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S. Nishida

SuperKEKB Physics Reach @ 50 ab − 1. S. Nishida. KEK. BNM2008. Jan. 24, 2008. Contents. Introduction B  D tn, tn Various Observable New CP Phase, Right-handed current, LFV Precise Measurement of Unitarity Triangle Summary. Introduction. B Factory. Super KEKB (plan).

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S. Nishida

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  1. SuperKEKB Physics Reach @ 50 ab−1 S. Nishida KEK BNM2008 Jan. 24, 2008

  2. Contents • Introduction • B  Dtn, tn • Various Observable • New CP Phase, Right-handed current, LFV • Precise Measurement of Unitarity Triangle • Summary

  3. Introduction

  4. B Factory Super KEKB (plan) Belle + BaBar > 1 ab-1 Target: 50 ab-1 (hopefully)

  5. Present CKM Measurement Kobayashi-Maskawa (KM) theory for the CP violation has been well confirmed. The role of Super B factory will be the study of New Physics (NP).

  6. Grand questions in flavor physics Why three generations ? Why masses and mixing parameters with strange patterns ? Why did antimatter disappear in the early universe ? ... The Standard Model (SM) does not give answers Profound principles (of Gauge, Relativity, Quantum) However, “Flavor Principle” is missing These exciting questions will remain unanswered even if SUSY is found at LHC. Flavor Physics Long-term step-by-step experimental approach in flavor physics needed to address these grand questions.

  7. Quark Flavor Physics by Hazumi

  8. Studies at Super KEKB • New CP-violating phases ? • tCPV in bs transition. • New right-handed currents ? • photon helicity in bs • Effects from new Higgs fields ? • B, D • New flavor violation ? • LFV () • New flavor symmetry to explain the CKM hierarchy ? • Precise unitarity triangle measurement • Direct detection of NP in flavor physics. • Measure properties of NP, if NP is found in LHC. • Constrain NP at higher energy scale (if NP not found).

  9. B, D Effect from new physics field

  10. “B Meson Beam” • By fully reconstructing one B meson,we can obtain “single B meson beam” • Approach unique at e+e- collider. • Powerful tool to study B meson decays to neutrino and tau. B e- e+  B p D full reconstruction 0.2~0.3% for B+ • |Vub| from semi-leptonic decays. • B  • B  D • B  K : 5 discovery with 33 ab-1.

  11. B  + b • Possible contribution of charged Higgs (H+) in tree level. • In the SM: • B(B) = (1.6 ±0.4)×10-4 H+? W+ B+ u t B decay constant Lattice QCD • More than 1 neutrinos in the final states (can be measured only in B factories). • fB and |Vub| should be known precisely.

  12. B  Belle result with 414 fb-1: Signal + background 0.56 0.49 0.46 0.51 B(B++) = (1.79 ±±)×10-4 Constrainton mH and tan plane: Background Btn Signal To estimate the charged Higgs mass reach at superB, experimental error is assumed to scale with luminosity.

  13. B  Prospects at 5 ab−1 and 50 ab−1 5 discovery region at 5 ab−1 5 discovery region at 50 ab−1 1000 1000 m(H) ~ 400 @ tan = 30 m(H) ~ 300 @ tan = 30 H± mass (GeV) H± mass (GeV) present exclusion region 0 0 100 100 tan tan fB = 5%, |Vub| = 5% fB = 2.5%, |Vub| = 2.5%

  14. B  95.5% exclude region at 5 ab−1 95.5% exclude region at 50 ab−1 1000 1000 m(H) ~ 545 @ tan = 30 m(H) ~ 353 @ tan = 30 H± mass (GeV) H± mass (GeV) 0 0 100 100 tan tan fB = 5%, |Vub| = 5% fB = 2.5%, |Vub| = 2.5% Note: The error from fB and |Vub| are comparable to experimental error. It is essential to reduce these errors to a few % level at 50 ab−1

  15. B  Dtn • Semileptonic decay (with t) • D/D ratio sensitive to charged Higgs. • Some sensitive observables (e.g.  polarization) • Good cross check for B tn • H-b-u vertex by B tn • H-b-c vertex by B  Dtn • H-b-t vertex by LHC directsearch tan =50 tan = 20 SM c.f.) BaBar 209 fb−1 tan =10 B(B  Dtn) = (0.86 ± 0.24 ± 0.11 ± 0.06)% 300 H± mass (GeV)

  16. B  Dtn Similar to Btn 50 ab−1 5 ab−1 Prospects 5 ab−1 B(B+D0+) : 7.9% MH > MWtanb/11 50 ab−1 B(B+D0+) : 2.5% MH > MWtanb/5

  17. Various Observables New CP phases in bs Right-handed current Lepton Flavor Violation

  18. New CP Phase in bs • Many New Physics models contains new source of CP violation. • bs transition is a good place to search for new CP phases. c w J/ b s , ’ b c t g B0 B0 W s s d d s KS/KL KS/KL d d sin2f1 reference (J/K0) is very clean: precision ~ 0.012 @50 ab−1

  19. New CP Phase in bs Present status: tree-penguin difference is now 0.1σ the difference is 2.2σ if we exclude this result: simple average is too naïve because the error is non-gaussian recent QCDF estimates need tomeasure mode by mode a few % uncertainty in good modes sin21eff-sin21

  20. Physics Reach in bs Sensitivity at superB is estimated based on Belle’s 492 fb−1 result. 50 ab−1 • present syst. error is categorised as reducible and irreducible error. 0.2 KSKSKS KS 0.02 ’KS

  21. Physics Reach in bs Expected asymmetry for J/KS(S=0.68) and KS(S=0.39) • SuperB can measure the deviation of O(0.01). • Understanding of hadronic uncertainty. 5 ab−1 50 ab−1

  22. Right-handed current mb ms ms mb • SM electroweak is purely left-handed. • photon from bsis almost left-handed. • Right-handed current is a signature of New Physics. • Interference of left- and right-handed amplitudes may lead to large mixing induced CP violation in radiative B decay. SM expectation S ~ −2(ms/mb)×sin2f1 Possible deviation from SM O(1): Warped extra dim. O(1): L-R symmetric model O(0.1): SUSY SU(5) NP with different chiral structure makes a large difference Note: strong interaction may enhance S up to 0.1 even in SM

  23. Right-handed current TCPV in B  KS0 at super B. TCPV in B  0 at super B. 1 Recent Belle result is not taken into account 1 K*0 S other KS0 S BF 1.3×10−6 0.5×10−6 0.1 0.1 KS0 total 0.1 10 50 0.1 10 50 Luminosity [ab−1] Luminosity [ab−1] S(0) = 0.15 @ 50 ab−1 S(KS0) = 0.03 @ 50 ab−1 Can reach to the level of hadronic uncertainty

  24. Right-handed current SuperKEKB (50/ab) S(BKS0) in SUSY general mixing framework dRL dRR Other exp. constraints (Bs mixing, Br(bsg)) taken into account J. Foster, K. Okumura, L.Roszkowski, for SuperKEKB physics book update

  25. Right-handed current Other analyses sensitive to right-handed current • B  K0+0, B  K+-0 • Angle between  and K plane (resonance dependent). • B  K* with   e+e- (conversion) • Angle btw K plane and e+e- plane. photon conversion analysis • angle resolution is estimated to be ~23 • efficiency ~0.36% (can be increased by adding more material) • measurement 2 ~ 4 level (even with maximal right-handed current) @ 50 ab−1 • need more study (e.g. adding low q2K*e+e- events)

  26. AFB in BK*ℓℓ, Xsℓℓ AFB (Forward-backward asymmetry) • Good electroweak probe for bs. • Sensitive to C7,C9, C10 Wilson coefficients. (c.f. wrong sign C7is allowed by bs) • q0 (the point with AFB=0)issensitive to New Physics. SM: q02 = (4.2±0.6) GeV2 q0 C7/Re(C9) AFB for bsℓℓ other variable: BF ratio btw K and Kee (>1 might be NP)

  27. AFB in BK*ℓℓ, Xsℓℓ 30 MC 20 Error(%) 10 C10 C9 5 5 ab−1 3 C7 1 10 100 C9, C10 q2 independent terms can be determined with accuracies of 11% and 14% (4% and 4%), respectively,at 5 ab−1(50 ab−1). Integrated Luminosity (ab−1) q0 ~ 11% (5%) Note: Xsℓℓ is better to avoid form factor uncertainty(experimentally challenging).

  28. bs and bsℓℓ at SuperB bd Many measurements sensitive to NP!! bs bs bd BXd @5 ab−1

  29. Lepton Flavor Violation Large LFV in  decay of O(10−7~10−9) in SUSY + Seesaw, SUSY GUTs . Br() etc. can be reached to O(10−7~10−9) in super B factory.

  30. SUSY Breaking at SuperB 1 2 3 4 T. Goto, Y.Okada, Y.Shimizu,T.Shindou, M.Tanaka, hep-ph/0306093, also in SuperKEKB LoI Representative SUSY scenarios a la SUGRA Similar SUSY mass spectra (hard to distinguish)

  31. SUSY Breaking at SuperB S(KS), S(KS0), ACP(bs), B(bs), B()..... useful to distinguish NP models.

  32. SUSY Breaking at SuperB “DNA Identification” of New Physics from Flavor Structure

  33. Precise Measurement of Unitarity Triangle

  34. Measurement of 2 B , ,  useful for measurement of 2 w d w +/+ d b +/+ b t g u B0 B0 u d u u d -/- -/- d d ACP(t) = S sin(mt) + A cos(mt) If there was no penguin diagram: S = -sin(22), A = 0 In reality, A 0 and (where  can be determined by isospin analysis)

  35. Measurement of 2 B  B  5 ab-1 5 ab-1 50 ab-1 50 ab-1 time-dependent isospin analysis

  36. Measurement of 2 B  5 ab-1 All combined 50 ab-1 50 ab-1 with S(00) ~ 1 @50 ab-1 • S(00) can be measured by using photon conversion (~0.23 @ 50 ab-1) • 8-fold  2-fold ambiguity.

  37. Measurement of 3 Methods to measure 3 • Time dependent analysis of B- D(*)- to measure sin(21+3). • B± D0CPK±(GLW method). • B- D(*)-K(*)-(ADS method). • Dalitz analysis of B± D(*)K(*)±. r (Cabibbo-suppressed / -favored ratio) needs to be input. Result depends on r. Theoretically clean (<1%), but dominanted by statisticseven with 50 ab-1 Good statistical power. D model from charm factories

  38. Unitarity Triangle 0.5 ab−1 (Belle)  (SuperBelle) 50 ab−1   0.5 ab−1 50 ab−1 

  39. Generic NP Constraints SuperKEKB (50 ab−1) Belle (~0.5 ab−1) 2d (rad) 2d (rad) rd2 rd2 Mixing amplitude: M = rd2MSMexp(-i2d)

  40. Before going to Summary

  41. Summary

  42. Summary a few % at 50 ab−1

  43. Summary

  44. Target at SuperB Present B factories have been provided many results. But, most results have been rather “rough”. • Observation of some modes, first measurement of…. • Typical error is O(10%) 0.5 ab−1 50 ab−1 ??? In Super B, we can/must perform O(1%) precision measurement. • This is a challenge. • Assumed “scale error to luminosity” doesn’t work without effort. • Smaller systematic (and theoretical) error everywhere. • But, a step to reach beyond the SM in flavor physics.

  45. Summary • Super KEKB pursues flavor physics • Precise measurement of Unitarity triangle • Information on New Physics • New CP phase in bs, right-handed current • Effect from Higgs (, D) • Lepton flavor violation .... • Useful to distinguish New Physics models. • Measurements complementary to LHCb. • With 50 ab−1, many measurements can reach to the level of theoretical (or unavoidable systematic) uncertainty. complementary to energy frontier expermients and essential to particle physics

  46. Backup

  47. Past News at Belle Observation of direct CP violation in B p+p- Evidence for B tn Observation of b  dg Evidence for direct CP violation in B  K+p- Beginning of b  s saga CP violation in B fKs, h’Ks etc. Observation of CP violation in B meson system Observation of B  K(*)ll Evidence for D0 mixing Exciting results every year !

  48. What is next with B 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.

  49. Role of SuperB LC LHC EDM LFV B physics K physics Muon g-2 Charm physics LHC will (hopefully) find some New Physics, but may not have enough information to determine the nature of New Physics. (Okada) Super B Factory provides many observables / clean measurements. • New CPV phase • Kll, K • Lepton flavor violation ( decay) “Synergy” with LHC (etc.) The information will be essential to distinguish various New Physics senarios. The Super B may find New Physics but may not have enough information to determine its nature, In this case, the LHC and linear collider may be needed to distinguish the underlying new physics model.

  50. B , e • PreciseB  / mnlepton universality test. • Higgs effect itself is universal. RHtn = RHmn • Good probe to distinguish NP models. SM Br(tn)=1.6x10-4 Br(mn)=7.1x10-7 Br(en)=1.7x10-11 ~50 events @ 5ab-1 ~500 events @ 50ab-1 3s at 1.6ab-1 5s at 4.3ab-1 Significance good discovery channel at an early stage of SuperKEKB Luminosity (ab-1)

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