B  and  2 /  3 results from the B factories May 20, 2006 Sheldon Stone Syracuse Nobu Katayama (KEK)

20/05/2006 N. Katayama2 Outline  Belle B  result  Belle/BaBar  2 /  3 results  Super KEKB

20/05/2006 N. Katayama3 Search for B    B   is important for both SM and BSM.  Purely leptonic  Theoretically very clean  More than one ’s  Experimentally very challenging. B factories LEP First Evidence ! April 2006

20/05/2006 N. Katayama4 Signal Selection (1)  Reconstruct one B in hadronic decay modes   lepton is identified in the 5 decay modes.  Signal selection criteria  Signal-side efficiency including  decay br.  All selection criteria were optimized before examining the signal region (blind analysis). 81% of all  decay Modes are used  0.12% N + = 680k eff.= 0.29% purity = 57% N + = 680k eff.= 0.29% purity = 57%

20/05/2006 N. Katayama5 Signal Selection (2)  Extra neutral energy in calorimeter E ECL  Most powerful variable for separating signal and background  Total calorimeter energy from the neutral clusters which are not associated with the tag B Minimum energy threshold for single cluster  Barrel : 50 MeV  For(Back)ward endcap : 100(150) MeV Zero or small value of E ECL arising only from beam background Higher E ECL due to additional neutral clusters MC includes overlay of random trigger data to reproduce beam backgrounds.

20/05/2006 N. Katayama6 Signal validation  Extra neutral energy (E ECL ) is validated in the doubly tagged sample (control sample);  B tag is fully reconstructed  B sig is in semileptonic decay modes B +  D (*)0 X + (fully reconstruction) B -  D *0 B -  D *0 l - D 0  D 0  0 K -  + K -  + K -  +  -  + K -  +  -  + B+B-B+B-B+B-B+B- 494  18 B0B0B0B0B0B0B0B0 7.9  2.2 Total 502  18 Data458 Purity ~ 90%

20/05/2006 N. Katayama7 Background Estimation MC : 23.3  4.7 Data : 21 MC : 94.2  8.0 Data : 96 Large MC samples for e + e -  BB, qq, X u l, X u ,    , and rare B decays are used (including beam-background). Majority come from B  D (*) X l (~90%) + Xu l /rare (~10%). Sideband Total MC : 267  14 Data : 274 MC : 89.6  8.0 Data : 93 MC : 41.3  6.2 Data : 43 MC : 18.5  4.1 Data : 21

20/05/2006 N. Katayama8 Result: Opening the Box !  The signal regions are examined after finalizing all of the selection criteria. Observe excess in signal region ! 414 fb -1 # estimated background and observed events in the signal region

20/05/2006 N. Katayama9  The final results are deduced by unbinned likelihood fit to the obtained E ECL distributions. Fit Results Signal shape : Gauss + exponential Background shape : second-order polynomial Signal + background Background B   Signal  : Significance with systematics Observe 21.2 events with a significance of 4.2 

20/05/2006 N. Katayama10 B   Branching Fraction  Branching fractions are calculated by  All  decay modes combined Result is consistent with SM prediction within error Extracted branching fraction for each  decay mode SM : B(B   )=(1.59  0.40)×10 -4

2006/05/15 11 f B |V ub |, f B Extraction  Product of B meson decay constant f B and CKM matrix element |V ub |  Using |V ub | = (4.39  0.33)×10 -3 from HFAG f B =  GeV [HPQCD, Phys. Rev. Lett. 95, (2005) ] 14% 11% = 8%(exp.) + 8%(V ub )

Belle/BaBar  2 and  3 results

20/05/2006 N. Katayama13 Relative phase: ( B –  DK – ), ( B +  DK + ) includes weak ( φ 3 ) and strong ( δ ) phase.   : from B +  D 0 K + decay If D 0 and D 0 decay into the same final state, Need to use the decay where V ub contribution interferes with another weak vertex. B –  D 0 K – : Amplitude ratio:

20/05/2006 N. Katayama14 GLW method M. Gronau and D. London, PLB 253, 483 (1991); M. Gronau and D. Wyler, PLB 265, 172 (1991) СР eigenstate of D -meson is used ( D CP ). CP-even : D 1  K + K –, π + π – CP-odd : D 2  K S π 0, K S ω, K S φ, K S η … for D 1 for D 2 4 equations (3 independent), 3 unknowns Additional constraint: СР-asymmetry:  A 1,2 of different signs

20/05/2006 N. Katayama15 GLW method BaBar results (211 fb -1 ) hep-ex/ , hep-ex/ B  D CP+ K* 1.96±0.40± ±0.19±0.08 B  D CP- K* 0.65±0.26± ±0.40± ±0.10± ±0.12±0.04 R A -0.06±0.13±0.03 B  D CP- K 0.35 ±0.13±0.04 B  D CP+ K Belle results (253 fb -1 ) hep-ex/ B +  D 1 K + B -  D 1 K - B +  D 2 K + B -  D 2 K - New 1.17±0.14± ±0.16±0.05 RA -0.12±0.14±0.05 B D2KB D2KB D2KB D2K 0.06±0.14± ±0.14±0.05 B D1KB D1KB D1KB D1K 1.15±0.31± ±0.25± ±0.30± ±0.30±0.08 B D*2KB D*2KB D*2KB D*2K -0.20±0.22±0.04 B D*1KB D*1KB D*1KB D*1K

20/05/2006 N. Katayama16 ADS method D. Atwood, I. Dunietz and A. Soni, PRL 78, 3357 (1997); PRD 63, (2001) Enhancement of СР-violation due to use of Cabibbo-suppressed D decays B –  D 0 K – - color allowed D 0  K + π – - doubly Cabibbo-suppressed B –  D 0 K – - color suppressed D 0  K + π – - Cabibbo-allowed Interfering amplitudes are comparable 

20/05/2006 N. Katayama17 ADS method Belle results (350 fb -1 ) hep-ex/ Suppressed channel not visible yet: Using r D =0.060±0.003, for maximum mixing ( φ 3 =0, δ=180° ): r B <0.18 (90% CL) BaBar results (211 fb -1 ) hep-ex/ , hep-ex/ r B <0.23 (90% CL) for B  DK r B <0.16 for B  D*K

20/05/2006 N. Katayama18 Parameters are obtained from the fit to Dalitz distributions of D  K s π + π – from B ±  DK ± decays Dalitz analysis method Using 3-body final state, identical for D 0 and D 0 : K s π + π -. Dalitz distribution density: (assuming СР-conservation in D 0 decays) is determined from D *–  D 0 π –, D 0  K s π + π – decay  model uncertainty of the result A.Bondar, Proceedings of the Belle Workshop, September (2002) A.Giri, Yu. Grossman, A. Soffer, J. Zupan, PRD 68, (2003)

20/05/2006 N. Katayama19 ρ-ω interference Doubly Cabibbo suppressed K * M (GeV 2 ) K s π – 2 D 0  K s π + π – decay model D 0  K s π + π – decay model

20/05/2006 N. Katayama20 Dalitz analysis (BaBar) Combined for 3 modes: γ = 67  28  13(syst)  11(model)° BaBar results (211 fb -1 ) hep-ex/ , hep-ex/ B   DK  B   D*K  B   DK*  Model uncertainty from ππ s-wave estimated with K-matrix formalism: 3°. Nonresonant contribution to B   DK*  is treated by introducing additional free parameter 0< κ <1 accounting for B   DK S π  contribution.

20/05/2006 N. Katayama21 Dalitz analysis (Belle) Belle result (350 fb -1 ) 331±17 events 81±8 events 54±8 events B   DK  B   D*K  B   DK*  B-B- B+B+ B-B- B+B+ B-B- B+B+ New

20/05/2006 N. Katayama22 Dalitz analysis (Belle) Combined for 3 modes: φ 3 =  3(syst)  9(model)° 8 ° < φ 3 <111 ° (2σ interval) r DK =  0.012(syst)  0.049(model)° CPV significance: 78% r DK =  0.013(syst)  0.049(model)° r DK =  0.041(syst)  0.084(model)° φ 3 = °(stat) φ 3 = °(stat) φ 3 = °(stat) B   DK  B   D*K  B   DK*  New

20/05/2006 N. Katayama23 α/φ 2 : B  ρρ B 0   +  – has 3 polarization states with different CP eigenvalues Belle Fortunately, longitudinal polarization dominates, therefore, pure CP-even state BaBar (PRL 95, , (2005)): Belle (hep-ex/ ): cos  # of Events No significant  0  0 signal  small penguin contribution BaBar (PRL, 94, (2005)): New

20/05/2006 N. Katayama24 α = 100°±13° 79°< α <123° B  ρρ BaBar results (211 fb -1 ) φ 2 = 8 8°±17° 59°< φ 2 <115° PRL, 95, (2005)

20/05/2006 N. Katayama  B  ρπ (BaBar) BaBar results (192 fb -1 ) hep-ex/ Interference between the  resonances gives information on strong phases between resonances   can be constrained without ambiguity Time dependent Dalitz analysis assuming Isospin symmetry: –+–+ +–+– 0000 Signal MC CP asymmetries:  = ( −17 ± 6)º

20/05/2006 N. Katayama26 add new Belle  +   : B, S, A and new Babar  +  o : B, f L, A Note: Isospin triangle  does not close experimental error ?  2 = 97  5 deg.   combined   combined

20/05/2006 N. Katayama27 Angle Summary  2,  3 : Remarkable progresses have recently been made but they are still statistically limited Consistent with  1 +  2 +  3 = 180 o SM constraints  1 = (23  1)º  2 = (97  5)º  3 = (60 )º +5  4

20/05/2006 N. Katayama28 Super KEKB  Asymmetric energy e  e  collider at E CM =m(  (4S)) to be realized by upgrading the existing KEKB collider.  Super-high luminosity  8  /cm 2 /sec  10  10 9 BB per yr.  8  10 9     per yr.  8  10 9     per yr. Belle with improved rate immunity Higher beam current, more RF, smaller  y * and crab crossing  L = 8  /cm 2 /sec

20/05/2006 N. Katayama29  Are there New Physics phases and new sources of CP violation beyond the SM ?  Compare CPV angles from tree and loops.  Are there new flavor-changing interactions with b, c or  ?  b  s bar, D-Dbar mixing+CPV+rare,   Are there right-handed currents ?  b  s  CPV, B  V V triple-product asymmetries More questions in flavor physics Can we answer such questions at a Super B Factory? _d_d b s _s_s B  _d_d s KsKs

20/05/2006 N. Katayama30 Why∫ L dt = 50ab -1 is a goal?  Most of the interesting measurements will be limited by unavoidable systematics when we reach 50ab -1. sin2  1 22 33 |V ub | SKsSKs DCPV in b→s  Obs.  stat with 50ab -1  syst with 50ab -1 AKsAKs S’KsS’Ks A’KsA’Ks Theory err. ~ ºa few º 1.2ºO(1) º 1%~1%~5 %

20/05/2006 N. Katayama31 Proposed schedule Integrated luminosity (ab -1 ) Calendar year Belle is here. 0.58ab -1 Crab cavity installation 2 yr shutdown for upgrade L peak ~1.6× ×10 34 SuperKEKB ~4-8× B BB and     every year  Takes 250 years with present KEKB  8.2 years with L peak =4×10 35 : Super KEKB baseline design  3.3 years with L peak =1×10 36

20/05/2006 N. Katayama32 Comparison with LHCb e  e  is advantageous in… LHCb is advantageous in… CPV in B→  K S,  ’K S,… CPV in B→K S  0  B→K, , D (*)  Inclusive b→s , see  →  and other LFV D 0 D 0 mixing CPV in B→J  K S Time dependent measurements of B S B C and bottomed baryons Most of B decays not including or  B (S,d) →  They are complementary to each other !!

20/05/2006 N. Katayama33 How to achieve the super-high luminosity Crab cavity

20/05/2006 N. Katayama34 New parameter set for 8  10 35

20/05/2006 N. Katayama35 What ’ new in the param. set?  8  cm -2 s -1 is achievable with the same beam currents, beta and bunch lengths as before (4  cm -2 s -1 )  The beam-beam simulation was improved by using more longitudinal slices to reduce numerical noises and instabilities on a new super computer at KEK  A new choice of emittance (ratio or horizontal emittance)  Crab crossing (head on collision) is necessary  Crab waist, traveling focus may help lifetimes but not essential at this moment

20/05/2006 N. Katayama36 Accelerator R&D  Vacuum components for higher current  Antechambers, coating, bellows, collimetors,,  Superconducting quadrupoles  High power RF components  Bunch-by-bunch feedback system  C-band linac  Beam diagnostics  Crab cavities

20/05/2006 N. Katayama37 Interaction Region Crab crossing  =30mrad.  y *=3mm New QCS Components to be upgraded Linac upgrade More RF power Damping ring New Beam pipe

20/05/2006 N. Katayama38 Crab cavity: a new idea for higher luminosity  Head-on collisions with finite crossing angle !  avoid parasitic collisions  collisions with highest symmetry  large beam- beam parameter

20/05/2006 N. Katayama39  First performance report expected in fall 2006  Factor ~2 gain in L peak may be expected within ~2 yrs  ~3  cm  2 s  1 within our reach  First performance report expected in fall 2006  Factor ~2 gain in L peak may be expected within ~2 yrs  ~3  cm  2 s  1 within our reach fall We are here Now even more with better simulation!

20/05/2006 N. Katayama40 Super KEKB components Antechamber Bellows MO-flange C-band RF cavity

20/05/2006 N. Katayama41

20/05/2006 N. Katayama42 Requirements for the detector Issues 10~20 times more backgrounds

20/05/2006 N. Katayama43 Super Belle New Dead time free readout and high speed computing systems Faster calorimeter with Wave sampling and pure CsI crystal Super particle identifier with precise Cherenkov device Si vertex detector with high background tolerance Background tolerant super small cell tracking detector KL/  detection with scintillator and new generation photon sensors

20/05/2006 N. Katayama44 Summary of Super KEKB upgrade  Why? – Search for new sources of flavor mixing and CP violation  How? – Increase N B, decrease  y *, and crab crossing: L =8  /cm 2 /s  New beam pipe, crab cavity, new injector with damping ring  Belle will also be upgraded  Ideas for even higher luminosity and better detector are desperately needed  Please join and help!

20/05/2006 N. Katayama45 Systematic Uncertainty  Signal selection efficiencies  Tag reconstruction efficiency : 10.5% Difference of yields between data and MC in the B -  D *0 l - control sample Difference of yields between data and MC in the B -  D *0 l - control sample  Number of BB : 1%  Signal yield :  signal shape ambiguity estimated by varying the signal PDF parameters  BG shape : changing PDF  Total systematic uncertainty +12% -10% +17% -15%

20/05/2006 N. Katayama46 Dalitz analysis: sensitivity to the phase

20/05/2006 N. Katayama47 Model-independent approach A.Bondar, A.Poluektov hep-ph/ ab -1 at SuperB factory should be enough for model-independent γ/φ 3 Measurement with accuracy below 2° ~10 fb -1 at ψ(3770) needed to accompany this measurement. A.Giri, Yu. Grossman, A. Soffer, J. Zupan, PRD 68, (2003)