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KEK 　高エネルギ , Tokyo 東京

Projektbericht BELLE. KEK 　高エネルギ , Tokyo 東京. Collaboration. Status BELLE Experiment. Neue Resultate Y(5S). HEPHY Physik-Analysen. SVD Upgrade bei BELLE. KEKB Collider. e -. e +. L peak = 1.56 × 10 34 cm -2 sec -1 design = 10 34 cm -2 sec. 8GeV. 3.5GeV. 500 fb-1. = 0.425. bg.

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KEK 　高エネルギ , Tokyo 東京

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  1. Projektbericht BELLE KEK　高エネルギ, Tokyo 東京 Collaboration Status BELLE Experiment Neue Resultate Y(5S) HEPHY Physik-Analysen SVD Upgrade bei BELLE

  2. KEKB Collider e- e+ Lpeak=1.56 × 1034cm-2sec-1 design=1034cm-2sec 8GeV 3.5GeV 500 fb-1 = 0.425 bg B-Factory (on the 4s resonance) BB threshold

  3. BELLE-Detector ECL CDC SVD KLM

  4. Power Supply F3 Power Supply B1 Power Supply B0 Power Supply B3 Power Supply F4 Power Supply F2 Power Supply F1 Power Supply B2 Power Supply B4 Power Supply F0 Dock B0 Dock B3 Dock F4 Dock B1 Dock F0 Dock F1 Dock B4 Dock B2 Dock F2 Dock F3 sensors sensors sensors sensors sensors sensors sensors sensors sensors sensors TTM S7 TTM S1 TTM S2 TTM S3 TTM S4 TTM S6 TTM S0 TTM S8 TTM S9 TTM S5 SVD front-end Inside End-cap Inside CDC Rad-Ctrl area E-Hut 1. S4 problem 2. S1 problem

  5. Prologue Oct.05 12 hybrids (S1) stopped working Oct.16 After a big earthquake, another 12 hybrids (S4) stopped working and recovered by itself by the next morning

  6. Burned connectors S1 S4 All the others in FWD also browned One in BWD (B4) slightly

  7. What should we do for BWD? We must replace the connector before being burned. Nobody knows when it will be. We don’t like to have fearful days so long. During the coming winter shutdown would be the best e.g. Dec.26~28 open end-yoke/end-cap Dec.26~28 cosmic ray runs Dec.29,30 take boards out Jan.04~09 repair boards and install, test Jan.09~12 cosmic ray runs Jan.10~12 close end-cap/end-yoke

  8. Y(5S) Number of Bs in dataset Lumi = 1.8574 fb-1 Y(5S) hadronic events bb continuum included bb events N ev =560,872 ± 3,018 ±28,630 fs = (16.4 ± 1.4 ± 4.1 )% Bs events N ev =91,983 ± 7,868 ±23,470 f(Bs*Bs*) = (93 ± 10)% Bs* Bs* channel N ev =85,544 ± 11,754 ±21,827 Bf(Bs->Ds+p- ) = (9 ± 3) / 85544 / 2/ (0.00808 ± 0.00103) = (0.65 ± 0.22 ± 0.21)% CDF : Bf(Bs->Ds+p- ) = (0.40 ± 0.06 ± 0.06 ± 0.11 ± 0.06 )%

  9. Y(5S) Number of bb events. Ncont(5S) = Ncont(E=10.519)* L(5S) / L(cont) * (Econt/E5S)2 Y(5S) : exp 43 runs 1013-1034 (5S scan excluded) N(hadron)= 6, 223, 974 events Lumi = 1.85740 ± 0.00100 (stat) fb-1 Cont : exp 43 runs 924-972 2 s ~ 1/Ecm N(hadron)= 11, 876,173 events Lumi = 3.66997 ± 0.00135 (stat) fb-1 (1.8574/3.66997)*(10.5189/10.869)2 = 0.4740± 0.0019 Corrections for HadronB cuts: 1. Nch >3 => ( 0.5 ± 0.3)% 2. E/Ecm > 0.18 => ( 0.2 ± 0.1)% R = s(hadrons) / s(mm) Nbb(5S) = ( 6223974 – 11876173 * 0.474 *1.007 ) / 0.99 = 560,872 ± 3,018 ±28,630 CLEO : 0.42 fb-1 Nbb(5S) = 130000 ± 1000 ± 22000 (events / lumi : ~2.5% larger) Status of Y(5S) analysis, BGM, Nov 15, A. Drutskoy

  10. Y(5S) Inclusive analysis : Y(5S) -> Ds X Theory : hep- ex/0508047 CLEO Y(5S) P/Pmax< 1 Bf (Bs DsX) = (92 ± 11) % PDG : Bf (Dsfp+)=(3.6 ± 0.9)% Babar : Bf(Dsfp+)=(4.8 ± 0.6)% Dsfp+ Sum: Bf(Dsfp+) = (4.4 ± 0.5)% 3775 ± 100 ev CLEO : Bf (B  DsX) = ( 9.0 ± 0.3 ±1.4)% Babar : Bf (B  DsX) = ( 8.94 ± 0.16 ± 1.12)% After continuum subtraction and efficiency correction: Bf (Y(5S)  Ds X) 2 = (22.6 ± 1.2 ± 2.8) % CLEO measured: Bf (Y(5S)  Ds X) / 2 = (22.35 ± 2.1 ± 4.95)% fs = (16.4 ± 1.4 ± 4.1 )% Syst. err. dominated by Bf(Dsfp+) => Using Ds mesons CLEO measured fs = (16.0 ± 2.6 ± 5.8 )%

  11. Y(5S) Exclusive Bs Ds(*)+p- decays Bs Ds+p- Bs Ds*+p- BsBs , Bs*Bs, Bs*Bs* MC 9 events in Bs* Bs* 4 events in Bs* Bs* Ds+ f p+ , Ds+ K*0 K+,Ds+ Ks K+ Clear signal at Bs* Bs* channel ; signals in Bs* Bs and BsBs channels are not seen. Cut on angle between Bs and beam direction was recently removed ( 1- 1- 1- ) (few more events).

  12. Y(5S) DE distribution, sum of all Bs decay modes 5.408< MBC<5.429 GeV/c2 5.384< MBC<5.405GeV/c2 Bs* Bs* Bs* Bs Nev=20.0 ± 4.8 6.7 s Small signal , Nev = 1.5 ± 2.0 (7±10%) Decay U(5S) -> Bs* Bs* , with Bs* -> Bsg. Potential models predict Bs* Bs* dominance over Bs*Bs and BsBs channels, but not so strong. DE peak = Ecm(accel.)/2 – Ecm(real)/2 – E(g) DE peak = – 47.6 ± 2.6 MeV

  13. Y(5S) MBC distribution, sum of all Bs decay modes - 0.08<DE<- 0.02 MeV - 0.08<DE<- 0.02 MeV Bs* Bs* Bs* Bs* Mbc = (E*B+DEpeak)2 – P*B2 Mbc = E*B2 – P*B2 M (Bs) = 5370 ± 1 ± 3 MeV/c2 Ecm = 10869 MeV ; E*B = Ecm/2 CDF: M (Bs) = 5366.0 ± 0.8 MeV/c2 M (Bs*) = 5418 ± 1 ±(acc. err) MeV/c2 Photon energy smearing does not change Bs mass position Photon momentum is neglected => does not change Bs* mass position, only smearing.

  14. HEPHY Physik-Analysen Christoph Schwanda: Momente der El und MX2 in BXc l n Laurenz Widhalm: Formfaktoren semileptonischer D° Zerfälle Heinz Dibon: Parallelanalyse als Cross-CheckFranz Mandl: BRs der inklusive Zerfälle D° fX/ K*X /r X Gerhard Leder: BRs der inklusive Zerfälle DsGerald Richter: Dekohärenz Modelle verschränkter B-Paare

  15. Christoph Schwanda

  16. Christoph Schwanda

  17. Christoph Schwanda

  18. Laurenz Widhalm K p p K p e/µ p p tag side: • reconstruction & fit of D0,± Kp, K2p, K3p • reconstruction & fit of D*0,± Dp, Dg • use either D or D* as primary meson signal side: • reconstruction & fit of inclusive D*0,± via recoil from e+e-  D(*) D*np/K • reconstruction & fit of inclusive D0 via recoil from D*  Dp • reconstruction & fit of neutrino via recoil from D  mpn Method of Reconstruction additional primary mesons e+ e- ( ) D* D* D g p p D n p K tag signal

  19. Laurenz Widhalm Summary of Signal / Background Decomposition D0 Ken D0 pen signal non-D bkg D0 Kmn D0 pmn hadronic bkg Kln bkg rln bkg mn² / GeV²

  20. Laurenz Widhalm Absolute Branching Ratios measured event numbers normalized to number of inclusive D0 efficiency corrected using the generic MC sample corrected for bias from differences in the multiplicity distribution MC/data reference hadronic channels as a cross-check

  21. Laurenz Widhalm f+(q²) = 1-q²/m²  Form Factors – Fit to Pole Model simple pole arbitrary normalization D0 Kln χ²/ndf=31/28 mKen=1.86 ± 0.06 GeV mKmn=1.78 ± 0.05 GeV f+(0)=0.704 ± 0.007 ± 0.010 mpen=2.01 ± 0.12 GeV mpmn=1.91 ± 0.08 GeV q² / GeV² arbitrary normalization D0 pln modified pole χ²/ndf=6/10 f+(q²)= (1-q²/m²) (1-aq²/m²)  f+(0)=0.628 ± 0.018 ± 0.026 mKen=2.15 ± 0.08 GeV mKmn=2.04 ± 0.06 GeV mpen=2.21 ± 0.17 GeV mpmn=2.07 ± 0.13 GeV = 0.50 (Kln) atheor. = 0.44 (pln)

  22. Laurenz Widhalm Current Status summer conference paper CONF-519 ready archived as hep-ex/0510003 gives relative BF‘s and form factors next step: journal publication will give absolute BF‘s and form factors second draft for PRL submitted to internal referees, waiting for response first reaction from theory side (A. Kronfeld, preliminary)

  23. Heinz Dibon

  24. Franz Mandl D0FX (1.7 ±0.8%) FK+K- (49.1±0.6%) D0 K+K- (0.389±0.015%) • BR(D0FX)= 269 0.389 ------- ----------- = 160 0.491 1.33±0.14%

  25. Gerhard Leder • Ds inklusiv T. Uglov at BGM

  26. Gerald Richter z1 , t1 μ+ z0 , t0 z2 , t2 The decay typical Υ(4S) resonance decay • βγcτB0 = 196 μm(LAB) l+ l- K0s π- entanglement region π+ θ 8 GeV e- 3.5 GeV e+ beam axis • Δm= 0.489 1012 ћs-1 = 0.754 τB0-1

  27. Gerald Richter Changing the parametrization new resolution function for t1, from double gaussian fit : t1 z abs resolution function for Δt, single gaussian : z abs Δt that should be on the safe side...

  28. Gerald Richter Parameter fit results the scatter of fitted λ parameters shows a dependence on the true parameters, that can be modeled.

  29. Electronic II From SVD 2.0 to SVD 2.5

  30. Electronic II From SVD 2.0 to SVD 2.5

  31. Electronic II

  32. Electronic II From SVD 2.0 to SVD 2.5

  33. Layer 1+2 replacement is scheduled in 2007 summer SVD3 schedule depends on approval of the project. SVD Upgrade SVD 2.5 Test R&D Prod. Test R&D Installation Prod.

  34. Franz Mandl line: e+e- D*+D*- MC (2 pr) red crosses: e+e- D*+D*-(0, + -) data (2, 3, 4 pr) arbitrary normalization ok for 3, 4 pr D0 K*0 X (signal) D0  h1X  h2X D0 KX M (K) at least one particle misidentified

  35. tag side Franz Mandl Inclusive Decays D0 K*0X and D0 0X Some time ago ( Fig) reported: B (D0 K*X) B (K*  K-+)  6.67%  B (D0  K*X)  10% Method: Full reconstruction of events: + 0, 1, 2 primary mesons e+e-  “right sign” signal side preliminary studies on efficiences etc have been reported (also for D0 0X) all particles “left over” in reconstruction should come from D0 (signal side) • ideal method for the determination of inclusive branching ratios for D0  hX, h = K*0, 0, , , ……. (not yet known)

  36. Franz Mandl not in PDG list “some time ago” K-+ effective masses of combinations of charged particles from kinematically selected D0 via recoil, tagging D*+D*-, D*+D*-0 and D*+D*-+- , …. events B(D0 K*X) *B(K*  K-+) =* 3.8% = 6.67% OLD

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