Download presentation
Presentation is loading. Please wait.
Published byCalvin Barnell Modified over 9 years ago
1
B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul Overview of (selected) Belle and BaBar results B. Golob, Belle Collaboration University of Ljubljana Jožef Stefan Institute, Ljubljana Introduction Experimental environment overview CKM Matrix Phase - 1 ( ) - 2 ( ) - direct CPV Magnitudes - |V ub | Hadron spectroscopy New charm states much more… Conclusions
2
V ud V us V ub V cd V cs V cb V td V ts V tb (0,0) (0,1) Introduction B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul BaBar & Belle (Ba/lle) main task: CP violation in system of B mesons specifically: various measurements of complex elements of Cabbibo-Kobayashi-Maskawa matrix CKM matrix is unitary deviations could signal processes not included in SM (NP) W±W± qiqi qjqj V ij 1- 2 /2 A 3 ( - i ) A 2 1- 2 /2 - 1 -A 2 A 3 (1- -i ) = V ud V ub * V cd V cb * V td V tb * V cd V cb *
3
B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul Experimental environment Asymmetric B factories ~1 km in diameter Mt. Tsukuba KEKB Belle Υ(4s) e+e+ e-e- BaBar p(e - )=9 GeV p(e + )=3.1 GeV =0.56 Belle p(e - )=8 GeV p(e + )=3.5 GeV =0.42 B B z ~ c B ~ 200 m L peak = =13.9x10 33 s -1 cm -2 253 fb -1 274 M BB L peak = =9.2x10 33 s -1 cm -2 221 fb -1 239 M BB √s=10.58 GeV Υ(4s)
4
B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul Experimental environment-detectors Belle SVD: ~55 m (SVD1) ~40 m (SVD2) combined particle ID (K ± )~85% (p ± → K ± )<~10% @ p<3.5 GeV/c / K L detection 14/15 lyr. RPC+Fe Central Drift Chamber small cell +He/C 2 H 5 CsI(Tl) 16X 0 Aerogel Cherenkov cnt. n=1.015~1.030 Si vtx. det. 3 lyr. DSSD TOF conter SC solenoid 1.5T 8 GeV e - 3.5 GeV e + z-imp.param. resolution BaBar:DIRC Cherenkov angle p
5
B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul CKM Matrix – phases Measurement method B CP B tag J/ KsKs ++ -- -- ++ K-K- l-l- Fully reconstruct decay to CP eigenstate Tag flavor of other B from charges of typical decay products t= z/ c Determine time between decays CPV manifests as an asymmetry in time dependent decay rates SM: for b → ccs : S=sin2 1, A=0 Υ(4s) 11 determined B 0 (B 0 ) B 0 or B 0
6
B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul CKM Matrix – sin2 1 N sig =4150 to isolate B → f CP decays from bckg. B→J/ K s 274M BB T. Higuchi ICHEP’04 227M BB M.Bruinsma ICHEP’04 B→J/ K L J/ψ K L signal J/ψ X background Non-J/ψ background B A B AR N sig =2788 determine t distribution
7
CKM Matrix – sin2 1 B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul t [ps] -8 8 Difference between B 0 and B 0 tagged decays Miss-tagging probability w reduces asymmetry by 1-2w Expected t distribution convolved with detector resolution function S=sin2 1 = 0.666 ± 0.046 T. Higuchi,ICHEP’04 Belle S=sin2 1 = 0.722 ± 0.040 ± 0.023 M.Bruinsma,ICHEP’04 BaBar (A=0 fixed) (A=0.023 ± 0.031) a CP B tag =B 0 11
8
CKM Matrix – sin2 2 B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul B 0 → S = √(1-A 2 )sin2 2 eff A ~ sin P function of 2 1 P |P/T| Constraint: SU(2) symmetry M +0 = 1/√2 M +- + M 00 M -0 = 1/√2 M +- + M 00 b d W+W+ u d d u B0B0 T ~ V ub *V ud ~ 3 ++ -- S=sin2 2 A=0 b d d u u d b d W+W+ u u d d P ~ V tb *V td ~ 3 t B0B0 ++ -- B0B0 00 00 W+W+ T c ~ V ub *V ud 22
9
CKM Matrix – sin2 2 B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul 152M BB PRL93,021801(2004) good tag B 0 → S +- = -1.00 ± 0.21 ± 0.07 A +- = 0.58 ± 0.21 ± 0.07 S +- = -0.30 ± 0.17 ± 0.03 A +- = 0.09 ± 0.15 ± 0.04 227M BB Babar,M.Cristinziani,ICHEP’04 -A +- S +- M.A.Giorgi, ICHEP’04 B 0 → a CP t [ps] N sig =232 N sig =467
10
CKM Matrix – sin2 2 B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul B 0 → M bc [GeV] Br(B 0 → 0 0 ) = (1.17 ± 0.32 ± 0.10)x10 -6 A CP = 0.12 ± 0.56 ± 0.06 227M BB Babar,M.Cristinziani,ICHEP’04 274M BB Belle,Y.Sakai,ICHEP’04 Br(B 0 → 0 0 ) = (2.32 ± 0.45 ± 0.20)x10 -6 A CP = 0.43 ± 0.51 ± 0.17 Similar analysis as for B → also for B → ( 2 eff closer to 2 ) S +- Br(B 0 → 0 0 ) A +- Br(B 0 → + - ) A CP Br(B + → + 0 ) Ba/lle BaBar Similar from B → Ba/lle Similar from B → 2 = 106 o ± 8 o 11 o M.A.Giorgi,ICHEP’04 N sig =61 N sig =82
11
CKM Matrix – direct CPV B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul ≠0 direct CPV; |M(B→f)| ≠|M(B→f)| only when multiple proc. contribute to f (tree+penguin) Belle B→ + - first evidence A +- = 0.58 ± 0.21 ± 0.07 not confirmed by BaBar Direct CPV also in time integrated decay rates: 5.20 5.24 5.28 M bc B 0 →K - + B 0 →K + - A CP = -0.133±0.030±0.009 A CP = -0.101±0.025±0.005 BaBar,227M BB,M.A.Giorgi,ICHEP’04 Belle,274M BB,Y.Sakai,ICHEP’04 N sig =2139 N sig =1606
12
CKM Matrix – consistency B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul Many independent measurements Unitary |V ub /V cb | B X c,u l W From tree-level (s.l.) B decays b c,u |V cb | known to ~1.4%, becoming as precise as |V us |= (~1%) need to pin-down |V ub |, present WA acc. ~10% b→cl backg. order of magnitude larger
13
CKM Matrix – |V ub | B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul l ElEl q2q2 MXMX B Variables separating b → ul from b → cl lepton energy E l ; hadronic inv. mass M x ; leptonic inv. mass q 2 ; B1B1 B2B2 (4s) D K l XuXu fully reconstructed (M bc ) To reduce theoretical uncertainty in Br(b→ul ) ↔ |V ub | use combination M x - q 2 Full reconstruction Belle: B→D (*)- + / + /a 1 + /D s (*)+ ~0.25% BaBar: B→D (*)- n 1 n 2 K … ~0.4% Babar,88M BB high p lepton M bc [GeV] |V ub |
14
CKM Matrix – |V ub | B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul Extract signal in high q 2 low M x region: Babar-CONF-04/11,ICHEP’04 M x <1.7 GeV Belle,152M BB T.Iijima,ICHEP’04 q 2 >8 GeV 2 signal b→cl |V ub |= ( 4.98 ± 0.40 ± 0.39 ± 0.47)x10 -3 |V ub |= ( 5.54 ± 0.42 ± 0.50 ± 0.55)x10 -3 Babar Belle (stat.) (syst.) (th.) N sig ~115 N sig =174
15
CKM Matrix – back to sin2 1 B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul 11 Not only from b → ccs (B→ J/ K s ) b d W+W+ s s s d P ~ V tb *V ts ~ A 2 t B0B0 KSKS also from b → sss (B→ K s ) other proc. negligible S=sin2 1 B→KsB→Ks sin2 1 = 0.06 ± 0.33 ± 0.09 a CP 2.2 away from ccs N sig =139 sin2 1 = 0.50 ± 0.25 ± 0.06 Belle, 274M BB, Y.Sakai,ICHEP’04 BaBar,227M BB, A.Hoecker,ICHEP’04 M bc tt (0.73±0.04)
16
CKM Matrix – back to sin2 1 B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul other examples of b → sss (e.g. B → ’ K s ) 0.41±0.11 0.34±0.21 0.73±0.04 conservative upper bound: |S Ks -S ’KS |<0.2 Grossman et al. “sin2 1 ” S ’KS or S KS at present value would be sign of NP K s ’K s J/ K s
17
Conclusions B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul Aleph+Delphi BaBar+Belle CPV in K system new charm states direct CPV in B system Ba/lle mature exp., testing SM with high precision 1964: CPV in K system, 2001: CPV in B system 2004: sin2 1 ( ) is a precision measurement (±6%) 1999: direct CPV in K system, 2004: direct CPV in B system; CKM predictions confirmed 2 ( ) measured many measurements stat. limited, in 2 years ~2x more data J/ (c quark) CPV in B system direct CPV in K system
18
Conclusions B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul Before (B-factories)…: …and today…
19
Hadron spectroscopy – X(3872) B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul Belle observed a new state decaying into J/ X(3872) ’’ B + →K + X(3872) J/ l+l-l+l- M(J/ )- M(J/ ) [GeV] confirmed by CDF,D0,BaBar Belle: (X → c1 )/ (X→ J/ )<0.89 (X → c2 )/ (X→ J/ )<1.1 X(3872) not observed in any other decay mode Mass, width, Br’s & helicity un-compatible with expected cc states X(3872) M D* +M D 2M D cc J/ c0 c1 c2 hchc ’’ c ’’ hc’hc’ c1 ’ c2 Isospin 0++ allowed Isospin 1-- violating Decay to J/ + - < 1 MeV/c 2
20
Hadron spectroscopy – X(3872) B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul Search for B + →K + X(3872) J/ N=10.0±3.6 S/N=5 mass region M( )+M(J/ )=3879 MeV X(3872) → J/ could occur via virtual Belle,274M BB F.Fang,ICHEP’04 in accordance with DD* molecule model ( J )/ ( J/ )=0.8±0.3±0.1 Swanson,PLB 588,189(2004)
21
Hadron spectroscopy – D sJ mesons B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul BaBar and Cleo discovered two narrow resonances D sJ (2317) + → D s + 0 D sJ (2460) + → D s + , D s * + 0 BaBar, 125fb -1,V.Halyo,ICHEP’04 M(D sJ ) [GeV] J=1 J=2 J=1 J=0 D sJ (2317) + → D s + 0 D sJ (2460) + → D s + Properties studied e.g. helicity in B→DD sJ Belle,280M BB, M.Danilov,ICHEP’04 Apart from low masses properties in accordance with lowest level P states J P =0 +,1 +
22
Hadron spectroscopy – D sJ mesons B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul First observation of B 0 →D sJ (2317) + K - M(D s 0 )-M(D s ) [GeV] Events in M bc, E signal region B 0 →D sJ (2317) + K - B 0 →D sJ (2317) - + Measured branching fractions Br(B 0 -> D s K - )= (2.93±0.55 ± 0.79)x10 -5 Br(B 0 -> D s + )= (1.94 ± 0.47 ± 0.52)x10 -5 Br(B 0 →D sJ (2317) + K - )=(5.3±1.4±0.5±1.4)x10 -5 Belle,152M BB,A.Drutskoy,ICHEP’04
23
Conclusions B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul Aleph+Delphi BaBar+Belle CPV in K system new charm states direct CPV in B system Ba/lle mature exp., testing SM with high precision 1964: CPV in K system, 2001: CPV in B system 2004: sin2 1 ( ) is a precision measurement (±6%) 1999: direct CPV in K system, 2004: direct CPV in B system; CKM predictions confirmed 2 ( ) measured many measurements stat. limited, in 2 years ~2x more data J/ (c quark) CPV in B system direct CPV in K system
24
Continuum suppression backup slide continuum Y (4S) e + e - → qq “continuum” (~3x BB) e+e+ e-e- e+e+ e-e- qq Signal B Other B Continuum Jet-like BB spherical To suppress: use event shape variables
25
CKM Matrix – sin2 1 backup slide b q1q1 q2q2 q3q3 V q3b V* q2q1 W b q2q2 q2q2 q1q1 V qb V* qq1 q W g Tree QCD penguin sin2 1 ( ) CP asymmetry: CP in decay: |A/A| ≠ 1 CP in mixing: |q/p| ≠ 1 CP in interference between mixing and decay: | | = 1, Im( ) ≠ 1 | | ≠ 1 SM: |q/p|-1~ 4 (m c 2 /m t 2 )sin 1 ~5x10 -4 in B system | | ≠ 1 signals direct CPV
26
CKM Matrix – sin2 1 backup slide b → ccs: tree + penguin contribution ~ V cb V cs *=A 2 penguin only contribution ~ V ub V us *=A 4 ( -i ) (q/p) B A/A (q/p) K level of hadronic uncertainty due to interference (direct CP)
27
CKM Matrix – sin2 1 backup slide CP sampleN TAG purityη CP J/ψ K S (K S →π + π - )275196% J/ψ K S (K S →π 0 π 0 )65388% ψ(2S) K S (K S →π + π - )48587% χ c1 K S (K S →π + π - )19485% η c K S (K S →π + π - )28774% Total for η CP =-1437092% J/ψ K *0 (K *0 → K S π 0 )57277%+0.51 J/ψ K L 278856%+1 Total773078% BaBar, decay modes used: sin2β = 0.722 0.040 (stat) 0.023 (sys) Fit result with | |=1 fixed when left free: |λ|=0.950 ± 0.031 (stat.) ± 0.013 Miss-tagging probability, resolution function: from self-tagged events B →D*l, D , … Fitting function: BaBar: S A
28
B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul CKM Matrix – sin2 1 yield signal region J/ψ K L signal J/ψ X background Non-J/ψ background B A B AR 227M BB M.Bruinsma ICHEP’04 274M BB T. Higuchi ICHEP’04 B→J/ K s B→J/ K L N sig =4370 N sig =2788 N sig =4150 N sig =2722 to isolate B → f CP decays from bckg.
29
CKM Matrix – sin2 1 backup slide from b→sss penguin contribution ~ V cb V cs *=A 2 another penguin contribution ~ V ub V us *=A 4 ( -i ) S~sin2 1, theor. clean “sin2 1 ”= -0.96 0.51 152M BB, PRL91,261602(2003) S = 0.06 ± 0.33 ± 0.09 274M BB, ICHEP’04 2.2 away from ccs
30
CKM Matrix – sin2 1 backup slide S = 0.50 ± 0.25 ± 0.06 227M BB, ICHEP’04 2.7 away from ccs 2.4 away from ccs conservative upper bound: |S Ks -S ’KS | <0.2 Grossman et al. ’K s average: 0.41±0.11 K s average: 0.34±0.21 S ’KS or S KS at present value would be sign of NP
31
CKM Matrix – 2 backup slide u,c,t M +- = -Te -i 2 + Pe i P M +0 = 1/√2(T c e i C + T)e -i 2 M 00 = 1/√2(T c e i C e -i 2 + Pe i P ) S = √(1-A 2 )sin2 2 eff A ~ sin P b d W+W+ u d d u B0B0 T ~ V ub *V ud ~ 3 ++ -- S=sin2 2 A=0 b d d u u d b d W+W+ u u d d P ~ V tb *V td ~ 3 B0B0 ++ -- B0B0 00 00 W+W+ T c ~ V ub *V ud Ispospin relations for B→ 2 from B→ BaBar
32
CKM Matrix – 2 backup slide B→ from BaBar could be mixed CP state, but observed to be almost pure CP=+1 122M BB, Moriond QCD’04 S long =-0.19±0.33±0.11 A long = 0.23±0.24±0.14 89M BB, PRL91(2003),171802 Br(B + → )=(22.5±5.6±5.8)x10 -6 227M BB,M.A.Giorgi,ICHEP’04 Br(B 0 → ) < 1.1x10 -6 @90% CL 2 from B→ BaBar B→( from Ba/lle not CP eigenstate, 4 amplitudes considered:
33
CKM Matrix – 2 backup slide Decay time distribution: indirect CPV parameter ( 2 ) direct CPV parameter (B 0 → )+ (B 0 → ) (B 0 → )+ (B 0 → ) strong phase diff. between amplitudes asymmetry between direct CPV asymmteries Belle: selected bands BaBar: assume 3 dominated by +,-,0 and fit Dalitz plot
34
CKM Matrix – 2 backup slide M.A.Giorgi,ICHEP’04
35
CKM Matrix – direct CPV backup slide B→K ± 0 A CP = 0.04 ± 0.05 ± 0.02 274M BB,Y.Sakai,ICHEP’04 c.f. in B→K + - A CP = -0.101±0.025±0.005 2.4 diff. _d_d KK u u BB b d A CP = 0.06 ± 0.06 ± 0.01 BaBar,M.Chrintinziani,ICHEP’04 B - →K - 0 B + →K + 0 Large EW penguin?
36
CKM Matrix – direct CPV backup slide u,c,t b d W-W- u u s d K-K- ++ B0B0 P ~ V tb *V ts ~ A 2 b d W-W- u s d u B0B0 T ~ V ub *V us ~ A 4 K-K- ++ Contributions to B 0 →K - +
37
CKM Matrix – 3 backup slide b u W-W- u s d c B-B- T ~ V cb *V us ~ A 3 K-K- D0D0 b u u u c s B-B- K-K- W-W- T c ~ V ub *V cs ~ A 3 ( +i ) ~ e i 3 D0D0 Basic idea: use B - →K - D 0 and B - →K - D 0 with D 0,D 0 →f interference ↔ 3 Gronau,London,Wyler, 1991: B - → K - D 0 CP Atwood,Dunietz,Soni, 2001: B - → K - D 0( * ) [K + - ] Belle;Giri,Zupan et al., 2003: B - → K - D 0( * ) [K s + - ] Dalitz plot or any other common 3-body decay; Dalitz density depends on 3 Sensitivity depends on
38
CKM Matrix – 3 backup slide Belle: Use continuum D 0 from D *– D 0 π –, D 0 K s π + π – decay to model Dalitz plot density. E M bc B ± D 0 K ± D 0 K s π + π – B ± D 0 ± miss-id B + D 0 K + M 2 (K s + ) M 2 (K s - ) B - D 0 K - M 2 (K s + ) M 2 (K s - ) Belle,152M BB A.Bozek,ICHEP’04 Visible asymmetry Fit with 3, ,r B free 26 o < 3 < 126 o @ 95% C.L. r B = 0.26 ± 0.11 0.15 ± 0.03 ± 0.04
39
CKM Matrix – 3 backup slide BaBar,211M BB G.Cavoto,ICHEP’04 33 rBrB 68% 90% 33 rBrB 97% 74% 20% Belle,152M BB A.Bozek,ICHEP’04
40
CKM Matrix – |V ub | backup slide large non-perturbative corr. (large th. uncertainty) q2q2 Mx2Mx2 used in measurement (q 2 cut,M Xcut ) 8 GeV 2, 1.7 GeV V ub 6%-9% only q 2 cut 11.6 GeV 2 V ub 12%-15% C.W.Bauer et al.,hep-ph/0111387 |V ub |= ( 4.92 ± 0.39 ± 0.36 ± 0.46)x10 -3 |V ub |= ( 4.77 ± 0.28 ± 0.28 ± 0.69 0.39 )x10 -3 M X only M x -q 2 Babar-CONF-04/11,ICHEP’04
41
CKM Matrix – |V ub | backup slide |V ub |= ( 4.92 ± 0.39 ± 0.36 ± 0.46)x10 -3 M x -q 2 |V ub |= ( 5.54 ± 0.42 ± 0.50 ± 0.55)x10 -3 (stat.) (syst.) (th.) BaBar syst.: largest from detector (tracking, ID) and b→cl modeling Belle syst.: MC statistics BaBar Belle
42
X(3872) backup slide 35±7 events M=3872.0±0.8 MeV <2.3MeV (90%) M(J/ + -) BaBar
43
X(3872) backup slide c ” h c ’ c1 ’ 2 c2 3 M too low and too small angular dist’n rules out 1 J/ way too small c too small; (PRL 93, 2003) c should dominate J/ c & DD) too small - Isospin violating decays to J/ + - C(J/ )=-1,C( )=-1 → C(X)=+1 Since is not C eigenstate, decay X → J/ is probably X → J/ (as indicated by m( )) I( )=1, I( )=0, I(J/ )=0 → X decays break isospin symmetry ccuu=1/√2 cc [1/√2 (uu+dd)+1/√2 (uu-dd)]=1/√2(|I=0>+|I=1>)
44
D sJ backup slide Belle, 87fb-1,PRL92,012002(2004) M(D s 0 )-M(D s ) M(D s * 0 )-M(D s *) helicity angle: Feynman diagrams for B 0 →D sJ + K -
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.