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Future B Physics Program at KEK

Future B Physics Program at KEK. (KEKB upgrade strategy). - KEK’s Roadmap -. BNM 2008 (24-Jan, Atami) Y.Sakai, KEK based on slides by Masa Yamauchi, KEK. Outline. Introduction: KEKB and Belle Next program of quark flavour physics KEK’s five year roadmap

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Future B Physics Program at KEK

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  1. Future B Physics Program at KEK (KEKB upgrade strategy) - KEK’s Roadmap - BNM 2008 (24-Jan, Atami) Y.Sakai, KEK based on slides by Masa Yamauchi, KEK

  2. Outline • Introduction: KEKB and Belle • Next program of quark flavour physics • KEK’s five year roadmap • KEKB upgrade plan → Onishi’s talk • Detector issues • Organization of new experimental group • Summary

  3. KEKB and Belle

  4. Belle Detector Cherenkov detector n=1.015~1.030 SC solenoid 1.5T 3.5GeV e+ EM calorimeter (CsI(Tl)) TOF counter 8GeV e- Central drift chamber He(50%)+C2H6(50%) m / KL detector Si vertex detector

  5. 14 countries, 55 institutes, ~400 collaborators The Belle Collaboration Seoul National U. Shinshu U. Sungkyunkwan U. U. of Sydney Tata Institute Toho U. Tohoku U. Tohuku Gakuin U. U. of Tokyo Tokyo Inst. of Tech. Tokyo Metropolitan U. Tokyo U. of Agri. and Tech. INFN Torino Toyama Nat’l College VPI Yonsei U. Nagoya U. Nara Women’s U. National Central U. National Taiwan U. National United U. Nihon Dental College Niigata U. Nova Gorica Osaka U. Osaka City U. Panjab U. Peking U. Princeton U. Riken Saga U. USTC BINP Chiba U. U. of Cincinnati Ewha Womans U. Fu-Jen Catholic U. U. of Giessen Gyeongsang Nat’l U. Hanyang U. U. of Hawaii Hiroshima Tech. IHEP, Beijing IHEP, Moscow IHEP, Vienna ITEP Kanagawa U. KEK Korea U. Krakow Inst. of Nucl. Phys. Kyoto U. Kyungpook Nat’l U. EPF Lausanne Jozef Stefan Inst. / U. of Ljubljana / U. of Maribor U. of Melbourne

  6. B0J/yKS G(BfCP;t) - G(BfCP;t) G(BfCP;t) + G(BfCP;t) Scientific Achievements of B Factories (1) Observation of CPV in the B meson system ACP(t) = = Af cosDmt + Sf sinDmt Belle, July 05 B0J/yKS Belle, July 05 Af ~ 0 Sf = 0.652±0.039±0.020 Consistent with BaBar’s meas.

  7. B0J/yKS Achievements of the B Factories Quantitative confirmation of the KM model Belle, July 05 B0J/yKS Discovery of CP violation in BB system Af ~ 0 Sf = 0.652±0.039±0.020 Belle, July 05 Violation of CP symmetry !

  8. Other highlights Many new resonances Evidence forBgtn AFB in BgK*l+l- X(3872) Z(4430) Belle, 2005 SM D0-D0 mixing Bgdg transition BgD*tn and more…

  9. Another important achievement • Success of KEKB and PEP-II enabled us to design a new e+e-B factory with much higher Lpeak. Asymmetric e+e- collider with L > 1034

  10. What is next with flavour physics? • If new physics at O(1)TeV… • It is natural to assume that the effects are seen in B/D/t decays. • Flavour structure of new physics? • CP violation in new physics? • These studies will be useful to identify mechanism of SUSY breaking, if NP=SUSY. • Otherwise… • Search for deviations from SM in flavor physics will be one of the best ways to find new physics.

  11. KEKB upgrade • Asymmetric energy e+e- collider at ECM=m((4S)) to berealized by upgrading the existing KEKB collider. • Super-high luminosity  21035/cm2/sec 210 9 BB per yr.  210 9t+t- per yr. (1st stage: >x10) Belle with improved rate immunity Higher beam current, more RF, smaller by* and crab crossing  L = 21035/cm2/sec • final target ~81035/cm2/sec (smooth transition: 50 ab-1) http://belle.kek.jp/superb/loi

  12. Physics at upgraded KEKB New source of CP violation New source of flavor mixing Precision test of KM scheme LFV t decays SUSY breaking mechanism Charm physics New resonances, D0D0 mixing… Super-high statistics measurements: aS, sin2qW, etc.

  13. SUSY flavour physics: mass matrix of squark and slepton will be determined by their direct production at the energy frontier and flavour physics measurements. Quark flavor changing processes Off-diagonal Diagonal LHC/ILC SUSY mass spectrum Lepton flavor violation Y.Okada, Nov. 2007

  14. Searches for new sources of quark mixing and CP violation CP asymmetries of penguin dominated B decays Deviation from SM Present upper limits New source of CP violation Deviation from SM Measurements at upgraded KEKB Relevant to baryogenesis? （ ab-1） Reach of present B factories Reach of upgraded KEKB

  15. A possible hint for NP: b→sqq Theory : tends to positive shifts Smaller than bgccs in 7 of 9 modes

  16. Precise measurements of t decays LFV violating t decay? Upper limits Branching Fraction t->mg m->eg New Physics predictions t->eg Integ. Lum.（ ab-1） T.Goto et al., 2007 Reach of B factories Upgraded KEKB

  17. n B H+/W+ t+ B decays with more than one n Interactions of H± B e- e+ Υ Bgtn decays B p Belle, 2006 D 400fb-1 full reconstruction 0.2~0.3% for B+ 10ab-1 Provides a unique method to measure b-H±-u and b-H±-ccoupling strength. Search region with Bgtn decays

  18. B decays into invisible particles? Light dark matter? _ B  K(*)nn [or cc] Heavy darm matter is being searched for in direct detection experiments. Model prediction Light dark matter can be Searched for in the upgraded KEKB.

  19. Search for right handed interaction Left-right summetry in new physics? CP violationin B  KSp 0g Sizable CP asymmetry is expected in B0Xg decay, if right-handed interaction exists in new physics. Present exp. precision Precision of the measurement U-KEKB Reach of upgradedKEKB SM T.Goto et al., 2007

  20. New resonances New resonances found at Belle/BaBar More than 10 new resonances have been found at B factories Y(4660) Y(4008) Z(4430) DsJ(2860) DsJ(2700) Xcx(3090) Among them X（3872） and Z（4430） are considered to be “exotic” states. Y(4320) cc2’ X(3940), Y(3940) Y(4260) Sc* baryon triplet X(3872) More and more exotic states will be Observed by the upgraded KEKB. D0*0& D1*0 DsJ(2317/2460) hc’ & e+e-cccc

  21. Identification of SUSY breaking scenario Pattern of deviations from the Standard Model Y.Okada Observ- ables SUSY models ++: Large, +: sizable, -: small

  22. Strong competitors

  23. Comparison with LHCb LHCb is advantageous in… e+e-is advantageous in… CPV inB→fKS, h’KS,… CPV inB→J/yKS CPV inB→KSp0g Most of B decays not including n or g B→Knn, tn, D(*)tn Time dependent measurements of BS Inclusive b→smm, see t→mg and other LFV B(s,d)→mm D0D0mixing Bcand bottomed baryons These are complementary to each other !!

  24. Roadmap -HEP- Energy Frontier ILC R&D Construction Experiment LHC • According to the JAHEP community’s master plan, • Highest priority is given to ILC • Before ILC, promote flavor physics at KEKB and J-PARC • Action before the ILC approval • ILC R&D • Completion/commissioning of J-PARC • Considering the world competition, it is urgent to improve neutrino intensity • Continuation of KEKB/Belle with upgrade Flavor Physics at Luminosity/Intensity Frontier , K, ,... at J-PARC b, c, ,... with upgraded- KEKB/Belle

  25. KEK Web page (5 Year Plan)

  26. KEK Roadmap : KEKB First 3 years: shutdown • Replace beam pipe (with ante-chamber) • Upgrade interaction region • Upgrade ground level RF facility • Improve crab cavities fundamental part Last 2 years: operation & improvements • Installation of Damping Ring • Installation of additional RF • Reinforcement of cooling facility  Onishi’s talk 1st goal: 2 x 1035cm-2sec-1 smooth transition feasible to 8 x 1035cm-2sec-1(50ab-1)

  27. KEK Roadmap: Belle Upgrade in 3 years shutdown Issues 4Higher background ( 20) 4Higher event rate ( 10) 4Require special features • radiation damage and occupancy • fake hits and pile-up noise in the EM - higher rate trigger, DAQ and computing • low p m identification f smm recon. eff. • hermeticity fn “reconstruction” Possible solution: 4Replace inner layers of the vertex detector with a silicon striplet detector. 4Replace inner part of the central tracker with a silicon strip detector. 4Better particle identification device 4Replace endcap calorimeter by pure CsI. 4Faster readout electronics and computing system.

  28. Belle detector upgrade Faster calorimeter with Wave sampling and pure CsI crystal Super particle identifier with precise Cherenkov device KL/m detection with scintillator and new generation photon sensors Background tolerant super small cell tracking detector New Dead time free readout and high speed computing systems Si vertex detector with high background tolerance New ideas are welcomed !

  29. New experimental group • It will be practical to build new detector by upgrading existing Belle. • However, the experimental group will be a new group, not an extension of the present Belle collaboration. • New participants are all welcomed and have equal opportunities to work on detector construction and physics. • It is welcomed to join the new group, but not Belle. • Interim Steering Committee is being formed. First meeting is scheduled March 2008, inviting potential new collaborators.

  30. 2007 2008 2009 2010 2011 2012 10 1 4 7 10 1 4 7 10 1 4 7 10 1 4 7 10 1 4 Experiment at KEKB KEKB/Belle upgrade TDR Detector Study Report (March 08) Final detector design (April 09) 2007 2008 2009 10 11 12 1 2 3 4 5 6 7 8 9 10 11 12 1 2 3 4 Detector proposals Internal review BNM (January 08) Pre kick-off meeting (19,20 March 08) Kick-off meeting (3,4 July 08) Meeting plan One-day general meeting and an IB meeting at every BGM Actions to invite new collaborators

  31. Summary • KEKB/Belle and PEP-II/BaBar have been running very successfully, and brought important scientific and technical achievements. • Next generation e+e-B factory with L~1036 will be very useful to study the new sources of flavor mixing and CP violation. • Search for new CPV in bgs transition • Very precise test of CKM scheme • Search for lepton flavor violating t decays • Studies of H±interactions with fermions • Very precise measurements of aS(@10GeV), sin2qW(@10GeV)… • KEK Roadmap includes KEKB upgrade. • KEKB machine upgrade plan  Onishi’s talk • Detector upgrade necessary to improve BKG/rate immunity. • New collaboration to be formed soon.

  32. Roadmap: comment Our final goal of the integrated luminosity is 50/ab in the new experiment at the upgraded KEKB. However, we did not include the full upgrade of the machine in the KEK's roadmap, due to the financial constraint in the lab. We will upgrade the fundamental part of the accelerator in the first three years, followed by incremental installation of the RF systems over several years to increase the beam current and the luminosity. The initial goal, 10/ab, will be achieved in the five years of operation after resuming the experiment. It should be noted that the plan up to this point is included in the KEK's roadmap. Then, considering the results of this experiment and LHC as well as progress of ILC and others carefully, we will decide if we propose further installation of the RF system to achieve the final goal, 50/ab, in the next five years.

  33. Precision test of KM scheme M.Pierini CKM2006

  34. Search for new flavor mixing l + l - : Probe the flavor changing process with the “EW probe”. g, Z0 b quark s quark This measurement is especially sensitive to new physics such as SUSY, heavy Higgs and extra dim. ? Theoretical predictions for l +l - forward-backward charge asymmetry for SM and SUSY model with various parameter sets. Possible observables: • 4Ratio of branching fractions • 4Branching fraction • 4CP asymmetry • 4q 2 distribution • 4Isospin asymmetry • 4Triple product correlation • 4Forward backward asymmetry • 4Forward backward CP asymmetry The F/B asymmetry is a consequence of g-Z0 interference.

  35. Search for new CP phases In general, new physics contains new sources of flavor mixing and CP violation. 4In SUSY models, for example, SUSY particles contribute to the bs transition, and their CP phases change CPV observed in BfK, h’K etc. U-KEKB SM SUSY contribution In general, if SUSY is present, the s-quark mixing matrix contains complex phases just as in the Kobayashi-Maskawa matrix. T.Goto et al., 2007

  36. Background & TRG rate in future x20 Bkg x10 Bkg KEKB Bkg SVD CDC PID / ECL KLM Shynchrotoron radiation Beam-gas scattering (inc. intra-beam scattering) Radiative Bhabha

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