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Overview of (selected) Belle and BaBar results. B. Golob, Belle Collaboration University of Ljubljana Jo ž ef Stefan Institute, Ljubljana. Introduction Experimental environment overview CKM Matrix Phase - f 1 ( b ) - f 2 ( a ) - direct CPV
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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 - f1(b) • - f2(a) • - direct CPV • Magnitudes - |Vub| • Hadron spectroscopy • New charm states • much more… • Conclusions B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul
VudVub* VcdVcb* VtdVtb* VcdVcb* qi W± Vij qj Al3(r-ih) r h Al3(1-r-ih) Introduction 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) Vud Vus Vub Vcd Vcs Vcb Vtd Vts Vtb 1-l2/2 l f2(a) = Al2 1-l2/2 -l f3(g) f1(b) -Al2 1 (0,1) (0,0) B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul
Mt. Tsukuba KEKB Belle Lpeak= =13.9x1033 s-1cm-2 253 fb-1 274 M BB Lpeak= =9.2x1033 s-1cm-2 221 fb-1 239 M BB ~1 km in diameter B e+ e- Dz ~ cbgtB ~ 200mm B Experimental environment Asymmetric B factories √s=10.58 GeV Υ(4s) Υ(4s) BaBar p(e-)=9 GeV p(e+)=3.1 GeV bg=0.56 Bellep(e-)=8 GeV p(e+)=3.5 GeV bg=0.42 B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul
Experimental environment-detectors Aerogel Cherenkov cnt. n=1.015~1.030 SC solenoid 1.5T CsI(Tl) 16X0 3.5 GeV e+ TOF conter Central Drift Chamber small cell +He/C2H5 8 GeV e- m / KL detection 14/15 lyr. RPC+Fe Si vtx. det. 3 lyr. DSSD BaBar:DIRC Cherenkov angle p Belle SVD: ~55mm (SVD1) ~40mm (SVD2) combined particle ID e(K±)~85% e(p±→K±)<~10% @ p<3.5 GeV/c z-imp.param. resolution B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul
h f1 CKM Matrix – phases Measurement method r Btag B0 or B0 determined B0(B0) SM: for b → ccs : S=sin2f1, A=0 m+ Fully reconstruct decay to CP eigenstate m- J/y p- BCP Tag flavor of other B from charges of typical decay products p+ Ks l- Υ(4s) K- Dt=Dz/bgc Determine time between decays CPV manifests as an asymmetry in time dependent decay rates B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul
CKM Matrix – sin2f1 274M BB T. Higuchi ICHEP’04 227M BB M.Bruinsma ICHEP’04 BABAR Nsig=2788 J/ψ KL signal J/ψ X background Non-J/ψ background to isolate B→fCP decays from bckg. B→J/y KL B→J/y Ks Nsig=4150 determine Dt distribution B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul
CKM Matrix – sin2f1 Difference between B0 and B0 tagged decays Btag=B0 8 Dt [ps] -8 S=sin2f1= 0.666 ± 0.046 h f1 Belle T. Higuchi,ICHEP’04 S=sin2f1= 0.722 ± 0.040 ± 0.023 BaBar M.Bruinsma,ICHEP’04 r Expected Dt distribution convolved with detector resolution function Btag=B0 aCP Miss-tagging probability w reduces asymmetry by 1-2w (A=0.023 ± 0.031) (A=0 fixed) B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul
h CKM Matrix – sin2f2 f2 d d d r b b b u u p+ W+ u W+ p0 p+ u u W+ u B0 B0 B0 p- d d p- d d p0 d d T ~ Vub*Vud ~ l3 Tc ~ Vub*Vud P ~ Vtb*Vtd ~ l3 t S=sin2f2 A=0 Constraint: SU(2) symmetry M+0 = 1/√2 M+- + M00 M-0 = 1/√2 M+- + M00 B0→ p+ p-, p0 p0 S = √(1-A2)sin2f2eff A ~ sindP function of f2 f1 dP |P/T| B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul
CKM Matrix – sin2f2 152M BB PRL93,021801(2004) 227M BB Babar,M.Cristinziani,ICHEP’04 B0→ p+ p- -A+- good tag S+- B0→ p+ p- S+-= -1.00 ± 0.21 ± 0.07 A+-= 0.58 ± 0.21 ± 0.07 B0→ p+ p- S+-= -0.30 ± 0.17 ± 0.03 A+-= 0.09 ± 0.15 ± 0.04 Nsig=467 Nsig=232 aCP M.A.Giorgi, ICHEP’04 Dt [ps] B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul
CKM Matrix – sin2f2 227M BB Babar,M.Cristinziani,ICHEP’04 274M BB Belle,Y.Sakai,ICHEP’04 BaBar Ba/lle Similar from B → r r S+-Br(B0→p0p0) A+-Br(B0→p+p-) ACPBr(B+→p+p0) Ba/lle Similar from B → r p B0→ p0 p0 Br(B0→p0p0)= (1.17 ± 0.32 ± 0.10)x10-6 ACP= 0.12 ± 0.56 ± 0.06 Nsig=61 Nsig=82 Br(B0→p0p0)= (2.32 ± 0.45 ± 0.20)x10-6 ACP= 0.43 ± 0.51 ± 0.17 Mbc[GeV] (f2eff closer tof2) Similar analysis as forB → p p also forB → r r f2= 106o± 8o11o M.A.Giorgi,ICHEP’04 B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul
CKM Matrix – direct CPV ≠0 direct CPV; |M(B→f)| ≠|M(B→f)| only when multiple proc. contribute to f (tree+penguin) B0→K-p+ B0→K+p- BaBar,227M BB,M.A.Giorgi,ICHEP’04 Belle,274M BB,Y.Sakai,ICHEP’04 Belle B→p+p- first evidence A+-= 0.58 ± 0.21 ± 0.07 not confirmed by BaBar Direct CPV also in time integrated decay rates: Nsig=1606 Mbc 5.20 5.24 5.28 ACP= -0.133±0.030±0.009 ACP= -0.101±0.025±0.005 Nsig=2139 B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul
CKM Matrix – consistency l W n r h B Xc,u Many independent measurements Unitary D b c,u |Vub/Vcb| From tree-level (s.l.) B decays |Vcb| known to ~1.4%, becoming as precise as |Vus|=l (~1%) need to pin-down |Vub|, present WA acc. ~10% b→cln backg. order of magnitude larger B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul
h |Vub| CKM Matrix – |Vub| r g p K q2 D p B1 fully reconstructed (Mbc) B2 U(4s) l p l n El n p MX p Xu B Babar,88M BB high p lepton Mbc[GeV] Variables separating b → uln from b → cln: lepton energy El; hadronic inv. mass Mx; leptonic inv. mass q2; To reduce theoretical uncertainty in Br(b→uln) ↔ |Vub| use combination Mx -q2 Full reconstruction Belle: B→D(*)-p+/r+/a1+/Ds(*)+ e ~0.25% BaBar: B→D(*)- n1p n2K … e ~0.4% B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul
CKM Matrix – |Vub| Belle,152M BB T.Iijima,ICHEP’04 Extract signal in high q2 low Mx region: Babar-CONF-04/11,ICHEP’04 Mx<1.7 GeV q2>8 GeV2 signal b→cln Nsig~115 Nsig=174 Babar |Vub|= (4.98± 0.40 ± 0.39 ± 0.47)x10-3 (stat.) (syst.) (th.) Belle |Vub|= (5.54± 0.42 ± 0.50 ± 0.55)x10-3 B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul
h f1 CKM Matrix – back to sin2f1 s r Not only from b → ccs (B→ J/y Ks) b W+ also from b → sss (B→ f Ks) f s B0 d KS s d P ~ Vtb*Vts ~ Al2 t 2.2s away from ccs BaBar,227M BB, A.Hoecker,ICHEP’04 Belle, 274M BB, Y.Sakai,ICHEP’04 other proc. negligible S=sin2f1 sin2f1= 0.06 ± 0.33 ± 0.09 aCP B→fKs Nsig=139 (0.73±0.04) sin2f1= 0.50 ± 0.25 ± 0.06 Dt Mbc B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul
CKM Matrix – back to sin2f1 other examples of b → sss (e.g. B → h’ Ks) J/y Ks 0.73±0.04 f Ks 0.34±0.21 h’Ks 0.41±0.11 “sin2f1” conservative upper bound: |SyKs-Sh’KS|<0.2 Sh’KSorSfKS at present value would be sign of NP Grossman et al. B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul
direct CPV in B system new charm states CPV in B system direct CPV in K system CPV in K system J/y (c quark) BaBar+Belle Aleph+Delphi Conclusions • Ba/lle mature exp., testing SM • with high precision • 1964: CPV in K system, 2001: CPV in • B system • 2004: sin2f1(b) is a precision measurement (±6%) • 1999: direct CPV in K system, 2004: direct CPV in B system; CKM predictions confirmed • f2(a) measured • many measurements stat. limited, in 2 years ~2x more data B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul
h r r h Conclusions Before (B-factories)…: …and today… B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul
Hadron spectroscopy – X(3872) hc’’ < 1 MeV/c2 cc1’ hc2Y2 Y3 X(3872) hc’ MD*+MD Y’ 2MD cc2 hc cc1 cc0 Decay to J/Yp+p- Isospin 0++ allowed J/Y Isospin 1-- violating hc Mass, width, Br’s & helicity un-compatible with expected cc states Belle observed a new state decaying into J/yp+p- B+→K+ X(3872) confirmed by CDF,D0,BaBar J/yp+p- y’ l+l- X(3872) M(J/yp+p-)- M(J/y) [GeV] Belle: G(X→gcc1)/G(X→ J/yp+p-)<0.89 G(X→gcc2)/G(X→ J/yp+p-)<1.1 X(3872) not observed in any other decay mode B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul
Hadron spectroscopy – X(3872) Search for B+→K+ X(3872) Belle,274M BB F.Fang,ICHEP’04 J/yp+p-p0 N=10.0±3.6 S/N=5 in accordance with DD* molecule model w mass region M(w)+M(J/y)=3879 MeV X(3872)→w J/y could occurvia virtual w G(w J/y)/G(J/yp+p-)=0.8±0.3±0.1 Swanson,PLB 588,189(2004) B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul
Hadron spectroscopy – DsJ mesons BaBar, 125fb-1,V.Halyo,ICHEP’04 Properties studied e.g. helicity in B→DDsJ DsJ(2317)+ → Ds+p0 J=1 J=1 DsJ(2460)+ → Ds+g J=0 J=2 M(DsJ) [GeV] Belle,280M BB, M.Danilov,ICHEP’04 BaBar and Cleo discovered two narrow resonances DsJ(2317)+→ Ds+p0DsJ(2460)+→ Ds+g, Ds*+p0 Apart from low masses properties in accordance with lowest level P states JP=0+,1+ B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul
Hadron spectroscopy – DsJ mesons Belle,152M BB,A.Drutskoy,ICHEP’04 First observation of B0→DsJ(2317)+K- Events in Mbc,DE signal region Measured branching fractions Br(B0-> Ds K-)= (2.93±0.55±0.79)x10-5 Br(B0-> Dsp+)= (1.94±0.47±0.52)x10-5 B0→DsJ(2317)+K- B0→DsJ(2317)-p+ M(Dsp0)-M(Ds) [GeV] Br(B0→DsJ(2317)+K-)=(5.3±1.4±0.5±1.4)x10-5 B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul
direct CPV in B system new charm states CPV in B system direct CPV in K system CPV in K system J/y (c quark) BaBar+Belle Aleph+Delphi Conclusions • Ba/lle mature exp., testing SM • with high precision • 1964: CPV in K system, 2001: CPV in • B system • 2004: sin2f1(b) is a precision measurement (±6%) • 1999: direct CPV in K system, 2004: direct CPV in B system; CKM predictions confirmed • f2(a) measured • many measurements stat. limited, in 2 years ~2x more data B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul
Continuum suppression backup slide qq e- e+ Other B continuum Y (4S) e+ e- - BB Signal B Continuum Jet-like e+e- →qq “continuum” (~3x BB) BB To suppress: use event shape variables spherical
CKM Matrix – sin2f1 backup slide q1 q3 W V*qq1 b q b Vq3b q2 Vqb W q2 g V*q2q1 q2 q1 CP in decay: |A/A| ≠ 1 CP in mixing: |q/p| ≠ 1 CP in interference between mixing and decay: |l| = 1, Im(l) ≠ 1 |l| ≠ 1 Tree QCD penguin sin2f1(b) CP asymmetry: SM: |q/p|-1~ 4p(mc2/mt2)sinf1~5x10-4 in B system |l| ≠ 1 signals direct CPV
CKM Matrix – sin2f1 backup slide b → ccs: A/A (q/p)B (q/p)K level of hadronic uncertainty due to interference (direct CP) tree + penguin contribution ~ VcbVcs*=Al2 penguin only contribution ~ VubVus*=Al4(r-ih)
CKM Matrix – sin2f1 backup slide Fit result with |l|=1 fixed sin2β = 0.722 0.040 (stat) 0.023 (sys) when left free: |λ|=0.950 ± 0.031 (stat.) ± 0.013 S A Fitting function: Miss-tagging probability, resolution function: from self-tagged events B→D*ln, Dp, … BaBar, decay modes used: BaBar:
CKM Matrix – sin2f1 signal region yield 227M BB M.Bruinsma ICHEP’04 274M BB T. Higuchi ICHEP’04 BABAR J/ψ KL signal J/ψ X background Non-J/ψ background to isolate B→fCP decays from bckg. B→J/y KL B→J/y Ks Nsig=4370 Nsig=2788 Nsig=4150 Nsig=2722 B. Golob, University of Ljubljana 4 Seas Conference 2004, Istanbul
CKM Matrix – sin2f1 backup slide from b→sss S= 0.06 ± 0.33 ± 0.09 2.2s away from ccs 274M BB, ICHEP’04 penguin contribution ~ VcbVcs*=Al2 another penguin contribution ~ VubVus*=Al4(r-ih) S~sin2f1, theor. clean “sin2f1”= -0.96 0.51 152M BB, PRL91,261602(2003)
CKM Matrix – sin2f1 backup slide 227M BB, ICHEP’04 2.7s away from ccs 2.4s away from ccs S= 0.50 ± 0.25 ± 0.06 fKs average: 0.34±0.21 h’Ks average: 0.41±0.11 conservative upper bound: |SyKs-Sh’KS| <0.2 Grossman et al. Sh’KSorSfKS at present valuewould be sign of NP
CKM Matrix – f2 backup slide d d d b b b u u p+ u W+ u B0 p- d d u,c,t T ~ Vub*Vud ~ l3 S=sin2f2 A=0 W+ p0 p+ u u W+ B0 B0 d p- d p0 d d Tc ~ Vub*Vud P ~ Vtb*Vtd ~ l3 M+-= -Te-if2 + PeidP M+0= 1/√2(TceidC + T)e-if2 M00= 1/√2(TceidC e-if2 + PeidP) S = √(1-A2)sin2f2eff A ~ sindP Ispospin relations for B→pp f2 from B→pp BaBar
CKM Matrix – f2 backup slide 122M BB, Moriond QCD’04 Slong=-0.19±0.33±0.11 Along= 0.23±0.24±0.14 89M BB, PRL91(2003),171802 Br(B+→r+r0)=(22.5±5.6±5.8)x10-6 227M BB,M.A.Giorgi,ICHEP’04 Br(B0→r0r0) < 1.1x10-6 @90% CL B→rr from BaBar r+r- could be mixed CP state, but observed to be almost pure CP=+1 f2 from B→rr BaBar B→(rp)0 from Ba/lle r+p- not CP eigenstate, 4 amplitudes considered:
CKM Matrix – f2 backup slide G(B0→r+p-)+ G(B0→r-p+) G(B0→r-p+)+ G(B0→r+p-) Decay time distribution: indirect CPV parameter (f2) direct CPV parameter strong phase diff. between amplitudes asymmetry between direct CPV asymmteries Belle: selected bands BaBar: assume 3p dominated by r+,-,0 and fit Dalitz plot
CKM Matrix – f2 backup slide M.A.Giorgi,ICHEP’04
CKM Matrix – direct CPV backup slide 274M BB,Y.Sakai,ICHEP’04 B-→K-p0 B→K±p0 B+→K+p0 ACP= 0.04 ± 0.05 ± 0.02 c.f. inB→K+p- ACP= -0.101±0.025±0.005 2.4s diff. d p0 _ d ACP= 0.06 ± 0.06 ± 0.01 B- b K- BaBar,M.Chrintinziani,ICHEP’04 u u Large EW penguin?
CKM Matrix – direct CPV backup slide s K- u W- W- b s b K- u B0 u p+ d u B0 d d p+ d P ~ Vtb*Vts ~ Al2 T ~ Vub*Vus ~ Al4 u,c,t Contributions to B0→K-p+
CKM Matrix – f3 backup slide Basic idea: use B-→K-D0 andB-→K-D0with D0,D0→f interference ↔ f3 u b s D0 K- c u W- W- B- b c s u K- B- D0 u u d Tc ~ Vub*Vcs ~ Al3 (r+ih) ~ eif3 T ~ Vcb*Vus ~ Al3 Gronau,London,Wyler, 1991: B- → K-D0CP Atwood,Dunietz,Soni, 2001: B- → K-D0(*)[K+p-] Belle;Giri,Zupan et al., 2003: B- → K-D0(*)[Ksp+p-] Dalitz plot Sensitivity depends on or any other common 3-body decay; Dalitz density depends on f3
CKM Matrix – f3 backup slide Belle,152M BB A.Bozek,ICHEP’04 B+ D0K+ B- D0K- M2(Ksp-) M2(Ksp-) M2(Ksp+) M2(Ksp+) Belle: Use continuum D0 from D*– D0π–, D0 Ksπ+π–decay to model Dalitz plot density. B± D0 K± D0 Ksπ+π– B± D0 p± miss-id DE Mbc Visible asymmetry Fit with f3,d,rB free 26o <f3 <126o@ 95% C.L. rB = 0.26 ±0.110.15± 0.03 ± 0.04
CKM Matrix – f3 backup slide 20% 74% 97% rB BaBar,211M BB G.Cavoto,ICHEP’04 Belle,152M BB A.Bozek,ICHEP’04 f3 rB 90% 68% f3
CKM Matrix – |Vub| backup slide q2 Mx2 used in measurement (q2cut,MXcut) 8 GeV2, 1.7 GeV DVub 6%-9% only q2cut 11.6 GeV2 DVub 12%-15% C.W.Bauer et al.,hep-ph/0111387 large non-perturbative corr. (large th. uncertainty) MX only Babar-CONF-04/11,ICHEP’04 |Vub|= (4.77± 0.28 ± 0.28 ± 0.690.39)x10-3 Mx-q2 |Vub|= (4.92± 0.39 ± 0.36 ± 0.46)x10-3
CKM Matrix – |Vub| backup slide Mx-q2 |Vub|= (4.92± 0.39 ± 0.36 ± 0.46)x10-3 BaBar (stat.) (syst.) (th.) Belle |Vub|= (5.54± 0.42 ± 0.50 ± 0.55)x10-3 BaBar syst.: largest from detector (tracking, ID) and b→cln modeling Belle syst.: MC statistics
35±7 events M=3872.0±0.8 MeV G<2.3MeV (90%) X(3872) backup slide BaBar M(J/Yp+p-)
X(3872) hc” hc’ cc1’ y2 hc2 y3 M too low and G too small angular dist’n rules out 1+- G(gJ/y) way too small G(gcc1) too small; (PRL 93, 2003) pp hc should dominate ppJ/y G( gcc2 & DD) too small - Isospin violating decays to J/Yp+p- ccuu=1/√2 cc [1/√2 (uu+dd)+1/√2 (uu-dd)]=1/√2(|I=0>+|I=1>) backup slide C(J/y)=-1,C(w)=-1 → C(X)=+1 Since p is not C eigenstate, decayX→J/y pp is probably X→J/y r (as indicated by m(pp)) I(r)=1, I(w)=0, I(J/y)=0 → X decays break isospin symmetry
DsJ backup slide Belle, 87fb-1,PRL92,012002(2004) M(Ds*p0)-M(Ds*) M(Dsp0)-M(Ds) helicity angle: Feynman diagrams for B0→DsJ+K-