1 / 66

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.

agatha
Download Presentation

Belle/KEB status & plans

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  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

More Related