501199‫ڦ‬఍㆟ሗ࿌

2017 International Workshop onFuture Linear Colliders (LCWS2017) ሗ࿌ (ຍ㏿ჾ)
KEK ຍ㏿ჾ◊✲᪋タ᳃ ᕝ ♸yu.morikawa@kek.jp
2018 ᖺ 1 ᭶ 29 ᪥1 ࡣࡌࡵ࡟2 ILC ᘓタࢥࢫࢺ๐ῶ࡟㛵ࡍࡿ㆟ㄽ 2017 ᖺ 10 ᭶ 23 ᪥࠿ࡽ 27 ᪥ࡢ 5 ᪥㛫ࠊࣇࣛࣥࢫࡢࢫࢺ

 ILC ຍ㏿ჾ⮬యࡢ◊✲㛤Ⓨ≧ἣ࠿ࡽ ILC ᘓタೃ⿵ᆅ࡛ࡢ

ࣛࢫࣈ࣮࡛ࣝ International Workshop on Future Linear Collidersලయⓗ࡞᪋タタィࡲ࡛ከᒱ࡟ࢃࡓࡿሗ࿌࣭㆟ㄽࡀ࡞ࡉࢀࡓࠋ(LCWS2017) ࡀ㛤ദࡉࢀࡓࠋLCWS ࡣᅜ㝿ࣜࢽ࢔ࢥࣛ࢖ࢲ࣮

ࡑࡢ୰࡛ࡶ㆟ㄽࡢ୰ᚰࡣ ILC ᘓタࢥࢫࢺ๐ῶ࡟ࡘ࠸࡚࡛࠶

(ILC) ࡸࢥࣥࣃࢡࢺࣜࢽ࢔ࢥࣛ࢖ࢲ࣮ (CLIC) ࡞࡝ࡢḟୡ௦ࡾࠊ௨ୗࡢࢫࢸ࣮ࢪࣥࢢᑟධࡸྛຍ㏿ჾࢥ࣏࣮ࣥࢿࣥࢺࡢᢏࣜࢽ࢔ࢥࣛ࢖ࢲ࣮ィ⏬ࢆ᥎㐍ࡍࡿୡ⏺ࡢ◊✲⪅ࡀ㞟࠺ᅜ㝿⾡㠉᪂࡟ࡼࡿᘓタࢥࢫࢺ๐ῶࡢྍ⬟ᛶࡀ㆟ㄽࡉࢀࡓࠋ఍㆟࡛࠶ࡿࠋ௒ᅇࡣ 19 ࠿ᅜ 265 ྡࡢཧຍࡀ࠶ࡾࠊෆ 62 ྡ

2.1 ILC ࡟࠾ࡅࡿࢫࢸ࣮ࢪࣥࢢࡀ᪥ᮏ࠿ࡽࡢཧຍ࡛࠶ࡗࡓࠋᅗ 1 ࡣ఍㆟ࡢ㞟ྜ෗┿࡛࠶ࡿࠋILC ࡢᙜึィ⏬ (TDR) ࡛ࡣࠊᐇ㦂㛤ጞ᫬ࡢ㔜ᚰ⣔࢚ࢿࣝ

ILC ࡟ࡘ࠸࡚ࡣࠊᩥ㒊⛉Ꮫ┬ࡀ᪥ᮏㄏ⮴ࢆ᳨ウࡋ࡚࠸ࡿ୰ࠊ

ࢠ࣮ࢆ 500 GeV ࡜ࡋ࡚タィࡋ࡚࠸ࡓࡀࠊࡇࡢᐇ㦂㛤ጞ᫬ࡢࡑࡢุ᩿࡟ྥࡅ࡚ᘓタࢥࢫࢺࡢ๐ῶࡀㄢ㢟࡜࡞ࡗ࡚࠸ࡿࠋᮏ㔜ᚰ⣔࢚ࢿࣝࢠ࣮ࢆࣄࢵࢢࢫ⢏Ꮚࡢヲ⣽

఍㆟࡛ࡶᚋ㏙ࡢࠕࢫࢸ࣮ࢪࣥࢢࠖࡸྛຍ㏿ჾࢥ࣏࣮ࣥࢿࣥࢺ

GeV ࡟ୗࡆ࡚タィࡋ࡞࠾ࡍࡇ࡜࡛ࢥࢫࢺ๐ῶࢆᅗࡾࠊᚲせࡢᢏ⾡㠉᪂࡟ࡼࡿࢥࢫࢺ๐ῶࡢྍ⬟ᛶ࡟ࡘ࠸࡚㆟ㄽࡉࢀࡓࠋ

࡟ᛂࡌ࡚ຍ㏿ჾࢆᘏ㛗ࡋ࡚࢚ࢿࣝࢠ࣮ࢆቑᙉࡍࡿࢫࢸ࣮ࢪ≉࡟ᢏ⾡㠉᪂࡟ࡼࡿࢥࢫࢺ๐ῶࡢྍ⬟ᛶ࡟ࡘ࠸࡚ࡣࠊ
ࠕILCࣥࢢࡀ㆟ㄽࡉࢀ࡚࠸ࡿࠋ
ࡇࡢࢫࢸ࣮ࢪࣥࢢ࡟ࡼࡾᚑ᮶ࡢ ILC

cost reduction by new technologyࠖ࡜࠸࠺≉ูࢭࢵࢩࣙࣥࢆタࡢ඲㛗ࡣ 31 km ࡛࠶ࡗࡓࡀࠊึẁࡢ඲㛗ࢆ 20 km ࡟ᢚ࠼ࡿࡅ࡚㆟ㄽࡉࢀࡓࠋ

ࡇ࡜ࡀ࡛ࡁࠊึẁࡢᘓタࢥࢫࢺࡶ᭱኱ 40%๐ῶ࡛ࡁࡿྍ⬟ ࡲࡓ ILC ᪥ᮏㄏ⮴࡟ྥࡅ࡚ࠊILC ᘓタࡢ᭷ຊೃ⿵ᆅ࡛࠶

ᛶࡀ࠶ࡿࠋᮏ఍㆟࡛ࡣ㔜ᚰ⣔࢚ࢿࣝࢠ࣮ࢆ 250 GeV ࡜ࡋࡓࡿᒾᡭ┴࡜ᮾ໭ ILC ᥎㐍༠㆟఍ྜྠࡢᮾ໭ᆅ༊ PR ࣈ࣮ࢫሙྜ࡟ࠊ඲యタィࡀ࡝࠺ኚࢃࡿ࠿࡞࡝ࡢࡼࡾヲ⣽࡞᳨ウࡢࡀタ⨨ࡉࢀࠊᮾ໭ᆅ᪉ࡢ㨩ຊࡸ ILC ᐇ⌧࡟ྥࡅࡓᆅඖࡢྲྀ

ሗ࿌ [1] ࡀ࠶ࡗࡓࠋᮏሗ࿌࡟ࡼࡿ࡜ࠊ250 GeV ∧ ILC ࡛ࡣᐃࡀྍ⬟࡞ 250ࡾ⤌ࡳࡀ⤂௓ࡉࢀࡓࠋࡑࡢ௚࡟ඛ➃ຍ㏿ჾ⛉Ꮫᢏ⾡᥎㐍༠

TDR ࡢタィ࡟ẚ࡭࡚ RF ࣘࢽࢵࢺࡸࢡࣛ࢖࢜ࣔࢪ࣮ࣗࣝࡢ㆟఍ (AAA) ࡸᮾ໭⤒῭㐃ྜ఍࠿ࡽẸ㛫௻ᴗࡢཧຍࡶ࠶ࡾࠊྎᩘࡀ 45%⛬ᗘ๐ῶࡉࢀࠊຍ㏿ჾࡢ㐠㌿㟁ຊࡶ 167 MW ࠿ᆅᇦ௻ᴗࡢ ILC 㛵㐃ᢏ⾡ࡢ⤂௓ࡶ࠶ࡗࡓࠋࡽ 129 MW ⛬ᗘࡲ࡛ᢚ࠼ࡽࢀࡿぢ㎸ࡳ࡜ࡢࡇ࡜࡛࠶ࡗࡓࠋᮏ఍㆟࡛⚾ࡣ ILC ࡢ⾪✺ᚋࡢࣅ࣮࣒ࢆṆࡵࡿ࣓࢖ࣥࣅ࣮

ࡇࢀࡽࢫࢸ࣮ࢪࣥࢢࡢ᳨ウ㈨ᩱࡣᅜ㝿ᑗ᮶ຍ㏿ჾጤဨ఍࣒ࢲࣥࣉ࡜ Undulator ගࢆṆࡵࡿࣇ࢛ࢺࣥࢲࣥࣉࡢ㛤Ⓨ≧ἣ(ICFA) ࡟ᥦฟࡉࢀ࡚࠾ࡾࠊ2017 ᖺ 11 ᭶ 6 ᪥࠿ࡽ 9 ᪥࡟㛤࡟ࡘ࠸࡚ሗ࿌ࡋࡓࠋ௨ୗ࡛ࡣ⚾ࡢ❧ሙ࠿ࡽぢ࠼ࡓ ILC ࡢຍദࡉࢀࡿ➨ 12 ᅇ ICFA ࢭ࣑ࢼ࣮࡛㆟ㄽࡉࢀࡿࡇ࡜࡟࡞ࡗ࡚

㏿ჾ࡟㛵ࡍࡿ఍㆟ෆᐜࢆሗ࿌ࡋࡓ࠸ࠋ

࠸ࡿࠋ࡞࠾ࠊ➨ 12 ᅇ ICFA ࢭ࣑ࢼ࣮ࡢ㆟ㄽࡢ⤖ᯝࠊ2017 ᖺ 11 ᭶8 ᪥࡟ ICFA ࡼࡾࠕ250 GeV ࡢ ILC ຍ㏿ჾᘓタࡢᨭᣢ࡜ ILC
᪩ᮇᐇ⌧ࢆዡບࠖࡍࡿኌ᫂ࡀⓎ⾲ࡉࢀ࡚࠸ࡿ [2] ࠋ2.2 ᢏ⾡㠉᪂࡟ࡼࡿࢥࢫࢺ๐ῶ
 ᅗ 2 ࡣຍ㏿ჾࡢࢭࢡࢩࣙࣥẖ࡟࠿࠿ࡿᘓタࢥࢫࢺࢆ♧ࡋ࡚࠸ࡿࠋILC ࡢᘓタࢥࢫࢺ඲యࡢෆࠊMain Linac 㒊ศࡢࢥࢫࢺࡀ⣙ 67%ࢆ༨ࡵ࡚࠾ࡾࠊMain Linac ࢆᵓᡂࡍࡿ㉸ఏᑟ RFࡢᢏ⾡㠉᪂࡟ࡼࡿࢥࢫࢺ๐ῶࡀ᭱ࡶຠᯝⓗ࡛࠶ࡿࠋ㉸ఏᑟRF ᢏ⾡࡟࠾ࡅࡿࢥࢫࢺ๐ῶࡢྍ⬟ᛶ࡜ࡋ࡚ࡣࠊࢽ࢜ࣈᮦຍᅗ 1㸸LCWS2017 ཧຍ⪅ࡢ㞟ྜ෗┿ᕤ㈝ཬࡧࢽ࢜ࣈᮦᩱ⮬యࡢప౯᱁໬ [3] ࡸࠊࢽ࢜ࣈ㉸ఏᑟ502200✵Ὕෆ㠃ࡢ❅⣲ῧຍ࡟ࡼࡿ㧗ຍ㏿㟁ሙཬࡧ㧗 Q ್ࡢᐇ⌧ILC ࡢ㝧㟁Ꮚ※࡜ࡋ࡚ࡣ 2 ࡘࡢ᪉ἲࡀ᳨ウࡉࢀ࡚࠸ࡿࠋ1[4] ࡞࡝ࡀሗ࿌ࡉࢀࡓࠋࢽ࢜ࣈ㉸ఏᑟ✵Ὕ࡬ࡢ❅⣲ῧຍᢏ⾡ࡘࡣ TDR ࡢ࣮࣋ࢫࣛ࢖ࣥ࡟࡞ࡗ࡚࠸ࡿ Undulator ගࢆ⏝࠸ࡣࣇ࢙࣑ࣝᅜ❧ຍ㏿ჾ◊✲ᡤ (FNAL) ࡛㛤Ⓨࡉࢀࡓࡶࡢ࡛ࠊࡓ㝧㟁Ꮚ⏕ᡂ᪉ἲ࡛࠶ࡿࠋUndulator ෆ࡛⺬⾜㐠ືࡋࡓ㟁ᏊTDR ࡛ࡢ㉸ఏᑟ✵Ὕࡢタィ್࡟ẚ࡭࡚ Q ್ࡣ 2 ಸ⛬ᗘ㧗ࣅ࣮࣒࠿ࡽⓎ⏕ࡍࡿ 7 MeV ⛬ᗘࡢගᏊࢆᶆⓗ࡟↷ᑕࡍࡿࡇࡃࠊຍ㏿㟁ሙࡶ᭱኱ 45 MV/m (༢ࢭࣝࢆ⏝࠸ࡓ⦪ ᐃࡢ⤖࡜࡛㝧㟁Ꮚࢆᚓࡿࠋࡇࡢ᫬ࠊⓎ⏕ࡋࡓගᏊࡣ෇೫ගࡋ࡚࠸ࡿᯝ) ࡢࡶࡢࡀᐇ⌧ࡉࢀ࡚࠸ࡿ (TDR ࡛ࡣࢡࣛ࢖࢜ࣔࢪ࣮ࣗࡓࡵࠊᚓࡽࢀࡿ㝧㟁Ꮚࡶ୍㒊ࡀ೫ᴟࡋ࡚࠸ࡿࠋ
ࡇࡢ Undulatorࣝࡢຍ㏿㟁ሙࢆ 31.5 MV/m ࡜ࡋ࡚࠸ࡿ) ࠋ⌧ᅾࠊᮏ❅⣲ῧ᪉ᘧࡢ㝧㟁ᏊⓎ⏕᪉ἲࡣ௚ࡢຍ㏿ჾ࡛ࡣᐇ⏝໬ࡉࢀࡓࡇ࡜ຍᢏ⾡࡟ࡘ࠸࡚ FNAL ࡜ KEK ࡛◊✲༠ຊࢆࡋ࡚࠾ࡾࠊ
KEKࡀ࡞࠸ࡓࡵࠊࡇࡢ Undulator ᪉ᘧࡢࣂࢵࢡ࢔ࢵࣉ࡜ࡋ࡚ࠊ௚ࡢᐇ㦂࡛ࡶ❅⣲ῧຍ࡟ࡼࡿ Q ್ୖ᪼ࡀ☜ㄆࡉࢀࡓ࡜ࡢࡇ࡜ࡢຍ㏿ჾ࡛ࡶᐇ⦼ࡢ࠶ࡿ㟁Ꮚ㥑ື᪉ᘧ࡟ࡼࡿ㝧㟁Ꮚ⏕ᡂࡶ࡛࠶ࡗࡓ [4] ࠋࡇࢀࡽࡢᢏ⾡ࡀᐇ⏝໬ࡉࢀࡓሙྜࠊࢽ࢜ࣈ㛤Ⓨࡉࢀ࡚࠸ࡿࠋࡇࡢ㟁Ꮚ㥑ື᪉ᘧࡢሙྜࡣࠊ3 GeV ࡢ㟁Ꮚᮦຍᕤ㈝ཬࡧࢽ࢜ࣈᮦᩱ⮬యࡢప౯᱁໬࡛ 2㹼3%ࠊ❅⣲ῧࣅ࣮࣒ࢆᶆⓗ࡟ᙜ࡚ࡿࡇ࡜࡛㝧㟁Ꮚࢆᚓࡿࡀࠊ㟁Ꮚ㥑ື᪉ຍ࡟ࡼࡿ Q ್ୖ᪼ࡢຠᯝ (ࢡࣛ࢖࢜ࢩࢫࢸ࣒ࡢ⡆⣲໬) ࡔᘧ࡛ࡣ೫ᴟࡋࡓ㝧㟁Ꮚࡣᚓࡽࢀ࡞࠸ࠋࡅ࡛ 5%⛬ᗘࡢᘓタࢥࢫࢺ๐ῶࡀぢ㎸ࡲࢀ࡚࠸ࡿࠋ❅⣲ῧຍᶆⓗࡢ㛤Ⓨ࡟ࡘ࠸࡚ࡣࠊUndulator ᪉ᘧ࡜㟁Ꮚ㥑ື᪉ᘧ࡛࡟ࡼࡾຍ㏿㟁⏺ࢆቑᙉ࡛ࡁࢀࡤࡉࡽ࡞ࡿࢥࢫࢺ๐ῶࡀぢ㎸⇕㈇Ⲵ࡞࡝ࡀ␗࡞ࡿࡓࡵࠊ
ࡑࢀࡒࢀูࡢタィ࡛㛤Ⓨࡀ㐍ࡵࡽࡵࡿ࡜ࡢࡇ࡜࡛࠶ࡗࡓࠋ

ࢀ࡚࠸ࡿࠋUndulator ᪉ᘧࡢᶆⓗ㛤Ⓨࡣ୺࡟ࢻ࢖ࢶ㟁Ꮚࢩࣥୖグࡢ㉸ఏᑟ✵Ὕᢏ⾡௨እ࡟ࡶࠕILC cost reduction by newࢡࣟࢺࣟࣥ (DESY) ◊✲ᡤࡀ୺ᑟࡋ࡚࠸ࡿࠋᶆⓗࡢᮦ㉁࡟

technologyࠖ࡜࠸࠺≉ูࢭࢵࢩࣙࣥ࡟࡚ᢏ⾡㠉᪂࡟ࡼࡿࢥࢫࡣࢳࢱࣥྜ㔠ࡀ⏝࠸ࡽࢀࠊ⇕㈇Ⲵࢆศᩓࡉࡏࡿࡓࡵ࡟ᶆⓗࢆࢺ๐ῶࡢྍ⬟ᛶࡀ㆟ㄽࡉࢀࡓࠋࡇࡢࢭࢵࢩ࡛ࣙࣥࡣࠊࢲࣥࣆᅇ㌿ࡉࡏ࡞ࡀࡽࣅ࣮࣒ࢆཷࡅࡿࠋ⇕㈇Ⲵࡣ 4 kW ⛬ᗘ࡛࠶ࡿࣥࢢࣜࣥࢢࡸ㟁Ꮚ࣭㝧㟁Ꮚ※࡞࡝ࡢຍ㏿ჾࡢࢭࢡࢩࣙࣥẖ࡟ࡓࡵ⇕㍽ᑕ࡟ࡼࡿ෭༷᪉ᘧࡀ᥇⏝ࡉࢀ࡚࠸ࡿࠋ⌧ᅾࡣ⇕ᛂ᪂ᢏ⾡࡟ࡼࡿࢥࢫࢺ๐ῶࡢྍ⬟ᛶࡀ࡞࠸࠿㆟ㄽࡀ࡞ࡉࢀࡓࠋ

ຊ⦆࿴࡟ࡴࡅ࡚ࢹࢨ࢖ࣥࡢ᭱㐺໬ࡸᶍᆺヨ㦂࡞࡝ࡀィ⏬ࡉỌஂ☢▼ࢆ࣮࣋ࢫ࡟ࡋࡓࢲ࢖࣏࣮ࣝ㟁☢▼ [5] ࡸࠊ❅໬ࢳࢀ࡚࠸ࡿ [8] ࠋࢱࣥ (TiN) ࢥ࣮ࢸ࢕ࣥࢢ௜⤯⦕ࢭ࣑ࣛࢵࢡࢆࢥ࣮ࢸ࢕ࣥࢢ㟁Ꮚ㥑ື᪉ᘧࡢᶆⓗ㛤Ⓨࡣ୺࡟ KEK࡜ᗈᓥ኱Ꮫࡀඹྠࡋ୙せࡢ᪂⣲ᮦࢭ࣑ࣛࢵࢡ࡟⨨ࡁ᥮࠼ࡓ RF ධຊࣃ࣮࣡࢝ࣉ࡚㐍ࡵ࡚࠸ࡿࠋᶆⓗࡢᮦ㉁࡟ࡣࢱࣥࢢࢫࢸࣥྜ㔠ࡀ⏝࠸ࡽ࣮ࣛ [6] ࡞࡝ࡀ㆟ㄽࡉࢀࡓࠋ

ࢀࠊUndulator ᪉ᘧ࡜ྠࡌࡃᶆⓗࢆᅇ㌿ࡉࡏ࡞ࡀࡽࣅ࣮࣒ࢆཷࡅࡿࠋ⇕㈇Ⲵࡣ᭱኱ 30 kW ࡟ࡶ࡞ࡿࡓࡵỈ෭᪉ᘧ࡜࡞ࡗ࡚࠸ࡿࠋᅇ㌿㍈ࡢࢩ࣮ࣝᮦ࡟ࡣ☢ᛶὶయࡀ⏝࠸ࡽࢀ࡚࠾ࡾࠊ⌧ᅾࡣ☢ᛶὶయࢆ⏝࠸ࡓᶍᆺ࡟ࡼࡿ┿✵ヨ㦂ࡀ⾜ࢃࢀ࡚࠸ࡿ [9] ࠋ3.2 ILC ࣅ࣮࣒ࢲࣥࣉࡢ㛤Ⓨ
 ILC ࡟ࡣ඲ 15 ᇶࡢࣅ࣮࣒ࢲࣥࣉࡀ࠶ࡾࠊ⚾ࡣࡇࡢ୰࡛ࡶ
᭱኱ࣅ࣮࣒ࣃ࣮࣡ 14 MW ࡢ㟁Ꮚࡲࡓࡣ㝧㟁Ꮚࣅ࣮࣒ࢆ
Ṇࡵࡿ࣓࢖ࣥࣅ࣮࣒ࢲࣥࣉ࡜᭱኱ 300 kW ࡶࡢ Undulator ගࢆṆࡵࡿࣇ࢛ࢺࣥࢲࣥࣉࡢ㛤Ⓨࢆ㐍ࡵ࡚࠸ࡿࠋ ࣓࢖ࣥࣅ࣮࣒ࢲࣥࣉࡢࢹࢨ࢖ࣥࡣ SLAC ᅜ❧ຍ㏿ჾ◊✲ᡤ࡟࡚ࣅ࣮࣒ࣃ࣮࣡2.2 MW ⏝࡟㛤ⓎࡉࢀࡓỈࢲࣥࣉ [10]ᅗ 2㸸ຍ㏿ჾࡢࢭࢡࢩࣙࣥẖ࡟࠿࠿ࡿᘓタࢥࢫࢺ [7]ࢆ࢔ࢵࣉࢢ࣮ࣞࢻࡋࡓࡶࡢ࡛࠶ࡿࠋᅗ 3 ࡟ ILC ࣓࢖ࣥࣅ࣮

㸨ILCU (ILC unit)㸸ILC ࢥࢫࢺホ౯࡟⏝࠸ࡽࢀࡿᇶ‽࣒ࢲࣥࣉࡢᵓ㐀ࢆ♧ࡍࠋືసཎ⌮࡜ࡋ࡚ࡣࠊỈ࡛ࣅ࣮࣒⇕ࢆ

㏻㈌࡛࠶ࡾࠊ2012 ᖺ 1 ᭶᫬Ⅼࡢ⡿ࢻࣝ࡟┦ᙜࡍࡿࠋ྾཰ࡋࠊࡑࡢỈࢆᙉไᑐὶࡉࡏࡿࡇ࡜࡛ࣅ࣮࣒⇕ࢆ㍺㏦ࡋ

3 ILC ຍ㏿ჾࡢᢏ⾡㛤Ⓨ෭༷ࡍࡿ࡜࠸࠺ࡸࡾ᪉࡛࠶ࡿࠋILC ࣓࢖ࣥࣅ࣮࣒ࢲࣥࣉࡢᇶᮏࢹࢨ࢖ࣥ[11] ࡣࡍ࡛࡟᏶ᡂࡋ࡚࠸ࡿࡶࡢࡢࠊ࠸ࡃࡘ࠿ࡢ ⚾ࡣ ILC ࣅ࣮࣒ࢲࣥࣉࡢ㛤Ⓨ≧ἣࡢሗ࿌ࡢࡓࡵ࡟ᮏ఍㆟ᢏ⾡ㄢ㢟ࡀṧࡗ࡚࠸ࡿࠋࡑࡢෆࡢ୍ࡘࡀࣅ࣮࣒❆ࡢ⪏ஂᛶ࡟ཧຍࡋࡓࠋࣅ࣮࣒ࢲࣥࣉ࡜ྠᵝ࡟ࣁ࢖ࣃ࣮࣡ࣅ࣮࣒ࢆཷࡅ࡛࠶ࡾࠊ௒ᅇࡢ఍㆟࡛ࡣࡇࡢࣅ࣮࣒❆ࡢ⪏ஂᛶホ౯ࢆሗ࿌ࡿ㝧㟁Ꮚ※ᶆⓗ࡟ࡶ㛵ᚰࡀ࠶ࡾࠊ
ࡇࢀࡽࡢࢭࢵࢩࣙࣥ࡟ࡶཧࡋࡓ[12] ࠋᅗ 4 ࡣࣅ࣮࣒❆࡟࠿࠿ࡿᛂຊ࡜ࣅ࣮࣒❆ ᗘࡢຍࡋࡓࠋ௨ୗ࡛ࡣ㝧㟁Ꮚ※ᶆⓗ࡜ࣅ࣮࣒ࢲࣥࣉ㛤Ⓨ≧ἣ࡟❆ཌ౫Ꮡᛶ࡛࠶ࡿࠋࣅ࣮࣒❆ࢆཌࡃࡍࡿ࡜❆ࡘ࠸࡚ሗ࿌ࡍࡿࠋࡶࡢࡢࠊ❆ࢆཌࡃࡍࡿࡇ࡜࡛Ỉࡢᅽຊ࡟ࡼࡿᛂຊࡣ⦆࿴ࡉࢀ3.1 ILC 㝧㟁Ꮚ※ᶆⓗࡢ㛤Ⓨ5 mm ཌࡲ࡛ࡣࣅ࣮࣒❆୰ࡢ᭱኱┦ᙜᛂຊࡣῶᑡࡋ࡚࠸ࡃࠋ

ᗘࡀୖࡀࡿ

5 mm ௨ୖཌࡃࡍࡿ࡜ࣅ࣮࣒࡟ࡼࡿ⇕⭾ᙇࡀ኱ࡁࡃ
ࡋ࠿ࡋࠊ503201
࡞ࡾࠊ᭱኱┦ᙜᛂຊࡶቑ኱ࡍࡿࡇ࡜ࡀศ࠿ࡗࡓࠋ⌧ᅾࡢࣅ࣮࣒❆ཌࡣ 1 mm ࡜ࡋ࡚࠸ࡿࡢ࡟ᑐࡋࠊࡇࡢゎᯒ⤖ᯝ࠿ࡽࣅ࣮

4 ࠾ࢃࡾ࡟

࣒❆ཌࡣᑡ࡞ࡃ࡜ࡶ 5 mm ⛬ᗘࡲ࡛ࡣཌࡃ࡛ࡁࡿ࡜ゝ࠼ࡿࠋ ௒ᅇࡢ LCWS ࡛ࡣ ILC ᐇ⌧࡟ྥࡅ࡚せ⣲ᢏ⾡ࡢ◊✲㛤Ⓨ ࣇ࢛ࢺࣥࢲࣥࣉ࡟ࡘ࠸࡚ࡣࠊTDR タィ࡛ࡣ࣓࢖ࣥࣅ࣮࣒

ࡔࡅ࡛࡞ࡃࢥࢫࢺ๐ῶࡢ㆟ㄽࡶࡼࡾලయⓗ࡞ࡶࡢ࡟࡞ࡗ࡚ࢲࣥࣉ࡜ྠᵝ࡟Ỉࢲࣥࣉࢆᇶ࡟ࡋࡓࢹࢨ࢖࡛ࣥ࠶ࡗࡓࡀࠊỈࡁࡓࠋཧຍ⪅࡜ヰࡋ࡚࠸࡚ࡶ ILC ᐇ⌧࡬ࡢពẼ㎸ࡳࡀឤࡌࡢᨺᑕ໬࡟ࡼࡿࢺࣜࢳ࣒࢘ࡢ኱㔞Ⓨ⏕࡜࠸ࡗࡓㄢ㢟ࡀ࠶ࡗࡽࢀࠊ
ILC ᐇ⌧ࡀࡍࡄࡑࡇࡲ࡛㏕ࡗ࡚࠸ࡿࡼ࠺࡟ᛮࢃࢀࡓࠋࡓࠋ
ᮏ఍㆟࡛ࡣࣇ࢛ࢺࣥࢲࣥࣉࢆࢢࣛࣇ࢓࢖ࢺ〇࡛ฟ᮶࡞࠸ ⚾ࡣ KEK ࡢ 2 ᖺ┠ᢏ⾡⫋ဨ࡛࠶ࡿࡀࠊᑗ᮶ ILC ࡢ⯙ྎ࡛࠿࡜࠸࠺᳨ウෆᐜࢆሗ࿌ࡋࡓ [13] ࠋࢢࣛࣇ࢓࢖ࢺ࡜㔠ᒓࡢά㌍࡛ࡁࡿࡼ࠺࡟௒࠿ࡽᢏ⾡ࢆ☻࠸࡚࠸ࡁࡓ࠸ࠋ᥋ྜ᪉ἲ࡞࡝ᢏ⾡ㄢ㢟ࡀᣦ᦬ࡉࢀࡓࡀࠊࢢࣛࣇ࢓࢖ࢺ〇ࣇ࢛ࢺࣥࢲࣥࣉࡣ௒ᚋࡶ᳨ウࢆ㐍ࡵࡿ౯್ࡣ࠶ࡿ࡜ࡢࢥ࣓ࣥࢺࡶ࠶ࡗࡓࠋ௒ᅇࡢ㆟ㄽࢆ㋃ࡲ࠼࡚ࡼࡾヲ⣽タィࢆ㐍ࡵࡓ࠸ࠋᅗ 3㸸ILC ࣓࢖ࣥࣅ࣮࣒ࢲࣥࣉࡢᵓ㐀ᅗ 4㸸❆ ᗘ࡜❆࡟࠿࠿ࡿᛂຊࡢ❆ཌ౫Ꮡᛶཧ⪃ᩥ⊩[1] S. Michizono,”ILC accelerator status and optimization”,
LCWS2017 Plenary session.
[2] “ICFA Statement on the ILC Operating at 250 GeV as a Higgs
Boson Factory”, The 12th ICFA Meeting, November 2017[3] T. Dohmae, “Activities of Cavity fabrication Facility”,
LCWS2017 Super conducting RF session.
[4] K. Umemori, “N-doping/infusion study in KEK/J-PARC”,
LCWS2017Super conducting RF session.
[5] N. Terunuma, “Damping Ring”, LCWS2017 ILC cost reduction by new technology session.
[6] Y. Yamamoto, “Cost reduction for power coupler”,
LCWS2017 ILC cost reduction by new technology session.
[7] ILC Technical Design Report volume䊢 part䊡[8] S. Riemann, “The ILC positron source target using cooling bythermal radiation”, LCWS2017 Sources session.
[9] T. Omori, “Rotation Target R and D of ILC E-driven source”,
LCWS2017 Sources session.
[10] R.B. Neal, “SLAC 2.2MW Water Dump”, The Stanford TwoMile Accelerator.
[11] P. Satyamurthy et al, “Design of an 18MW vortex flow water
beam dump for 500GeV electrons/positrons of an international linear collider”, Nuclear Instruments and Methods inPhysics Research A 679 (2012).
[12] Y. Morikawa, “Simulation Study of ILC Main Beam Dump
Window”, LCWS2017 Beam Delivery session.
[13] Y. Morikawa., “A Photon Dump Study for ILC Undulator
Positron Source”, LCWS2017 Sources session.