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Belle/KEB status & plans

Belle/KEB status & plans. P5 meeting SLAC 10/5/05. S.L. Olsen U. of Hawai’i. φ 1 , φ 2 , φ 3 ; penguins; new particles;… +plans for Super-KEKB/Belle. The KEKB Collider ( 8 x 3.5 GeV, X angle ). L=(1.6 x 10 34 )/cm 2 /sec Int(L dt)= 469 fb -1 On- resonance~420fb -1. KEKB Collider.

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Belle/KEB status & plans

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  1. Belle/KEB status & plans P5 meeting SLAC 10/5/05 S.L. Olsen U. of Hawai’i φ1, φ2, φ3; penguins; new particles;… +plans for Super-KEKB/Belle

  2. The KEKB Collider (8 x 3.5 GeV, X angle) L=(1.6 x 1034)/cm2/sec Int(L dt)= 469 fb-1 On- resonance~420fb-1 KEKB Collider

  3. Status of Asymmetric B Factories Used this summer KEKB Ldt  2(t/14mo) PEP-II

  4. Normal injection Continuous injection 661/pb/day 1182 pb/day

  5. collaboration

  6. Detector performance Pt resolution (s in %) M(p0) resolution (s in MeV) (Bp+p-: s(DE)21MeV) (Bp0p0: sM(p0)8MeV) 4.5MeV 0.3% 1 GeV/c 100MeV 1 GeV

  7. Particle ID in Belle ~80% ~8%

  8. ~10% ~4% ~2% ~2% SVD Occupancy Present : layer 1 of SVD ~10%occupancy / 200 Krad.yr-1 SVD2 L~1.6x1034 → L~5x1034 cm-2s-1 ???

  9. DAQ upgrades Faster signal processing with CMS chip in SVD (Silcon vertex det.) w/o Event Builder Upgrade New pipelined data Acquisition system (COPPER) Present operation

  10. The B Factory Physics Program 1)Measure of Fundamental SM Params: CKM elements & phases 2)Search for New Physics: look for evidence of new particles in loops 3) Unanticipated new phenomena: large s(e+e-cccc), X(3872),Y(3940),.. 4) + lots of “bread & butter” hc’, cc2’, D**,Sc*, t-physics, spin frag-fcn,… Warning: I can only give a few small tastes from this rich & flavorful menu

  11. sin21from BfCP + BBfCPinterf. Sanda, Bigi & Carter: J/y Vcb B0 KS  V*2 td J/y V* Vtb td B0 B0 KS Vtb V* td

  12. Principle of CPV Measurement (B0 or B0 ?) J/ (r+) fCP KS (r-) z t=0 B - B B + B more B’s more B’s t z/(cβγ) = (1-2w)sin21 = (1-2w)sin21

  13. _ 2005: B0 J/y K0 w/386 M BB pairs B0 J/y KS 0 B0 J/y KL 0 Nsig = 5264 Purity 98 % CP odd Nsig = 4792 Purity 60 % CP even

  14. CP side:s(Dt)0.5ps tag side:s(Dt)0.9ps

  15. _ _ B0 tag 2005: B0 J/y K0 sin2f1= 0.652 ±0.039 (stat) ±0.020 (syst) A = 0.010 ±0.026 (stat) ±0.036 (syst) B0 tag BG subtracted distributions (good tag region) previous result sin2f1= 0.728  0.061 (152 M BB pairs) _ consistent ~1.2s

  16. f1 measurement ? f1~70o sin2f1 ? f1~20o f1 2-fold ambiguity 2f1 p-2f1

  17. _ f-+ f+- M(KSp-) M(KSp-) M(KSp+) M(KSp+) B0  D0h0Belle’s New Method for Direct measurement of f1 (D0KSp+p-) AB0D0h0(Dt) = cos(DMDt/2) -ei2f1hh0 sin(DMDt/2)

  18. _ Reconstruction of B0  D[KSp+p-]h0 D0 p0 D0 w D0 h D*0 p0, h Nsig = 157 ±24 purity : 59% Nsig = 67 ±10 purity : 86% Nsig = 58 ±13 purity : 60% Nsig = 27 ±11 purity : 52% D*0 D0p0 D*  D0 pi0 D*pi0 : 22 +- 9 D*eta : 5+- 6 TOTAL Nsig = 309 ±31 purity : 63%

  19. Time-Dependent Dalitz fit results Belle preliminary -30o < f1 < 62o (95% C.L.)

  20. Implications of Time-dependent Dalitz analysis Consistent with B0J/yK* results cos2f1 = 0.87 ±0.75, hep-ex/0504046 ? f1~70o Disfavored >2s sin2f1 (^_^) ? f1~20o f1 2-fold ambiguity resolved !

  21. Experimental Situation for B+ - in 2004 BABAR 227M BB Belle152 M BB with 372±32 B0→p+p− events with 467±33 B0→p+p− events hep-ex/0501071 PRL 93, 021601 (2004) 5.2s CPV, First evidence for DCPV (3.2σ) Also ~3.2s difference between Belle and BaBar

  22. 2005 results: Bkg subtracted B+ - projections B0 tagged B0 tagged 4s signal for Direct CPV p+p− Yield p+p− ACP & DE-Mbc 2D fits to individual time intervals Dt (ps)

  23. 2005: Status of B+ - App Belle 275M Spp BABAR 227M ~2.3s difference between Belle and BABAR - App (Cpp ) Spp

  24. Belle’s measurement of ACP(B0 0 ) hep-ex/0408101 published in PRL 275M BBbar pairs

  25. CPV in B0r+r Similar to Bp+p, but in principle more complicated … B  VV: not a single CP eigenstate r+p+p0: wide resonance, two0’sin the final state. Three miracles: fL ~ 100%  CP » +1 B()NR and int. small B(r0r0) << B(r+r), B(r+r0) < 1.1 30  6 (26  6 ) x 10-6(HFAG Winter05) 2q A+-/ 2 small Penguin pollution (q ) A00 A+0

  26. 275M BB B0r+r signal continuum b  c signal b  u B = 24.42.2  x 10-6 Mpp Helicity 3.8 4.1 continuum continuum signal r pp fL= 0.951  0.033 0.039 0.029 0.031 [Belle-CONF-0545]

  27. 2005: Belle Results on CPV in B+- Preliminary (274  106 BB pairs) q=1 q=-1 Results: Low quality tag High quality tag No CPV φ2 is near 900

  28. Belle Constraints on 2 (α) B only B [hep-ex/0502035] &  combined at 90% CL at 90% CL

  29. s u K+ W u c Vcb D0 s u u + d + d B B Vub D0 * VudVub b b 2(a) * c Vtd Vtb Vus Vcs   W K+ 3(g) 1(b) u u Vcd Vcb * f3 () measurement Simple mixing CPV f3 (withBd ) + Tree Tree fCOM _ fCOM O(l3) O(l3) Interference of bc and bu diagrams

  30. r r Belle method for f3: Dalitz 3) fCOM= D0KSp+p- B+: obtain from tagged D0 (D*+ D0p+) sample |A2| |A1| B-: r = CPV: Asymmetry in Dalitz dist.: m+=m(Ksp+), m-=m(Ksp-)

  31. 275M BB BD(*) K(*), DKS +- 209 signal D0K D*0K D0K* 58 signal 36 signal [D0p0] [hep-ex/0411049] [hep-ex/0504013]

  32. f3 Results (Belle and BaBar) [hep-ex/0411049,0504013] f3 = 63 deg. 15 13 [hep-ex/0504039] (Non-trivial constraint)

  33. Current status CPV angles only: η=0.321±0.027 =0.193±0.57 consistent with constraints from measmts of lengths of sides only: η=0.342±0.022 =0.216±0.036 Simplistic(?) summation: f1+ f2+ f3 182o  ~20o

  34. SM with KM ansatz works remarkably well for tree-level processes

  35. Next step: use bs penguins Example: no KM phase f1 * Vtd , h’, K+K- , h’, K+K- + B B * Vtd f1 _ SM: sin2f1 =sin2f1 from BJ/y KS (bc c s) unless there are other, non-SM particles in the loop eff

  36. New physics in loops? Many new phases are possible in SUSY How New Physics contributes to bs “Internal Penguin”

  37. Belle 2005:

  38. Significant CP Violation in a bs penguin mode!!

  39. >>all systematically below sin(2b) >>QCD corrections : sin2b(penguin)>sin2b(tree) Many bs modes were studied: recent QCD factorization estimates : [Beneke, hep-ph/0505075] [Cheng,Chua,Soni, hep-ph/0506268] sin2φ1(penguin)-sin2φ1(tree)

  40. sin2f1(penguin) = 0.50  0.06 (HFAG’s “naïve average”) 0.4-

  41. EW penguins • B Kl +l - K*l +l - (loops with virtual t’s, W’s, & Z’s)

  42. 1st measurement of AFB(BK* l l) Interference btw  and Z AFB (Kl +l -) = 0.09  0.14 (stat) AFB(K*l +l -) = 0.56  0.13 (stat) already rules out some new physics scenarios

  43. signal qq K*g other B First Observation of bd  _ Addresses the same physics issue as Bs- Bs mixing (future Tevatron RunII goal).

  44. 68%CL r 95%CL Full UT fit Implications of Belle’s observation of bd  Same physics as Bs mixing

  45. bonuses: new mesons, many puzzles! Z(3931) cc2’? hc’ X(3872) Y(3940) not seen in s(e+e-hadrons) at Ecm =4.26 GeV e+e-cccc Y(4260) Y(4260) ??? hc”?? M(wJ/y) MeV

  46. Future

  47. KEKB near term • During the recent summer shutdown (2005) • one more RF station for ARES cavity (a klystron, low level control …) in HER (to be named as D5E) • Increase of the HER beam current by about 150mA • One RF station costs about 2 Oku-yen. • new movable masks in LER: Cu head • solenoids for electron cloud • Upgrade the 50 power supplies for solenoid coils (3A -> 5A) • test of thin coils inside quadrupole magnets • 3.5  3.27 (lower?) bucket spacing? • Crab cavity (Jan 2006) • A crab cavity for the purpose of raising the beam-beam parameters is scheduled to be installed in each ring at the beginning of 2006.

  48. Comparison of Specific Luminosity 3.5 bucket spacing 3.77 bucket spacing

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