501 ⤂✲◊ڦ Belle II ࢥࡢࢸ ࢢ ࡢࡑඛ࠶ ࡢKEK ⣲⢏ᏊཎᏊ᰾◊✲ᡤ ཎ 㝯ᐉ [email protected] 2015 ᖺ㸦ᖹᡂ 27 ᖺ㸧5 ᭶ 9 ᪥ 1 ࡌࡣ ⌧ᅾࡢ⣲⢏Ꮚᐇ㦂࠸࠾ࡣ㸪ຍ㏿ჾࡢ㧗ࢠ 㧗㍤ᗘ㸪ほ ⨨ࡢᆺ㸪⢭ᐦ ᐃࡢᚲせ ᛶฟჾࡢ⣽ᐦ㸪ฟຊಙሗࡢヲ⣽ࡀ㐍 ࠸ࡇࠋฟຊࢹࢱ㔞ࡢቑຍࡣ㸪ࡇࡢᐇ㦂㸪 ≉ィ⟬ᶵ࠶ࡢ᪉ኚࠋࡓ࠼CERN ࡢATLAS[1] ࠾ ࡧCMS[2] ᐇ㦂 Higgs ⢏ᏊࡢⓎぢࡢ㢌Ⓨ⾲ㄽ [3,4]࠸࠾㸪ฟჾ㸪ຍ㏿ჾ୪ィ⟬ᶵࡢ㔜せᛶ ࡀゝཬࡉ࠸ࡇࠋࡣୡ⏺つᶍࡢศᩓィ⟬ࢹࡢᐇ⌧ ࡢࡑᡂຌពࡋ࠸ࠋLHC ᐇ㦂ࡣ㸪ୡ⏺ᆅ ࠶ィ⟬ᶵ㈨※ࢺࢡ᭷ᶵⓗࡂ࡞ࡘ㸪ࡑィ ⟬ᶵࡢᵝࡢ㐪࠸྾ࡋ㸪ࡘᚲせ࡞ሗ⤫ⓗ ࠼࠺ࡍࢻᑟධࡍࡇ㸪ୡ⏺ つᶍࡢศᩓィ⟬ࢹ⌧ᐇࡋࡑࠋࡓࡋ㸪᪥ᮏ⾜ ḟୡ௦ B ࢺࢡᐇ㦂࠶ Belle II 㸪࠸ ࠸ศᩓィ⟬ࢹᑟධࡋ㸪 ࡋࡑ㐠⏝ࡍࡇ┠ᣦࡋ㸪 ᅜෆእ✲◊ࡢ⪅ࡀ᪥✲◊ࠎάᒎ㛤ࡋ࠸ࡇࡑࠋ㸪 ࡢࡇሙ㸪 Belle II ᐇ㦂ࡅ࠾ศᩓィ⟬ࢹ ⌧ࡢ≧⤂ࡍ ࠋ2 Belle II ศᩓィ⟬ࢹ 2.1 せ ồ 2016 ᖺࢥࢩࢽࢢ㛤ጞࡍ SuperKEKB ຍ㏿ჾࡣ㸪KEKB ຍ㏿ჾ ࡢ40 ಸ┦ᙜࡍ▐㛫 ࢩࢸ 35 2 1 8 10 cm s u ┠ᶆࡋ࠸ࡋࡑࠋຍ㏿ჾࡢᛶ⬟ ┠ࡀᶆ㐩ࡓࡋ㝿 ࡣ1.8 GB/s ࢹ⏕ࡢࡀࢱฟჾ ᖖ㌿㏦㸪グ㘓ࡉ㸪⤊ⓗ✚⟬ࢸࢩࡋ 50 1 ab 㸪ᐜ㔞ࡍ⣙ 100PB 㐩ࡍࢹ⏕ࡀࢱᡂࡉ ᮇᚅࡉࡉࠋࢹ⏕ࡢࡇࢱฎ⌮ࡋ㸪≀⌮ゎᯒ ⏝ࡁᙧᘧኚ㸪ಖᏑࡋ㸪ࡓᐇࢹࢱᑐᛂ ࡓࡋࢩࢩࡢసᡂ⾜࠺ᚲせ࠶ࡇࠋࢹࡢ ࢱࡏ ࡃࡌ100PB つᶍ࠶ࠋ᪉㸪ࡇࡢฎ ⌮㸪సᡂ࡞せࡍ CPU 㔞⣙ 10 ࢥ࡞ࡇࠋ ࡣCERN ⾜࠸ᆺࢻ⾪✺ᆺຍ㏿ჾ (LHC)[5] ࡅ࠾ ATLAS CMS ᐇ㦂 ࡀRun1 ᐇ㝿 ⏝ࡓࡋ㈨※㔞༉ࡍࡢ࠶ ࠋࡉ㸪 ࡇࡢィ⟬ᶵ㈨※◊✲ᶵ㛵㈥࠼ࡢ ࠋ๓㌟ࡓ࠶ Belle ᐇ㦂 ࡣ1999 ᖺ 2010 ᖺࡢ㐠㌿ᮇ㛫୰ ⣙1 1 ab ࢹࡢࢱグ㘓ࡋࡑࠋࡓࡋ㸪 ࢹࡢࡇࡢࢱฎ⌮㸪 ࢩࢩࡢసᡂ㸪ࢨゎᯒ⮳ ᡤ✲◊ࡢタ࠶ KEK ⾜࠺㸪ᴟ㞟୰ᆺィ⟬ ࢹ᥇⏝ࡇࠋࡓࡋࡣ㸪Belle ᐇ㦂ࡇࡀⓎಙࡓࡋ ከࡢࡃ≀⌮ゎᯒ⤖ᯝドࡁ࠺㸪ࢹࡢࡇࢱ㔞 ᑐࡋ㠀ᖖ࠺ࡃᶵ⬟ࡋࠋࡓࡋࡋ㸪Belle II ᐇ㦂ࡣ ࠺࠶࠺ࠋBelle ᐇ㦂 ࡢ50 ಸ┦ᙜࡍࢹࢱ ࡃ࡞ฎ⌮ࡍࡇࡀ㸪ᯝࡋࡓ◊✲ᶵ㛵ࡁࡢ ࠋ࠺ࡘ⪃៖ࡍࡣࡁ㸪ඹ◊✲⪅ࡀᆅ⌮ⓗୡ⏺୰ ศᕸࡋ࠸ࡇ࠶ࠋBelle II ᐇ㦂ࡣ᪥ᮏࡣ ࣓㸪ࢻࢶ㸪㡑ᅜ㸪ࢱ㸪‴㸪 ࢺࢫ㸪࡞ࢲࢼࢪ㸪㸪⡿ 23 ᅜ ᆅᇦ㸪99 ◊✲ᶵ㛵Ꮫᡤᒓࡍ⣙ 600 ே✲◊ࡢ⪅ࡀཧ ຍࡋ࠸ࠋᆺᅜ㝿ඹᐇ㦂ࡣᅜ◊✲ᶵ㛵ࡀᢸᙜ ࡍฟჾỴ㸪ࡑࡒࡀ༠ຊࡋฟჾయᘓタ ࡋࡇࡃ࠸ࡀᖖ㆑࠶ࡋࡑࠋ LHC ᐇ㦂ࡢᡂຌ௨㝆㸪 ฟჾᵝ㸪ィ⟬ᶵ࠸࠾ᅜ◊✲ᶵ㛵ࡢศᢸ ☜ࡋ㸪༠ຊࡋィ⟬ᶵࡢ㐠Ⴀ⾜ࡇ࠺ࡀᐇ㦂ᡂຌ ᑟࡃ㘽ࡗ࡞࠸ࡇࡇࠋ㸪Belle II ཧ⏬ࡋ࠸ᶵ 㛵┠ࡅ㸪ࡇࡑ✀ࡣ㢮࡞␗ࡢከࡢࡃィ⟬ᶵ㈨ ࡀ※Ꮡᅾࡋ࠸ࡇࠋ࠺ࡃ⏝ࡍࡇࡀ ࡞ࡁ࠸ࡢ ࠋࡇࡢࡘၥ࠸ࡅᑐࡍ⟅ࡍࡣ࠼࠶ࠋLHC ᐇ㦂ᡂຌࢢࡓࡋ ࢻ ࢥࢸ ࢢ㸦௨ୗࢢ ࢻࡍ㸧࠶ࡇࠋ ࡣLHC ᐇ㦂ࢹࡢࢱゎᯒᚲせ ࡞ィ⟬ᶵ㈨※ഛࡍࡓస ࡓWLCG (Worldwide LHC Computing Grid)[6] ࡀయ࡞㸪ᚲせ࡞ࢻ ࡢ㛤Ⓨᐇ⾜ࡇ࠺ᐇ⌧ࡉࡋࡑࠋࡓ㛤Ⓨࡉ ࡓᵝ࡞ࠎᇶ┙ ࢶ ࡣLHC ᐇ㦂௨እ⏝ࡍࡇ ࡀチࡉ࠸ࠋࡓ㸪Belle II ᐇ㦂ཧຍᶵ㛵ࡢከࡣࡃ㸪᪤ 13