEK-

TD24R0➠TD26CC*ghua-KEK

N1
CC
26

Measured gradients scaled to
180 ns pulse length and−7
3 × 10 breakdown rate

ER
NCE
RN
5#4-KEKKEK
TD
26
CC
N3
TD24-K
EK-KEK-CER
TD24R0N5K2-KEK-KEK
CE
TD24R0RN
5K1-KE
K-KEK

CLIC Prototype Structures

(b)

TD

(a)

Undamped
Damped

T18*
80

90

100

110

120

Unloaded Accel. Gradient [MV/m]ͱ͍͏ϒϨʔΫμ΢ϯ཰͸ɼ೚ҙͷՃ଎؅ͷϒϨʔΫμਤ 5: RF ίϯσΟγϣχϯά‫ʹޙ‬ୡ੒ͨ͠Ճ଎ޯ഑ɻ

΢ϯͰɼͦͷ RF ύϧε಺ͷશόϯν͕ࣦΘΕͨ৔߹ͷ

CLIC ͷεϖοΫʹεέʔϧͯ͠දࣔɻϓϩοτ͸ฏ‫ۉ‬ϧϛϊγςΟ௿Լ͕ 1%Ҏ಺ʹऩ·Δͱ͍͏‫ج‬४Ͱ͋Δɻ஋Λࣔ͠ɼ໼ҹͱՃ଎؅໊͸ɼͦͷՃ଎؅ͷ࠷ऴతͳੑ

࠷ॳͷඇ‫ݮ‬ਰՃ଎؅ (T18*) Ͱ͸ɼ͹Β͖͕ͭ͋Δ΋ೳΛදΘ͢ɻ͜͜ͰͷՃ଎؅໊ʹ͸ɼ੡࡞ऀ໊ (ࠨଆ) ͱͷͷɼ໨ඪͱ͢ΔՃ଎ޯ഑ 100 MV/m Λ֓Ͷୡ੒ग़དྷࢼ‫( ໊ऀݧ‬ӈଆ) Λ‫͋ͯ͠ࡌه‬Δɻ

ͦ͏ͩͱ͍͏݁ՌΛಘΒΕͨɻҰൠతʹɼ‫ݮ‬ਰߏ଄ͷ༗ແͰද໘ిք͸มΘΒͳ͍͸ͣͰ͋Δ͕ɼT18*ʹ‫ݮ‬ਰηϧͷଆ໘ (ਤ 6(a) ͷࢦ͞͠Օॴ) ʹ͓͚Δද໘࣓ք͕ɼ

ߏ଄Λ෇͚ͨ TD18*Λࢼ‫͜ͱͨ͠ݧ‬Ζɼੑೳ͕େ͖͘

ඇ‫ݮ‬ਰʹൺ΂ͯߴ͘ͳΔͱ͍͏ܽ఺͕͋Δɻද໘࣓ք͕

མͪͯ͠·ͬͨɻ͜ͷ໰୊Λଧ։ͨ͠ͷ͕ɼʮද໘࣓քߴ͍ͱ͍͏͜ͱ͸ɼͦ͜Λେ͖͍ද໘ిྲྀ͕ྲྀΕΔͷͰɼޮՌͷॏཁੑͷൃ‫ݟ‬ʯͰ͋ͬͨɻ͜Ε·Ͱ΋ɼՃ଎Ϟʔ

100 MV/m ‫ڃ‬ͷՃ଎ޯ഑Λཱͯͨ৔߹ɼ108 A/cm2 ‫ڃ‬υͷද໘ిք (௨ৗͷৗ఻ಋՃ଎؅Ͱ͸Ճ଎ޯ഑ͷ໿ 2ͷ‫ڊ‬େͳද໘ిྲྀ͕ྲྀΕΔ͜ͱʹͳΔ7 ɻͦͯ͠ɼσΟഒ) ͕ϒϨʔΫμ΢ϯ཰ʹେ͖͘ޮ͘͜ͱ͸஌ΒΕ͍ͯεΫɾελοΫํࣜͷՃ଎؅Ͱ͸ɼͦͷ‫ڊ‬େͳද໘ిྲྀ

͕ͨɼද໘࣓ք΋ɼද໘ిքͱಉఔ౓ʹϒϨʔΫμ΢ϯ͕σΟεΫؒͷ઀߹ՕॴΛ౉Δ͜ͱʹͳΔ (ද໘ిྲྀ͸ɼ཰ΛܾΊ͍ͯΔ͜ͱ͕Θ͔ͬͨͷͰ͋Δ [7, 8]ɻಋ೾؅
‫ܕ‬ͷ‫ݮ‬ਰߏ଄ʹ͸ɼಋ೾؅෦͕։͍͍ͯΔ͜ͱʹΑΓɼ

7 ਓ޻తʹൃੜͤ͞Δද໘ిྲྀີ౓ͱͯ͠͸ɼ࠷େ‫͋Ͱڃ‬Ζ͏ɻ

5
172

(a)

᜖᭼ሩᄖঊॄ

ᾅᾫ̵έඥᥬ

Disk B(a)

Disk Aᣑᩓ᥋ྜ⟠ᡤ
ᣑᩓ᥋ྜ⟠ᡤ(b) ᜖᜖᭼᭐໇

Disk B

Disk A୔‫װ‬ጓ૎

ਤ 6: (a) ‫ݮ‬ਰߏ଄ͷද໘࣓ք‫౓ڧ‬ɻ(b) ‫ݮ‬ਰߏ଄ͷσΟᎺ‫װ‬὿ᾯ

εΫؒ઀߹Օॴͷ SEM ը૾ྫɻഁઢ໼ҹ͸ɼද໘ిྲྀ
ͷྲྀΕΛදΘ͢ɻࠃࡍϫʔΫγϣοϓ MeVArc2015 ʹ͓͚Δ Anitè Pèrez Fontenla ࢯͷൃදεϥΠυΑΓൈਮɻ

(b)

᭐ᄖ

ុᰱ὿ᾯ

(c)

Ꮀዟ὿ᾯ

ሩᄖ

ϏʔϜ࣠ํ޲ʹྲྀΕΔͨΊ)ɻ͜Ε͕Α͘ͳ͍ͱߟ͑Β
ΕΔࣄ࣮ͷྫ͕ਤ 6(b) Ͱ͋Δɻ͜ͷਤ͸ɼߴిքࢼ‫ݧ‬Λऴ͑ͨಋ೾؅‫ܕ‬ͷ‫ݮ‬ਰՃ଎؅ͷηϧͷଆ໘Λ ScanningElectron Microscope (SEM) Ͱ‫ͨ͠࡯؍‬ը૾Ͱɼ;ͨͭͷྡ઀͢Δηϧͷ઀߹Օॴ (ܺؒ) ʹϛΫϩϯαΠζ
ͷո͍͠෺ମ͕‫͑ݟ‬Δɻߴిքࢼ‫ݧ‬લʹ͸‫ݟ‬ΒΕͳ͍ਤ 7: ਗ਼՚େֶ੡ͷ X όϯυɾνϣʔΫϞʔυ‫ݮܕ‬ਰߏͷͰɼେ͖ͳද໘ిྲྀ͕ྲྀΕͨ͜ͱͰൃੜͨ͠΋ͷͰ଄Λ࣋ͭ୯ηϧ‫ۭݧࢼܕ‬ಎ (ఆࡏ೾)ɻ(a) ࢼ࡞‫ػ‬ͷΧο

͋Δ8 ɻTD24*Ͱ͸ɼηϧͷଆ໘‫ܗ‬ঢ়ͳͲΛ޻෉͠ɼද

τϞσϧɻ(b) ిքͷ‫ͱ )্( ౓ڧ‬ϕΫτϧ (Լ)ɻ(c) ࣓໘࣓քͷ‫ۉ‬ҰԽΛਤͬͨɻ͜ΕʹΑΓɼද໘࣓քͷϐʔքͷ‫ͱ )্( ౓ڧ‬ϕΫτϧ (Լ)ɻதԝͷࢼ‫ݧ‬ηϧʹϑΟʔΫ஋͕Լ͕ͬͨɻͦΕ͕ޭΛ૗͠ɼTD24*Ճ଎؅Ͱ͸ɼϧυ͕ूத͢ΔΑ͏ʹઃ‫͋ͯ͠ܭ‬Δɻ

100 MV/m Λ௒͑ΔՃ଎ੑೳΛୡ੒ͨ͠ɻ·ͨɼTD24*ͷඇ‫ݮ‬ਰ൛Ͱ͋Δ T24 Ͱ͸ɼ110ʙ120 MV/m ͷՃ଎͕͋ΔɻνϣʔΫϞʔυ‫ܕ‬Ճ଎؅ͷ։ൃ͸ਗ਼՚େֶ (தޯ഑Λग़ͤΔ͜ͱ͕Θ͔ͬͨɻ࠷৽൛Ͱ͋Δ TD26CC*ࠃ) ͷάϧʔϓ͕୲౰͓ͯ͠Γɼਤ 7 ʹࣔ͢Α͏ͳ୯η͸ɼ·ͩ౷‫͕ܭ‬গͳ͍͕ɼ100 MV/m ‫ڃ‬ͷੑೳΛ࣮‫ݱ‬ϧ‫ۭݧࢼܕ‬ಎΛ੡࡞ͯ͠ɼKEK ͷࢼ‫ࢪݧ‬ઃ (Nextef [9],͍ͯ͠ΔɻNew X-band Test Facility) Ͱߴిքࢼ‫ݧ‬Λߦͬͨ (2016͜Ε·Ͱड़΂͖ͯͨಋ೾؅‫ܕ‬ͷ‫ݮ‬ਰߏ଄ͷଞʹɼߴ࣍

ʙ2017 ೥)ɻॳ‫ظ‬ͷઃ‫Ͱܭ‬͸νϣʔΫߏ଄಺Ͱਂࠁͳ์

ϞʔυΛ‫ݮ‬ਰͤ͞Δߏ଄ͱͯ͠ɼSACLA ͷ C όϯυి͕ൃੜ͕ͨ͠ [10]ɼͦͷ‫ޙ‬ͷվྑͰ์ిͷ໰୊͸վળՃ଎؅Ͱ࠾༻͞Ε͍ͯΔνϣʔΫϞʔυ‫ܕ‬ͷ‫ݮ‬ਰߏ଄͞Εͨ [11]ɻ

͕͋Γ, X όϯυ൛ͷՃ଎؅ͷ։ൃ΋ਐΊΒΕ͍ͯΔɻ
νϣʔΫϞʔυ‫ܕ‬ͷ‫ݮ‬ਰߏ଄ͷར఺ͱͯ͠͸ɼ• σΟεΫΛટ൫͚ͩͰՃ޻Մೳ (ϛϦϯά͸ෆཁ)• ಋ೾؅‫ݮܕ‬ਰߏ଄Ͱ͸ɼਤ 6(a) ͷࢦ͞͠ՕॴͰද

໘࣓ք (ද໘ిྲྀ) ͷ૿େ͕͋Δ͕ɼνϣʔΫϞʔυ‫ܕ‬ͷ‫ݮ‬ਰߏ଄ʹ͸ɼද໘࣓քͷ૿େ͸ͳ͍ͱ͍͏͜ͱ͕‫͛ڍ‬ΒΕΔɻ‫ʹٯ‬ɼܽ఺ͱͯ͠͸ɼ• νϣʔΫߏ଄͕͋Δ͜ͱʹΑΓɼ‫ػ‬ցతʹऑ͍• νϣʔΫߏ଄͸ൺֱతෳࡶͳͷͰɼͦͷதͰͷ์ిΛආ͚Δͷ͕೉͍͠

4

KEK ʹ͓͚Δ‫ڀݚ‬

KEK ʹ͓͚Δৗ఻ಋ X όϯυՃ଎؅։ൃ͸ɼJapan
Linear Collider (JLC) ࣌୅ʹ࢝·ΓɼSLAC ͱͷ‫ڞ‬ಉ‫ݚ‬‫ڀ‬Λ௨ͯ͡ɼGLC ͷ࣌୅ʹ͸ 60 cm ؅ͷ੡࡞ɾࢼ‫Ͱ·ݧ‬Λߦ͍ͬͯͨɻ͔͠͠ɼͦͷ‫ޙ‬ɼੈք‫ڞ‬௨ͷϦχΞίϥΠ
μʔΛઃ‫͢ܭ‬Δಈ͖͕‫͜ى‬Γɼ2004 ೥ͷ International

Technology Recommendation Panel (ITRP) ʹΑΔ‫ק‬ࠂʹఴͬͯɼ௒఻ಋՃ଎Λ࣠ʹͨ͠ ILC ‫ܭ‬ը্ཱ͕͕ͪͬ
ͨɻ͜ͷ‫ʹࠂק‬ΑΓɼKEK Ͱৗ఻ಋՃ଎‫ڀݚ‬։ൃΛਐΊ͍ͯͨࢼ‫ࢪݧ‬ઃ Global Linear Collider Test Accelerator(GLCTA) ͕ղମ͞ΕΔ͜ͱʹͳͬͨɻ͜ͷ࣌ɼGLCTA• νϣʔΫߏ଄಺ʹి࣓ք͕ (গ͠) ೖΓࠐΉ෼ɼQ
஋͕௿͍ʹ͋ͬͨ X όϯυՃ଎؅։ൃͷͨΊͷࢿ‫ݯ‬Λ KEK Ճ

8 ͜Ε͕ϒϨʔΫμ΢ϯ཰ͱؔ܎͢Δ͔͸ɼࠓͷͱ͜ΖΘ͔͍ͬͯͱͳͬͯɼKEK ిࢠཅిࢠೖࣹ‫ث‬౩ͷՃ଎؅૊ཱࣨ΁ͳ͍ɻ଎‫ث‬ͷ෱ాໜथࢯɼං‫ޙ‬ᆹହࢯɼদຊमೋࢯ͕ͨͪத৺

6
173

Ҡઃ͠ɼNextef ͱͯ͠ੜ·ΕมΘͬͨ [12]ɻஸ౓ͦͷ

KEK Ͱಠࣗʹ։ൃɾ੡࡞ͨ͠ 4 ෼ׂํࣜͷಋ೾؅‫ݮܕ‬

ࠒɼCLIC ͷप೾਺͕ 30 GHz ͔Β X όϯυ (12 GHz)ਰۭಎͷࢼ‫ݧ‬Λߦͬͨɻ͜Εʹ͍ͭͯ͸ɼ࣍ͷୈ 4.2 અ΁Լ͕ͬͨ͜ͱ΋͋ΓɼCLIC ༻ϓϩτλΠϓՃ଎؅ΛͰղઆ͢Δɻ

Nextef Ͱࢼ‫͢ݧ‬Δ࿩͕ग़࢝ΊͨɻKEK ͸‫ͯ͠ͱߏػ‬CLIC ‫ܭ‬ըʹࢀՃ͍ͯ͠Δ༁Ͱ͸ͳ͍͕ɼCERN ͱͷ֮ॻ (ICA-JP-0103) ʹ‫ڞ͍ͨͮج‬ಉ‫ڀݚ‬Λ্ཱͪ͛ɼX όϯυߴిքՃ଎؅։ൃͷ‫ڀݚ‬ΛਐΊΔ͜ͱʹͳͬͨɻ

4.2

4 ෼ׂํࣜՃ଎؅։ൃ

Ճ଎؅͸ɼ͜Ε·Ͱड़΂͖ͯͨΑ͏ͳσΟεΫɾελοΫํࣜͰ੡࡞͞ΕΔ͜ͱ͕Ұൠత͕ͩɼ͜ͷୈ 4.2 અͰ

KEK / NextefԞি࠱ύ̵ᾯᾍṫᄄẂᾔᾷᾍέᾭὨώᾌᾱᾷ

͸ɼͦΕͱ͸ʮ௚ަʯ͢ΔϏʔϜ࣠ํ޲ʹ෼ׂͨ͠ύʔπΛ੡࡞ɾ઀߹͢Δํࣜʹؔ͢Δ։ൃͷ‫ݱ‬ঢ়Λ঺հ͢Δɻͦͷ੡࡞ํࣜ͸ɼ
ʮ4 ෼ׂํࣜʯ(ඇ‫ݮ‬ਰͷ৔߹͸ 2 ෼ׂํύ̵ᾯᾍṬᄄẂᾔᾷᾍέᾭὨώᾌᾱᾷࣜ) ͱ‫ݺ‬͹ΕΔ΋ͷͰɼਤ 9 ʹͦͷྫΛࣔ͢ɻ4 ෼ׂํࣜͷ࠷΋େ͖ͳར఺͸ɼՃ଎Ϟʔυి࣓քʹΑΔද໘ి
ྲྀ͕઀߹ՕॴΛ౉Δ͜ͱ͕ͳ͍͜ͱͰ͋Δ (ද໘ిྲྀ͸ϏʔϜ࣠ํ޲ʹྲྀΕΔͨΊ)ɻ·ͨɼσΟεΫɾελοΫύ̵ᾯᾍṬế‫ܒ‬ሺុᰱᄄỀύ̵ᾯᾍṫếՉᥫጢᫌᆃᄄỀਤ 8: KEK ʹ͓͚Δ X όϯυߴిքࢼ‫ࢪݧ‬ઃ NextefɻํࣜͰ͸ɼԿेຕ΋ͷσΟεΫΛ௒ਫ਼ີՃ޻͠ɼελοΫͯ͠઀߹͠ͳ͚Ε͹ͳΒͳ͍͕ɼ4 ෼ׂํࣜͰ͸ɼଟηϧΛϛϦϯάͰҰ‫ʹؾ‬Ճ޻Ͱ͖ɼͦͷ‫ޙ‬ͷ૊ཱ΋؆୯
Ͱ͋Δɻۙ೥ɼ௒ਫ਼ີϛϦϯάՃ޻ٕज़͕޲্ͨ͜͠ͱ
΋͋Γɼ4 ෼ׂํࣜΛ࠾༻͢Δ͜ͱͰɼσΟεΫɾελοΫํࣜͱൺ΂ɼՃ଎؅ͷ੡࡞ίετΛେ͖͘࡟‫ݮ‬ग़དྷΔ
͜ͱ͕‫ظ‬଴͞Ε͍ͯΔɻ

4.1

Nextefߴిքࢼ‫ࢪݧ‬ઃ Nextef ͷશମਤΛਤ 8 ʹࣔ͢ɻNextefʹ͸ 2 ͭͷࢼ‫ݧ‬ΤϦΞ (γʔϧυ A ͱγʔϧυ B) ͕͋Δɻγʔϧυ A ͸Ϛϧνηϧۭಎͷࢼ‫ݧ‬Λߦ͑Δ͚ͩ
ͷे෼ͳۭ͕ؒ͋ΔͷͰɼϓϩτλΠϓՃ଎؅ͷߴిքࢼ‫͍ͯ͠༻࢖ʹݧ‬Δɻ·ͨɼγʔϧυ B ͸ϓϩτλΠ
ϓՃ଎؅ͷࢼ‫ݧ‬Λߦ͏ʹ͸‫͍ڱ‬ͷͰɼ୯ηϧ‫ۭܕ‬ಎͷࢼ‫Ͳͳݧ‬Λ௨ͯ͠‫ૅج‬తͳߴిքࢼ‫ݧ‬Λߦ͍ͬͯΔɻࢼ‫ݧ‬ʹ࢖͏ϚΠΫϩ೾‫ݯ‬͸ɼGLC ༻ʹ։ൃͨ͠ 50 MW ‫ڃ‬

X όϯυ Periodic Permanent Magnet (PPM) ΫϥΠετϩϯΛ࢖͍ͬͯΔɻγʔϧυ A ͸ɼ2 ୆ͷΫϥΠετ
ϩϯͷग़ྗΛ߹੒͠ɼ࠷େͰ 100 MW ͷ RF ύϧεΛ‫څڙ‬ग़དྷΔɻ·ͨɼγʔϧυ B Ͱ࢖༻͢Δ୯ηϧ‫ۭܕ‬ਤ 9: 4 ෼ׂํࣜՃ଎؅ͷྫ (TD18− QUAD− KEK)ɻ4‫ݸ‬ͷ 4 ෼ׂ෦ͷͻͱͭΛऔΓআ͍ͨঢ়ଶɻૠೖਤ͸ 1 ‫ݸ‬ͷ 4 ෼ׂ෦ɻ

ಎΛఆࡏ೾ۭಎͱͯ͠ઃ‫͢ܭ‬Δ͜ͱͰɼ1 ୆ͷΫϥΠε
τϩϯͰ‫څڙ‬ग़དྷΔఔ౓ͷग़ྗͰࢼ‫ʹݧ‬ඞཁͳՃ଎ޯ഑
͕ಘΒΕΔΑ͏ʹ޻෉͍ͯ͠ΔɻKEK Ͱ͸ɼ2008 ೥͔Β 2009 ೥ʹ͔͚ͯɼ18 ηϧͷ
CLIC ϓϩτλΠϓՃ଎؅ (ಋ೾؅‫ݮܕ‬ਰߏ଄෇͖) Λ 4γʔϧυ A Ͱ͸ɼ͜Ε·Ͱ 9 ຊͷ CLIC ϓϩτλΠ

෼ׂํࣜͰ੡࡞ɾࢼ‫( ͨ͠ݧ‬ਤ 9 ʹ͋ΔՃ଎؅)ɻX όϓՃ଎؅ͷߴిքࢼ‫ݧ‬Λߦͬͨɻਤ 5 ʹ͋ΔՃ଎؅໊ΛϯυՃ଎؅͸ɼ௨ৗɼϒϨʔΫμ΢ϯ཰͸ผͱͯ͠ɼ‫ݮ‬9‫ͯݟ‬΋Θ͔ΔΑ͏ʹ ɼKEK / Nextef ͷ CLIC ϓϩτਰߏ଄෇͖ͷ৔߹Ͱ΋Ճ଎ޯ഑ 100 MV/m ·Ͱ͸ίϯλΠϓՃ଎؅։ൃ΁ͷߩ‫౓ݙ‬͸ߴ͍ɻσΟγϣχϯά͕ग़དྷΔɻ͔͠͠ɼ͜ͷ 4 ෼ׂํࣜՃ଎

Ұํɼγʔϧυ B ʹ͓͚Δ୯ηϧ‫ۭܕ‬ಎͷຊ֨తͳ؅͸ɼ60 MV/m ΑΓߴ͍Ճ଎ޯ഑ʹ౸ୡ͢Δ͜ͱ͢Βߴిքࢼ‫ݧ‬ͷ։࢝͸ɼγʔϧυ A ΑΓ΋৽͘͠ 2016 ೥ग़དྷͣɼ౰࣌ɼ࣮‫ݧ‬తʹͦͷ‫ݪ‬ҼΛಥ͖ࢭΊΔ͜ͱ΋ग़Ͱɼ࠷ॳʹߦͬͨͷ͸ɼୈ 3 અͷ࠷‫ʹޙ‬৮Εͨਗ਼՚େֶ

དྷͳ͔ͬͨɻ4 ෼ׂํࣜՃ଎؅ͷ։ൃ͸ɼ͜͜Ͱ͠͹Β੡ͷνϣʔΫϞʔυ‫ݮܕ‬ਰۭಎͷࢼ‫ͨͬ͋Ͱݧ‬ɻͦͷ‫ޙ‬ɼ͘ࢭ·͍͕ͬͯͨɼ2011 ೥ʹɼKEK ‫ػ‬ց޻ֶηϯλʔ

9 ҹ࡮෺Ͱ͸‫͍͘ʹݟ‬ͷͰɼWeb ্Ͱެ։͍ͯ͠Δ PDF ϑΝΠϧͰ֬ೝ͍͖͍ͯͨͩͨ͠ɻhttp://www.jahep.org/hepnews/(౰࣌) ͷ౦อஉࢯ͕΋͏Ұ౓ 4 ෼ׂํࣜʹ௅ઓ͠Α͏ͱ‫ض‬Λ༲͛ͨɻஶऀ͸ͦΕʹࢍಉ͠ɼಠࣗͷγϛϡϨʔ7
174

SD1_QUAD-R04G01_K1, 100+150 ns
Breakdown Rate [/pulse/m]

(b)

(a)
ỘԋԸᦼỞ
ỘԋԸᦼở
ࡂᇎ

ৄ࡮ὲᾧᾇᾛ
(Feb. 27 to 1:50am Mar. 5, 2017
1:50am Mar. 5 to Mar. 10, 2017-410‫ݸ‬἞ἻṼ᭼‫ג‬Ὓ
(8㽢

30

-5

∝

10

8㽢

ਤ 10: KEK/Nextef Ͱߴిքࢼ‫ ͨ͠ݧ‬4 ෼ׂํࣜ X ό-610ϯυՃ଎ߏ଄ͷΞΠϦε෇ۙͷࣸਅɻ(a) ॳ‫ظ‬ͷ 4 ෼ׂ

CLIC specification

ํࣜ (TD18− QUAD− KEK)ɻࣸਅʹ͋ΔΞΠϦε‫ܘ‬ɿ-75.3 mmɻ(b) վྑ 4 ෼ׂํࣜ (SD1− QUAD-R04G01)ɻ

10

ࣸਅ͋ΔΞΠϦε‫ܘ‬ɿ8.4 mmɻ

100

110

120

Eacc [MV/m]

(b)

(a)

c

E ac

ਤ 12: վྑ 4 ෼ׂํࣜͷ୯ηϧ‫ݮܕ‬ਰۭಎͷϒϨʔΫμ΢ϯ཰ͷଌఆ݁ՌɻEacc ͸ɼՃ଎ޯ഑Λද͢ɻଌఆ
‫ޙؒظ‬൒͸ɼ110 MV/m ҎԼͷՃ଎ޯ഑Ͱ͸ϒϨʔΫμ΢ϯ͸·ͬͨ͘ൃੜ͠ͳ͔ͬͨͷͰɼͦͷ‫ؒظ‬தʹϒϨʔΫμ΢ϯ͕ 2 ճൃੜͨ࣌͠ͷ஋Λ্‫ͯࣔͯ͠͠ͱݶ‬͋Δɻਤ 11: Nextef/γʔϧυ B Ͱߴిքࢼ‫ͨ͠ݧ‬վྑ 4 ෼ׂ

CLIC ͷ࢓༷Λຬͨ͢‫ࠐݟ‬Έ͕͋Δ͜ͱ͕෼͔ͬͨɻࢼ

ํࣜͷ୯ηϧ‫ݮܕ‬ਰۭಎɻ(a) ௒ਫ਼ີϛϦϯάՃ޻Ͱ੡‫ݶ͕ؒظݧ‬ΒΕ͍ͯͨͨΊɼ͜͜Ͱ͸ࢼ‫ݧ‬ͷ࠷‫ޙ‬ͷ‫ؒظ‬

࡞ͨ͠ 4 ෼ׂ෦ͷͻͱͭɻRF ઃ‫ܭ‬͸ஶऀ͕ɼ‫ػ‬ցઃ‫ܭ‬ͰͷϒϨʔΫμ΢ϯ཰Λ࢖ۭͬͯಎͷੑೳΛධՁ͕ͨ͠ɼ

͸ KEK ‫ػ‬ց޻ֶηϯλʔͷߴ෋ ढ़࿨ ࢯ͕ߦͬͨɻ(b)͜ͷࢼ‫ݧ‬தɼ࠷‫Ͱ·ޙ‬ϒϨʔΫμ΢ϯ཰͸ண࣮ʹԼ͕ͬ

4 ෼ׂ෦ 4 ‫ݸ‬ΛిࢠϏʔϜ༹઀Ͱ઀߹ͨ͠௚‫ޙ‬ɻ͍ͯͬͨ͜ͱΛߟ͑Δͱɼ͞ΒʹίϯσΟγϣχϯάΛ
ਐΊΕ͹ɼϒϨʔΫμ΢ϯ཰͕͞Βʹ௿͘ͳΔՄೳੑ͕γϣϯ‫[ ڀݚ‬13] ͳͲʹ‫͍ͯͮج‬ɼैདྷͷ 4 ෼ׂํࣜʹͭ͋ͬͨ͜ͱΛࢦఠ͓ͯ͘͠ɻҎ্ʹΑΓɼ৽͍̐͠෼ׂ

͍ͯߟ͑ΒΕΔ͢΂ͯͷܽ఺Λࠀ෰͢Δʰվྑ 4 ෼ׂํํࣜͷޮՌͱՄೳੑΛ֬ೝ͢Δ͜ͱ͕Ͱ͖ͨ [16]ɻ
‫ࡏݱ‬ɼ24 ηϧ͔Β੒Δ CLIC ϓϩτλΠϓՃ଎؅ࣜʱΛߟҊͨ͠ [14]ɻ۩ମతͳվྑ఺͸ɼਤ 10 ʹࣔͯ͋͠ΔΑ͏ʹɼ(TD24*ɼਐߦ೾) Λվྑ 4 ෼ׂํࣜͰ੡࡞தͰɼ2018೥౓தʹߴిքࢼ‫ݧ‬Λߦ͏༧ఆͰ͋Δɻ• ϑΟʔϧυ૿େΛ཈͑ΔͨΊͷେ͖ͳ R ໘औΓ
(0.4 mm)• 4 ෼ׂ෦͕ີண͢Δ৔߹ʹൃੜ͢Δ‫ڪ‬Εͷ͋ΔԾ૝ϦʔΫΛͳ͘͢ඍখΪϟοϓ (0.1 mm)

5

SLAC ʹ͓͚Δ‫ڀݚ‬Ͱ͋Δɻ͜ͷ৽͍͠ํࣜͷޮՌΛௐ΂ΔͨΊɼൺֱతࢼSLAC ʹ΋ɼNextef ʹ૬౰͢Δߴిքࢼ‫ࢪݧ‬ઃ ASTA
(Accelerator Structure Test Area) ͕͋Δɻͦ͜Ͱ͸ɼ50‫ݧ‬਱ߦͷ༰қͳ୯ηϧ‫ݮܕ‬ਰۭಎΛվྑ̐෼ׂํࣜͰ੡

‫ݸ‬Ҏ্ͷ X όϯυՃ଎ߏ଄ (͓΋ʹɼ୯ηϧ‫ )ܕ‬Λࢼ‫ݧ‬࡞ͨ͠ [15](ਤ 11)ɻ͜͜Ͱɼ4 ෼ׂ෦ͷ઀߹ʹ͸ɼిࢠ͖ͯͨ͠ɻͦ͜Ͱͷࢼ‫݁ݧ‬Ռ͸ɼʮද໘࣓քޮՌͷॏཁੑϏʔϜ༹઀Λ࢖ͬͨɻ͜Ε͕ X όϯυՃ଎ߏ଄ࣗମΛͷൃ‫ݟ‬ʯʹେ͖͘ߩ‫ͨ͠ݙ‬ɻຊઅͰ͸ɼ࠷ۙͷ੒Ռͱ͠ిࢠϏʔϜ༹઀Ͱ૊Έཱͯɼ໰୊͕ͳ͍ߴిքੑೳ͕ग़

ͯɼৗ఻ಋ௿Թۭಎࢼ‫ݧ‬Λ঺հ͢Δ [17]ɻASTA ʹ͓͍ͨ࠷ॳͷྫͱͳͬͨɻ

ͯɼਤ 13 ʹ͋ΔΫϥΠΦελοτ಺ʹ୯ηϧ‫ܕ‬ඇ‫ݮ‬ਰஶऀୡ͸ɼKEK/Nextef ࢪઃʹͯɼվྑ 4 ෼ׂํࣜͷ୯ηϧ‫ݮܕ‬ਰۭಎ (ఆࡏ೾) ͷߴిքࢼ‫ݧ‬Λߦ͍ɼ໨ඪ
ͷ 100 MV/m Λେ্͖͘ճΔ 120 MV/m ௒ͷՃ଎ޯ
഑·Ͱ RF ίϯσΟγϣχϯάΛߦ͏͜ͱʹ੒ޭͨ͠ɻ
ਤ 12 ʹɼRF ίϯσΟγϣχϯά‫ͨͬߦʹޙ‬ϒϨʔΫμ΢ϯ཰ͷଌఆ݁ՌΛࣔ͢ɻࣜ (1) Ͱεέʔϧ͢ΔͱɼۭಎΛೖΕɼ45 K ʹͯߴిքࢼ‫ݧ‬Λߦͬͨɻ݁ՌΛਤ

14 ʹࣔ͢ (Cu@45K)ɻࣨԹʹ͓͚Δࢼ‫݁ݧ‬Ռ (Soft Cu,
Hard Cu, Hard CuAg) ͱൺ΂Δͱɼ45K ͷ௿ԹͰ͸֨ஈʹߴ͍Ճ଎ੑೳ͕ग़ͨɻ͜Ε͸ɼಔͷߗ౓ʹؔ܎ͯ͠
͍Δͱߟ͑ΕΒ͍ͯΔɻͦ΋ͦ΋ɼϒϨʔΫμ΢ϯ཰ͷՃ଎ޯ഑ґଘੑ (ਤ 14 ʹ͋Δ܏͖ʀ͜͜Ͱ͸୯ʹʮ܏

8175

͖ʯͱ‫ )͏ݴ‬͸ɼϒϨʔΫμ΢ϯͷ෺ཧʹؔ܎͍ͯ͠Δɻ
Ζ͏෇͚ͳͲͷߴԹॲཧΛͯ͠ಷͬͨೈಔ (Soft Cu) ΑϒϨʔΫμ΢ϯɾτϦΨʔ‫ߏػ‬ͷղ

6

໌‫ڀݚ‬

Γ΋ম͖ಷ͠ͷͳ͍ߗಔ (Hard Cu) ͷํ͕܏͖͸‫Ͱٸ‬
͋ΔɻಔʹۜΛগྔࠞͥͨ߹ۚ͸͞Βʹߗ͘ͳΔ͜ͱ͕஌ΒΕ͓ͯΓɼ܏͖͸͞Βʹ‫͋Ͱٸ‬ΔɻࡐྉͰ͋Δಔͷߗ౓͕ϒϨʔΫμ΢ϯͷ෺ཧʹӨ‫͍ͯ͠ڹ‬Δͱ͍͑Δɻ
ͦͯ͠ɼ௿Թʹ͢Δ͜ͱͰ࠷΋ߗ͘ͳΓɼ͜Ε·Ͱͷৗ఻ಋՃ଎ߏ଄ͷதͰ࠷ߴͷՃ଎ੑೳΛࣔͨ͠ɻ45K ʹ͓͚Δ܏͖͕ಔ߹ۚͷ΋ͷͱಉఔ౓ɼ·ͨ͸ɼͦΕΑΓ‫͋Ͱ͖܏ͳٸ‬ΔͱԾఆ͢Δͱɼ45K ʹ͓͚Δࢼ‫݁ݧ‬Ռ͸ɼCLIC ͷ࢓༷ʹରͯ͠ɼ200 MV/m Λ௒͑ΔՃ଎ޯ഑ʹ૬౰͢Δɻࡐྉͷߗ౓ͱϒϨʔΫμ΢ϯ཰ͱͷؔ܎
͸·ͩԾઆͰ͋Δ͕ɼ‫ࡏݱ‬ɼϑϧνϣʔΫϞʔυ‫ۭܕ‬ಎ[18] ͱ‫ݺ‬͹ΕΔಛघͳ୯ηϧ‫ۭݧࢼܕ‬ಎͱߴग़ྗύϧεϨʔβʔΛ࢖ͬͯɼͦͷԾઆͷ‫ূݕ‬Λ೔ถ‫͓( ྗڠ‬΋ʹɼৗ఻ಋՃ଎ߏ଄ͷϒϨʔΫμ΢ϯ͸ɼͦͷ಺෦Ͱൃੜ
͢Δਅۭ์ిʹΑͬͯ‫͜ى‬Δɻ͔͠͠ɼͦͷਅۭ์ి͕
ͲͷΑ͏ͳϝΧχζϜͰҾ͖‫͜͞ى‬ΕΔ͔ʹ͍ͭͯ͸ɼະͩղ໌͞Ε͍ͯͳ͍ɻͭ·ΓɼϒϨʔΫμ΢ϯΛҾ͖‫࢓͢͜ى‬૊Έ (ϒϨʔΫμ΢ϯɾτϦΨʔ‫ )ߏػ‬Λղ໌͢Δ͜ͱͰɼৗ఻ಋߴిքՃ଎ੑೳΛ֨ஈʹҾ্͖͛Δ
͜ͱ͕ՄೳʹͳΔ͔΋஌Εͳ͍ɻ‫ࡏݱ‬ɼCLIC ‫ܭ‬ը͕͋Δ͜ͱ΋͋Γɼ༷ʑͳϒϨʔΫμ΢ϯɾτϦΨʔ‫ߏػ‬ͷղ໌‫ߦ͕ڀݚ‬ΘΕ͓ͯΓɼຊઅͰ͸ɼͦͷ͍͔ͭ͘Λ঺
հ͢Δɻ

6.1

SLAC-KEK) Ͱߦ͍ͬͯΔɻཧ࿦త‫ڀݚ‬ϒϨʔΫμ΢ϯ͸ɼϛΫϩͳεέʔϧͷ‫ݱ‬৅͔ΒൃੜCold Head͢Δͱߟ͑ΒΕɼ‫׬‬શͳཧղͷͨΊʹ͸ɼ‫ࢠݪ‬ɾ෼ࢠϨ

Dark-Current
MonitorϕϧͰߟ͑Δඞཁ͕͋Δɻͦ͜ͰɼϔϧγϯΩେֶ (ϑΟϯϥϯυ) ͷཧ࿦άϧʔϓ͸ɼਤ 15 ʹࣔ͢Α͏ͳϚϧ

Brazed-in Metal
tal
Foil

νεέʔϧͷγϛϡϨʔγϣϯΛ։ൃ͍ͯ͠Δɻ෼ࢠಈ

Acceleratingg
Structurereྗֶ΍ӡಈֶతϞϯςΧϧϩͳͲͷख๏Λ࢖ͬͯୈҰ‫ݪ‬

RF Flange withith
Crashed Metal
etall
GasketΔɻ‫Ͱ఺࣌ݱ‬͸ɼ‫ػࢉܭ‬ͷೳྗʹ‫ݶ‬ք͕͋ΓɼDC ์ిཧͰϒϨʔΫμ΢ϯΛཧղ͠Α͏ͱ͢Δ໺৺తࢼΈͰ͋ʹؔͯ͠ͷΈγϛϡϨʔγϣϯ͕ՄೳͰ͋Δ͕ɼಔද໘

Stainless SteelTM01 WaveguideʹφϊϝʔτϧɾαΠζͷಥ‫͕͋ى‬Γɼͦ͜ʹߴ͍ిք͕͔͔ͬͨ৔߹ɼͲͷΑ͏ͳ৚͕݅ͦΖ͑͹ਅۭ์ిʹ

Cryostat Assemblyਤ 13: ৗ఻ಋ௿Թࢼ‫༻ݧ‬ΫϥΠΦελοτɻSLAC ఏ‫ڙ‬ɻࢸΔ͔Λৄࡉʹௐ΂Δ͜ͱ͕Մೳͱͳ͍ͬͯΔɻৄ͘͠BreakdownProbability 1 pulse meter͸ɼ͜ͷ‫ڀݚ‬Λ౷‫͍ׅͯ͠‬Δ Flyura Djurabekova ࢯ (ϔϧγϯΩେֶ) ͷൃදεϥΠυ [19] Λࢀর͍͖͍ͨͩͨɻ

100·ͨɼ͜ͷଞʹ΋ଟ͘ͷཧ࿦త‫͕͋ڀݚ‬Γɼؔ࿈ϫʔΫ

10 1
10 2
10 3
10

4

10

5

So t Cu
Hard Cu
Hard
CuAg 1

10 6
10 7
50

γϣοϓ [20] ͳͲͰৄ͍͠৘ใΛಘΔ͜ͱ͕ग़དྷΔɻ

Cu
Hard CuAg

CLIC specification

100

150

200
250
Gradient MV m

300

350

ਤ 14: SLAC / ASTA ͰߦΘΕͨߴిքࢼ‫ݧ‬ͷ݁Ռ [17]ɻ

45K ʹ͓͚Δ௿Թࢼ‫ݧ‬ͷ݁Ռ (Cu@45K) ͷଞɼೈಔ (SoftCu)ɼߗಔ (Hard Cu)ɼಔͱۜͷ߹ۚ (Hard CuAg) ͔Β੡࡞ͨ͠୯ηϧ‫ܕ‬ඇ‫ݮ‬ਰۭಎʹର͢ΔৗԹͰͷࢼ‫݁ݧ‬Ռ΋ࣔͯ͋͠ΔɻRF ઃ‫ۭ( ܭ‬ಎͷ‫ز‬Կֶత‫ܗ‬ঢ়) ͸͢΂ͯಉ͡Ͱ͋Δɻਤ 15: ϔϧγϯΩେֶ (ϑΟϯϥϯυ) ͷཧ࿦άϧʔϓ͕։ൃ͍ͯ͠ΔɼϒϨʔΫμ΢ϯͷϚϧνεέʔϧɾγ
ϛϡϨʔγϣϯͷશମ૾ɻϔϧγϯΩେֶఏ‫ڙ‬ɻ

9
176

6.2

࣮‫ݧ‬త‫ڀݚ‬ϒϨʔΫμ΢ϯͷ࣮‫ݧ‬త‫ڀݚ‬͸ɼՃ଎ߏ଄ͳͲͷߴిքࢼ‫ʹݧ‬ΑΓߦΘΕΔɻͦ͜Ͱ͸ɼϒϨʔΫμ΢ϯʹ
൐ͬͯൃੜ͢Δ൓ࣹ೾ɼిྲྀϑϥογϡɼX ઢɼޫɼԻ
‫Ͳͳࣹ์ڹ‬Λ‫؍‬ଌ͠ɼՃ଎ޯ഑΍ RF ύϧε෯ͳͲͱͷ૬ؔΛௐ΂Δɻ·ͨɼߴిքࢼ‫͕ݧ‬ऴྃͨ͠Ճ଎؅Λ੾ͬͯɼ಺෦Λ SEM ͳͲͰ‫͢࡯؍‬Δɻ͔͠͠ɼզʑ͕
࠷΋஌Γ͍ͨͷ͸ɼϒϨʔΫμ΢ϯͷτϦΨʔ (‫Ͱ )ݯ‬͋Δɻ্‫؍ه‬ଌྔ΍ SEM ‫࡯؍‬ͷ݁Ռ͸ɼͲΕ΋ϒϨʔΫμ΢ϯͷ݁Ռൃੜ͢Δ 2 ࣍తͳ΋ͷͰ͋ΓɼϒϨʔΫμ΢ϯɾτϦΨʔΛಥ͖ࢭΊΔʹ͸ԕճΓͰ͋Δͱ͍͏
ߟ͑΋͋Δɻͦ͜Ͱۙ೥ɼߴిքࢼ‫ݧ‬ͷࢼ‫ݧ‬ମ಺෦Λ௚઀‫͠࡯؍‬ɼϒϨʔΫμ΢ϯͷॠؒલ‫ޙ‬Λࢹ֮తʹͱΒ͑Δ࣮‫ߦ͕ݧ‬ΘΕ͍ͯΔɻ
ʮඦฉ͸Ұ‫͔ͣ͠ʹݟ‬ʯͰ͋Δɻ

6.2.1

DC ์ి࣮‫͚͓ʹݧ‬Δ௚઀‫࡯؍‬੢҆ަ௨େֶ (தࠃ) ͷ‫ڀݚ‬άϧʔϓ͸ɼਅۭதͷి‫( ۃ‬Ϊϟοϓɿ0.5∼5 mm) ʹ਺े kV ͷ DC ߴిѹΛ͔͚ͯɼ௚઀‫ݧ࣮࡯؍‬Λߦ͍ͬͯΔɻਤ 16 ͸ɼߴ଎౓ΧϝϥͰϒϨʔΫμ΢ϯͷॠؒલ‫ޙ‬ΛͱΒ͑ͨྫͰ͋Δɻ্ଆʹಔ੡ͷಥ‫ى‬ঢ়Χιʔυ (ϚΠφεి‫͕͋ )ۃ‬ΓɼԼଆʹಔͷฏ൘ͷΞϊʔυ (ϓϥεి‫͕͋ )ۃ‬ΔɻϒϨʔΫμ΢ϯΛ‫ݕ‬ग़ͨ͠ॠؒ (∆t = 0)ɼΧιʔυ্Ͱখ͞ͳൃޫ͕࢝·Γɼͦͷ‫∆( ޙ‬t = 200 ns)ɼΞϊʔυଆͷൃޫ͕։࢝ɾ֦େ͢Δͷ͕‫ݟ‬ΒΕΔ10 ɻ͜Ε͸ɼΧιʔυ্ʹτϦΨʔ͕͋ΓɼΧιʔυ͔ΒΞϊʔυʹ޲͔ͬͯྲྀΕͨిࢠ͕Ξϊʔυʹিಥͨ݁͠ՌɼΞϊʔυ͕೤ͤΒΕͯൃޫͨ͠ͱཧղग़དྷΔɻ͜ͷ࣮‫݁ݧ‬Ռ͸ɼ্‫ه‬ϔϧγϯΩେֶͷγϛϡϨʔγϣϯͷΑ͍Πϯϓοτͱ
ͳΔɻཧ࿦ɾ࣮‫ݧ‬૒ํͷࠓ‫ޙ‬ͷల։͕‫ظ‬଴͞ΕΔɻਤ 16: DC ϒϨʔΫμ΢ϯͷॠؒલ‫ޙ‬Λߴ଎౓ΧϝϥͰࡱӨͨ͠ྫɻ্ଆʹಔ੡Χιʔυͷಥ‫( ى‬ϚΠφεి‫)ۃ‬ɼԼଆʹΞϊʔυͷಔฏ൘ (ϓϥεి‫͕͋ )ۃ‬ΔɻࠃࡍϫʔΫγϣοϓ MeVArc2017 [20] ʹ͓͚Δ Zhenxing Wangࢯ (தࠃɾ੢҆ަ௨େֶ) ͷൃදεϥΠυΑΓൈਮɻ͢Α͏ʹɼ3 ୆ͷ TV ΧϝϥʹΑΔηοτΞοϓΛߏஙͨ͠ɻࢼ‫ݧ‬։࢝౰ॳɼRF ϒϨʔΫμ΢ϯͷॠؒʹ͸ɼҴ࠺ͷΑ͏ͳܹ͍͠ࣄ৅͕‫ͨͬ͜ى‬ɻ͔͠͠ɼ͜ͷΑ͏ͳࣄ৅͸ɼࢼ‫ݧ‬ͷ࠷ॳ͚ͩͰɼRF ίϯσΟγϣχϯά͕ਐΉͱ‫ݟ‬ΒΕͳ͘ͳͬͨɻ‫؍‬ଌ͞Εͨ߹‫ ܭ‬205 ճͷϒϨʔΫμ΢ϯࣄ৅Λ౷‫ܭ‬తʹղੳͯ͠Έͯ΋ɼϒϨʔΫμ΢ϯͷॠؒʹՃ଎ۭಎ಺ͰՐՖ΍Ҵ࠺ͷΑ͏ͳ೿खͳࣄ
৅͕‫ͨͬ͜ى‬ͷ͸શମͷ͏ͪ໿ 10%ͱগͳ͘ɼ‫ͨͬ͜ى‬ͷ΋ RF ίϯσΟγϣχϯάͷॳ‫ͨͬ͋Ͱ͚ͩظ‬ɻ࠷΋ଟ͔ͬͨࣄ৅͸ɼϒϨʔΫμ΢ϯͷॠؒɼి‫ʹۃ‬૬౰͢
Δۭಎ୺൘্Ͱಥવখ͞ͳരൃ͕‫͜ى‬Δʮεϙοτ‫ܕ‬രൃʯͰɼ͜Ε͸શମͷ໿ 40%͋ͬͨɻਤ 18 ʹͦͷҰྫΛࣔ͢ɻ࣍ʹଟ͔ͬͨͷ͸ɼେిྗࢼ‫ݧ‬தʹ҆ఆతʹൃޫ͍ͯͨ͠୺൘্ͷʮً఺ʯ͕ɼϒϨʔΫμ΢ϯͷॠؒʹരൃɾফ໓ͨ͠ࣄ৅Ͱɼ͜Ε͸શମͷ໿ 25%͋ͬͨɻਤ 19 ʹͦͷҰྫΛࣔ͢ɻً఺ͷଘࡏ͸ੲ͔Β஌ΒΕͯ

6.2.2

509 MHz ࿈ଓ೾ۭಎࢼ‫͚͓ʹݧ‬Δ௚઀‫࡯؍‬RF ϒϨʔΫμ΢ϯͷτϦΨʔ‫ߏػ‬ղ໌ͷεςοϓͱͯ͠ɼ্‫ه‬ͷཧ࿦΍࣮‫ͨࣔ͠Ͱݧ‬Α͏ͳ DC ϒϨʔΫμ΢ϯͷཧղ͸ॏཁͰ͋Δ͕ɼৗ఻ಋՃ଎ʹ͸ϚΠΫϩ೾͍͕ͨɼͦΕ͕ϒϨʔΫμ΢ϯͷ‫ݯ‬ͷͻͱͭͰ͋Δ͜ͱ͸ɼࠓճͷ‫؍‬ଌͰॳΊͯ൑໌ͨ͠ɻৄ͘͠͸ɼKEK Ճ଎‫ࢪڀݚث‬ઃτϐοΫε (Web ‫[)ࣄه‬22] ΍‫ݪ‬ஶ࿦จ [23]Λࢀߟʹ͍͖͍ͯͨͩͨ͠ɻ

Λ࢖͏ͷͰɼ࠷ऴతʹ͸ RF ϒϨʔΫμ΢ϯΛ‫͚ͳݟ‬ΕЈЊқӑәϦ

Չᥫክູ‫״‬ᤃ۶᱔ؔຩҸՆᎺ‫ڢװ‬͹ͳΒͳ͍ɻஶऀ͸ɼSuperKEKB ͷཅిࢠμϯϐϯά

ՉᥫክູЈЊқӑәϧ

Ϧϯά༻ͷ 509 MHz ৗ఻ಋߴप೾Ճ଎ۭಎ (࿈ଓ೾) ͷ։ൃɾ੡଄ʹ‫ܞ‬Θ͖͕ͬͯͨ [21]ɼ͜ͷୈ 6.2.2 અͰ͸ɼஶऀ͕ఏҊ͠ɼͦͷ࣮‫ ػ‬2 ߸‫ػ‬ͷ RF ίϯσΟγϣχϯ

௿͍͕ɼ࿈ଓ೾Ͱ͋ΔͨΊɼՃ଎ۭಎʹ͸େ͖ͳෛՙ͕
͔͔Δ͜ͱʹͳΔɻۭಎ಺Λ‫͢࡯؍‬ΔͨΊɼਤ 17 ʹࣔ
10 ͜Ε΋ҹ࡮൛Ͱ͸‫͍͘ʹݟ‬ͷͰɼWeb ্Ͱެ։͍ͯ͠Δ PDF

ϑΝΠϧΛࢀর͍͖͍ͨͩͨɻhttp://www.jahep.org/hepnews/ᾗ̵ᾤᾡ̵ᾌ

(a)(150mm)᪜ếͣ໇ѥỀЈЊқӑәϥÅ ክູዟೃἿ᜖᭼ếͣ໇ѥỀͰͷՃ଎ޯ഑͸਺ MV/m ఔ౓ͱύϧεӡసͱൺ΂Δͱ

᪜
ế͢໇ѥỀ

᪜
ế͢໇ѥỀ

Å ክູዟೃἿ᜖᭼ế͢໇ѥỀάʹ‫د‬ੜ͢Δ‫ͨͬߦͰܗ‬௚઀‫ݧ࣮࡯؍‬Λ঺հ͢Δɻͦ͜

᪜
ếͣ໇ѥỀ

(b)

ਤ 17: 509 MHz ࿈ଓ೾ۭಎͷ௚઀‫͚͓ʹݧ࣮࡯؍‬Δ 3
୆ͷ TV ΧϝϥͷηοτΞοϓਤɻ

10
177

7

͓ΘΓʹ
ITRP ʹΑΔ‫ࠂק‬Ҏ߱ɼද໘࣓քޮՌͷॏཁੑͷൃ

100 MV/m ‫ͱ΁ڃ‬ɼৗ఻ಋߴిքՃ଎‫ڀݚ‬͸ண࣮ͳਐẅϐ੓֢ϫẇ

࣮ΓɼGLC ࣌୅ͷՃ଎ޯ഑ 65 MV/m ͔Β CLIC ͷ଱Ҹ‫ۈ‬ӈἿᤔॄ‫ݟ‬΍ɼCLIC ‫ܭ‬ըΛத৺ͱͨ͠ࠃࡍ‫ڞ‬ಉ‫ڀݚ‬ͷ౒ྗ͕Ṓẋṓ ክູᾚᾰ̵έᾄὪᾷἿ
ṒẌṓΏክູᾚᾰ̵έᾄὪᾷἿ
ṒẍṓΏክູᾚᾰ̵έᾄὪᾷἿᇢ᫐
Ṝᾙᾰ̵ᾤԪếṝṚԋἿṜቷԪỀṛᾙᾰ̵ᾤԪếṝṚԋἿṛቷԪỀาΛ਱͍͛ͯΔɻ͞ΒͳΔඈ༂ͷϙςϯγϟϧͱͯ͠ɼνϣʔΫϞʔυ‫ݮܕ‬ਰߏ଄ɼߗ͍ಔ߹ۚࡐྉͷ࢖༻ɼ৽ష᫐ ẅቷẇ

͍͠੡࡞ํࣜ (4 ෼ׂํࣜ) ͳͲ͕͋Δɻਤ 18: ϒϨʔΫμ΢ϯͷॠؒͱͦͷ௚લͷεφοϓγϣοSLAC ͷৗ఻ಋ௿Թۭಎࢼ‫ݧ‬ͷ݁Ռ͸ɼCLIC ࢓༷ͷτ (ਤ 17 ͷ TV Χϝϥ 3 ͰࡱӨ)ɻ͜ͷྫͰ͸ɼϒϨʔϒϨʔΫμ΢ϯ཰ʹͯɼՃ଎ޯ഑ 200 MV/m Λ௒͑Δ

Ϋμ΢ϯͷॠؒɼۭಎ୺൘্Ͱεϙοτ‫ܕ‬രൃΛ‫؍‬ଌ͠ߴిքՃ଎͕ՄೳͰ͋Δ͜ͱΛ࣮‫ݧ‬తʹ͍ࣔࠦͯ͠Δɻ

ͨɻૠೖਤ͸ɼരൃՕॴͷ֦େਤɻԼͷϓϩοτ͸ɼૠϒϨʔΫμ΢ϯɾτϦΨʔ‫ߏػ‬ͷղ໌͕ਐΈɼࣨԹͰͦ

ೖਤ಺ͷً౓ͷมԽɻͷੑೳΛୡ੒ग़དྷΕ͹ɼILC ͷ 7 ഒఔ౓ͷՃ଎ޯ഑Λ࣋ͭϦχΞίϥΠμʔͷ࣮‫ݱ‬Մೳੑ͕‫ͯ͑ݟ‬དྷΔͱ͍͏ҙຯͰɼେ͖ͳΠϯύΫτ͕͋Δɻ
ຊߘͰ঺հग़དྷͳ͔ͬͨؔ࿈‫ڀݚ‬͸਺ଟ͋͘Δɻ࠷‫ޙ‬ʹɼ͜ͷ‫ڀݚ‬෼໺ʹ͓͚ΔओͳձٞΛ঺հ͢ΔͷͰɼ‫ڵ‬ຯͷ͋Δํ͸ɼࢀߟʹ͍͖͍ͯͨͩͨ͠ɻ

ẅϐ੓֢ϫẇ

଱Ҹ‫ۈ‬ӈἿᤔॄṒẌṓΏክູᾚᾰ̵έᾄὪᾷἿṒẋṓ ክູᾚᾰ̵έᾄὪᾷἿ
ክູᾚᾰ̵έᾄὪᾷἿ
ṒẋṓṒẌṓΏክູᾚᾰ̵έᾄὪᾷἿᇢ᫐ ṒẍṓΏክູᾚᾰ̵έᾄὪᾷἜ὚Ἷুख
ṛᾙᾰ̵ᾤԪếṝṚԋἿṛቷԪỀṜᾙᾰ̵ᾤԪếṝṚԋἿṜቷԪỀổᾙᾰ̵ᾤԪếṝṚԋἿṛቷԪỀᆷ঵ếክູ᭐ۜẮṚṘṣṟΏṷẀỀ• ʮCLIC ϫʔΫγϣοϓʯຖ೥ CERN ͰߦΘΕ͍ͯΔ CLIC ‫ܭ‬ըશൠ (Ճ଎‫ث‬ɼଌఆ‫ث‬ɼ෺ཧ) ʹؔ͢ΔϫʔΫγϣοϓɻલճ͸ɼ2018 ೥݄ 1 ݄ʹ։࠵͞Εͨ [25]ɻ

ష᫐ ẅቷẇ

ਤ 19: ϒϨʔΫμ΢ϯͷॠؒલ‫ޙ‬ͷεφοϓγϣοτ

• ʮInternational Workshop on Breakdown Science(ਤ 17 ͷ TV Χϝϥ 3 ͰࡱӨ)ɻ͜ͷྫͰ͸ɼେిྗࢼ

and High Gradient Technologyʯ‫ݧ‬தʹۭಎ୺൘্Ͱ҆ఆతʹൃޫً͍ͯͨ͠఺ͷҰ͕ͭৗ఻ಋߴిքՃ଎ʹؔ͢ΔࠃࡍϫʔΫγϣοϓͰ͋(௒৽੕രൃͷ೗͘ʹ) രൃ˰ফ໓͠ɼͦͷॠؒɼՃ଎ۭ

Δɻ2012 ೥·Ͱ͸ CERN, KEK, SLAC ͷ࣋ͪճΓಎ͕ϒϨʔΫμ΢ϯͨ͠ɻૠೖਤ͸ɼരൃًͨ͠఺ͷ৔Ͱ։࠵͠ɼ2013 ೥Ҏ߱͸ଞͷ‫ؔػڀݚ‬΍େֶͰ։࠵

ॴͷ֦େਤɻԼͷϓϩοτ͸ɼૠೖਤ಺ͷً౓ͷมԽɻ͞Ε͍ͯΔɻୈ 1 ճ͸ɼ2007 ೥ʹ CERN Ͱ։࠵͞Εɼͦͷ࣌ͷձ໊ٞ͸ʮThe X-Band Accelerating͜ͷୈ 6.2.2 અͰ঺հͨ͠‫ڀݚ‬͸ɼ509 MHzɾ࿈ଓ೾

Structure Design and Test-Program WorkshopʯͰͷՃ଎ۭಎʹؔ͢Δ΋ͷͰ͋Γɼৗ఻ಋߴిքՃ଎ߏ଄

͕͋ͬͨɼ2012 ೥ʹ KEK Ͱ։࠵ͨ͠ࡍʹɼ্‫ه‬(ΑΓߴ͍प೾਺Ͱύϧεӡస) ʹ͓͚ΔϒϨʔΫμ΢ͷձ໊ٞͱͳͬͨ (ං‫ࢯޙ‬ͷ໋໊)ɻஶऀ͕ 2015 ೥ϯͷϝΧχζϜͱಉ͔͡Ͳ͏͔͸Θ͔Βͳ͍ɻ͔͠͠ɼ

ʹࢀՃͨ࣌͠ʹ͸ɼ100 ਓ͍ۙग़੮ऀ͕͍ͨɻલճ

‫Ͱ·ࡏݱ‬ͷͱ͜Ζɼஶऀୡ͕ Nextef/γʔϧυ B ʹ͓͍

(10 ճ໨) ͸ɼ2017 ೥ 6 ݄ɼόϨϯγΞ (εϖΠϯ)ͯ୯ηϧ‫ۭܕ‬ಎΛ࢖ͬͯߦ͍ͬͯΔߴిքࢼ‫Ͱݧ‬͸ɼϒͰ։࠵͞Εͨ [26]ɻ

ϨʔΫμ΢ϯͷॠؒɼεϙοτ‫ܕ‬ͷൃޫ͕ଟ͘‫؍‬ଌ͞Ε͍ͯΔɻ·ͨɼS όϯυͷϑΥτΧιʔυిࢠॐʹϨʔβʔΛ౰ͯͯϒϨʔΫμ΢ϯΛ༠ൃͤ͞Δ࣮‫Ͱݧ‬΋ɼϒϨʔΫμ΢ϯͷॠؒʹً఺͕‫؍‬ଌ͞Εͨ [24]ɻ͜ΕΒͷ͜ͱ͔Βɼً఺͕ϒϨʔΫμ΢ϯɾτϦΨʔ‫ߏػ‬Λཧղ͢ΔͨΊͷ‫ͳʹݤ‬Δͱߟ͑ΒΕΔɻ‫ࡏݱ‬ɼஶऀୡ͸ɼՊ‫ݚ‬අΛ࢖ͬͨ‫఺ًͰڀݚ‬ͷਖ਼ମΛղ໌தͰ͋Δɻ• ʮInternational Workshop on Mechanisms of Vacuum Arcsʯ௨শ MeVArc ͱ‫ݺ‬͹ΕΔࠃࡍϫʔΫγϣοϓͰɼਅۭ์ి‫ݱ‬৅શൠͷ࣮‫ͱݧ‬ཧ࿦ΛΧόʔ͍ͯ͠Δɻ

CLIC ‫ܭ‬ը͕എ‫͋ʹܠ‬Δ͕ɼ෯޿͍෼໺͔Βͷࢀ
Ճ͕͋Δɻஶऀ͕ 2015 ೥ʹࢀՃͨ࣌͠ʹ͸ɼ50 ਓఔͷग़੮ऀ͕͓Γɼ੝‫ͨͬ͋Ͱگ‬ɻલճ (6 ճ໨) ͸ɼ2017 ೥ 3 ݄ɼΤϧαϨϜ (ΠεϥΤϧ) Ͱ։࠵͞Εͨ [20]ɻ

11
178

ँࣙ
‫ߘݪ‬ΛஸೡʹಡΜͰ͍͖ͨͩɼଟ͘ͷ͝ࢦఠΛͩͬͨ͘͞ KEK Ճ଎‫ث‬ͷං‫ޙ‬ᆹହࢯʹ‫ँײ‬ͷҙΛද͠·͢ɻ

CERN/CLIC άϧʔϓͷ‫ڞ‬ಉ‫ ऀڀݚ‬Walter Wuensch ࢯͱ Jan Paszkiewicz ࢯ͔Β͸ɼCLIC ϓϩτλΠ
ϓՃ଎؅ͷσʔλɼ͓Αͼਤͷ࢖༻‫ڐ‬ՄΛ͍͖ͨͩ·ͨ͠ɻ·ͨɼValery Dolgashev ࢯ (SLAC)ɼJiaru Shi ࢯ(ਗ਼՚େֶ)ɼFlyura Djurabekova ࢯ (ϔϧγϯΩେֶ)ɼ
Zhenxing Wang ࢯ (੢҆ަ௨େֶ) ͔Β΋ਤͷ࢖༻‫ڐ‬ՄΛ͍͖ͨͩ·ͨ͠ɻॏͶͯ‫ँײ‬ͷҙΛද͠·͢ɻ

509 MHz ࿈ଓ೾ۭಎͷ௚઀‫ݧ࣮࡯؍‬͸ɼSuperKEKBRF/ΞϨεۭಎάϧʔϓͰߦ͍·ͨ͠ɻຊ‫͝ʹڀݚ‬ཧղͱ͝‫ྗڠ‬Λ͍͖ͨͩɼ‫ँײ‬ͷҙΛද͠·͢ɻࢀߟจ‫ݙ‬[8] F. Wang, et al., “Performance Limiting Eﬀects
in X-Band Accelerators”, Phys. Rev. ST Accel.
Beams, 14 (2011) 010401. [Addendum, Phys. Rev.
ST Accel. Beams, 15 (2012) 120402].
[9] S. Matsumoto, T. Abe, Y. Higashi, T. Higo and
Y. Du, “High Gradient Test at Nextef and HighPower Long-Term Operation of Devices”, Nucl.
Instrum. Meth., A657 (2011) 160–167.
[10] X. Wu, T. Abe, H. Chen, T. Higo, S. Matsumoto,J. Shi and H. Zha, “High-Gradient Breakdown
Studies of X-Band Choke-Mode Structures”, inProceedings of the 8th International Particle Accelerator Conference (IPAC 2017) TUPAB010.
[11] X. Wu, “Design and Experiment of X-band HighGradient Choke-Mode Accelerating Structure”,
PhD thesis, ਗ਼՚େֶ (2017).

[1] ࡕҪ ‫ࢤ׮‬, “௒఻ಋՃ଎ۭಎ”, ߴΤωϧΪʔՃ଎‫ث‬ηϛφʔ OHO’15 ςΩετhttp://accwww2.kek.jp/oho/oho15/OHO15 txt/
07 Sakai Hiroshi 3.pdf (2015).

[12] দຊ मೋɼ໌ຊ ޫੜɼ޻౻ ঢɼઃָ ఩෉ɼதౡ ‫ܒ‬ޫɼං‫ ޙ‬ᆹହɼ෱ా ໜथɼদԼ ӳथɼԣࢁ ࿨ࢬɼ٢ా ޫ޺, “KEK X-Band RF ࢼ‫ࢪݧ‬ઃ (Nextef) ʹ͍ͭͯ”, ୈ 4 ճ೔ຊՃ଎‫ֶث‬ձ೥ձ (2007) TO03.

[2] M. Aicheler, et al., “A Multi-TeV Linear Collider Based on CLIC Technology”, CERN-2012-[13] Ѩ෦ ఩࿠, “ඍࡉߏ଄ʹΑΔಋମද໘ి࣓৔ͷมԽ007, SLAC-R-985,KEK-Report-2012-1, PSI-12-ʹؔ͢Δ‫”ڀݚ‬, ୈ 8 ճ೔ຊՃ଎‫ֶث‬ձ೥ձ (2011)01, JAI-2012-001(2012).

TUPS086.

[3] A. Winter, “Physics Potential of CLIC Operation
at 380 GeV”, CLICdp-Conf-2017-009(2017).

[14] Ѩ෦ ఩࿠ɼଞ, “ߴిք̭όϯυ୯ηϧࢼ‫ۭݧ‬ಎͷ̐෼ׂํࣜʹΑΔ੡࡞”, ୈ 9 ճ೔ຊՃ଎‫ֶث‬ձ೥ձ (2012) THPS095.

[4] D. A. Constable, “High Eﬃciency Klystron Development for Particle Accelerators”, in Proceedingsof eeFACT2016 (2016) WET3AH2.

[15] Ѩ෦ ఩࿠ɼଞ, “4 ෼ׂํࣜʹΑΔߴిքࢼ‫ ༻ݧ‬X
όϯυ୯ηϧۭಎͷ੡࡞”, ୈ 11 ճ೔ຊՃ଎‫ֶث‬ձ೥ձ (2014) SUP042.

[5] P. Wang, et al., “The RF Design of a Compact,
High Power Pulse Compressor with a Flat Output
Pulse”, in Proceedings of the 7th International
Particle Accelerator Conference (IPAC 2016) THPMW022.

[16] Ѩ෦ ఩࿠ɼଞ, “4 ෼ׂํ̭ࣜόϯυ୯ηϧ‫ۭܕ‬ಎͷߴిքࢼ‫ݧ‬ͷ݁Ռ”, ୈ 14 ճ೔ຊՃ଎‫ֶث‬ձ೥ձ

(2017) WEP039.
[17] A.

Cahill,V.

Dolgashev,

J.

Rosenzweig,[6] A. Grudiev, S. Calatroni and W. Wuensch, “NewLocal Field Quantity Describing the High Gradient Limit of Accelerating Structures”, Phys. Rev.
ST Accel. Beams, 12 (2009) 102001. [Erratum,
Phys. Rev. ST Accel. Beams, 14 (2011) 099902].

S. Tantawi and S. Weathersby, “Ultra High
Gradient Breakdown Rates in X-Band Cryogenic
Normal Conducting RF Accelerating Cavities”,
in Proceedings of the 8th International Particle
Accelerator Conference (IPAC 2017) THPIK125.

[7] V. Dolgashev, et al., “Geometric Dependence ofRadio-Frequency Breakdown in Normal Conducting Accelerating Structures”, Applied Physics
Letters, 97 (2010) 171501.

[18] A. Yeremian, V. Dolgashev and S. Tantawi,“RF Choke for Standing Wave Structures andFlanges”, Conf. Proc., C100523 (2010) THPEA065.

12
179

[19] F. Djurabekova, “Multiscale Simulation Model ofElectrical Breakdown: Current Status and Perspectives”, https://indico.cern.ch/event/521667/
contributions/2475391/ (2017).
[20] “The 6th International Workshop on Mechanismsof Vacuum Arcs (MeVArc2017)”,
https://indico.cern.ch/event/521667/ (2017).
[21] Ѩ ෦ ఩ ࿠, “SuperKEKB ཅ ి ࢠ μ ϯ ϐ ϯ άϦϯά༻ͷߴप೾Ճ଎ۭಎ࣮‫ ػ‬1 ߸‫׬͕ػ‬੒”, KEK Ճ଎‫ࢪڀݚث‬ઃτϐοΫε 2013/9/5,
http://www2.kek.jp/accl/topics/topics130905.html(2013).
[22] Ѩ෦ ఩࿠, “ߴप೾Ճ଎ۭಎͷϒϨʔΫμ΢ϯͷॠؒΛʮ‫ͨݟ‬ʯʂ”, KEK Ճ଎‫ࢪڀݚث‬ઃτϐοΫε
2016/10/5,
http://www2.kek.jp/accl/topics/topics161005.html(2016).
[23] T. Abe, T. Kageyama, H. Sakai, Y. Takeuchi andK. Yoshino, “Breakdown Study based on Direct In
Situ Observation of Inner Surfaces of an RF Accelerating Cavity during a High-Gradient Test”,
Phys. Rev. Accel. Beams, 19 (2016) 102001.
[24] J. Shao, et al., “Observation of Temporal Evolution Following Laser Triggered RF Breakdown in
Vacuum”, Phys. Rev. ST Accel. Beams, 17 (2014)
072002.
[25] “CLIC Workshop 2018”,
https://indico.cern.ch/event/656356/ (2018).
[26] “The 10th International Workshop on Breakdown Science and High Gradient Technology”,
https://indico.cern.ch/event/589548/ (2017).