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Experimental review of CKM sides at B factories

Experimental review of CKM sides at B factories. A. Oyanguren (IFIC, UV-CSIC) (BaBar Collaboration). DISCRETE 2008. V td. V ub. V cb. Introduction & outline. The Cabibbo-Kobayashi-Maskawa matrix:. V ud V us V ub V cd V cs V cb V td V ts V tb. V CKM =.

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Experimental review of CKM sides at B factories

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  1. Experimental review of CKM sides at B factories A. Oyanguren (IFIC, UV-CSIC) (BaBar Collaboration) DISCRETE 2008 Vtd Vub Vcb

  2. Introduction & outline The Cabibbo-Kobayashi-Maskawa matrix: VudVusVub VcdVcsVcb VtdVtsVtb VCKM= VudVub* + VcdVcb* + VtdVtb* = 0  From Bd and Bs mixing [@ hadron colliders (md/ ms)]  From exclusive sl decays: |Vcb|: BD*l, BDl; |Vub|: Bl, Bl B(‘)l, Bl… A ~|Vtd/Vts|  From radiative decays (bd/bs) ~|Vub/Vcb| From inclusive BXcl (|Vcb|) and BXul (|Vub|) decays (1,0) (0,0) 1 2 DISCRETE 2008 A. Oyanguren

  3. B-Factories  1200 fb-1recorded ! Analysis techniques: - - Hadronic or Semileptonic Tag K+ D0 Untagged (High efficiency) (High purity) lepton D0 Signal side Signal side lepton lepton B0 B0 B0 - B0 B0 B0 D*    +  + (4S) (4S) X X X (4S) Tag side Tag side 3 DISCRETE 2008 A. Oyanguren

  4. |Vcb| from exclusive sl decays From B D   (BR ~2% , suppressed at high q2) From B D*   (BR ~ 5%) Vcb q2 Kinematic function Form factor (shape & normalization) Theory: G(1)*=1.074  0.018  0.016 B  DD2 F(1)*=0.921  0.013  0.020 B D* D*2, R1(1), R2(1) Measuring the decay rate and ff shape  |Vcb| * M.Okamoto et al NPPS 140, 461(2005)) * C. Bernard et al arXiv:0808.2519 [hep-lat] 4 DISCRETE 2008 A. Oyanguren

  5. |Vcb| from BD • Select the lepton, • reconstruct the D0 into several channels  Reconstruct the other B into hadrons (Btag)  Reconstruct the missing mass: m2miss = (p(4s)– pBtag-pD-pl)2 m2miss = 0.04 GeV2  Fit the signal yield into 10 w bins (ML fit) 417fb-1 2 = 1.20 0.09  0.04  2 fit to extract D2 and G(1)|Vcb| G(1) |Vcb| = (43.0 1.9 0.4) 10-3 B (B0D+-)= (2.170.06 0.07)% arXiv:0807.4978 5 DISCRETE 2008 A. Oyanguren

  6. |Vcb| from BD* • Reconstruct the semileptonic decay • D0K, K3 + soft  (to make D*) • + lepton • The decay rate depends • on w, , V ,  • Constraint pB  pinclusive = pall–D*  Define the angle between the B and the D* candidate  4D 2 fit to extract D*2, R1, R2 and F(1)|Vcb| w = 0.025 cosv= 0.052  Fit the signal yield 140 fb-1 = 6.47 cos=0.047 preliminary F(1) |Vcb| = (34.4 0.2 1.0) 10-3 R1= 1.495 0.050  0.062 2 = 1.293 0.045  0.029 R2= 0.844 0.034  0.019 B (B0D*+-) = (4.420.03 0.25)% DISCRETE 2008

  7. Global fit to BD and BD* 207fb-1 • Reconstruct D0 and D+ candidates • (D0K-+, D+K-++) B(B-D*0-)= (5.370.02 0.21)% D*2 = 1.21 0.02  0.07 • Use p*, p*D and cosB-D to separate • BD and BD* decays F(1) |Vcb| = (35.7 0.2 1.2) 10-3 B (B-D0-)= (2.360.03 0.12)% • 3D 2 fit to the yields to extract the • form factor slopes, D and D* and BD • and BD* BRs (R1 and R2 fixed). D2 = 1.22 0.04  0.07 G1) |Vcb| = (43.8 0.8 2.3) 10-3 D preliminary D* 1 1.5 2 1.5 2 -2 -1 0 1 arXiv:0809.0828 7 DISCRETE 2008 A. Oyanguren

  8. |Vcb| from exclusive sl decays G(1)|Vcb| = (42.4  1.56) x 10-3 2/dof =1.2/8 usingG(1) =1.074  0.024 |Vcb| = (39.5  1.5exp 0.9latt) x 10-3 Exp: - waiting Belle update - systematics  tracking eff, radiative corrections, D** F(1)|Vcb| = (35.41  0.52) x 10-3 2/dof =39/21 using F(1) =0.921  0.024 |Vcb| = (38.4  0.6exp  0.9latt) x 10-3 - systematics  tracking eff, D** 8

  9.  Fully reconstructed analyses BD**l HQET PRD77,091503(2008) 605 fb-1 D* ? D** D Ground states Broad states Narrow states • B(B0Xc) > B(B0D)+ B(B0D*)+ B(B0D**) [10.1  0.4]% + [5.16  0.11]% + [1-2]% > [2.17  0.12]% B0D*0+- B-D*+-- 417 fb-1 B-D+-- B0D0+-  Belle does not see the D1’, BaBar does. arXiv:0808.0528 Theory predicts B(D1*,D2*) >> B(D*0,D1’), Experiments see B(D1*,D2*) <~ B(D0*,D1’) 9

  10. |Vcb| from inclusive sl decays Operator Product Expansion (OPE): x = Vcb f(parametersrelatedwithbquark propertiesinsidethehadron) kineticenergy, spin... Some inclusive observablesO  depend on the same parameters BXc : theleptonenergy, themassdistribution, (Forinstance: BXs : thephotonspectrum) Measurement of moments:  10 DISCRETE 2008 A. Oyanguren

  11. MXcand El moments • One B fully reconstructed into hadrons (Btag) • Oneleptonfromtheother B (signal) •  measure E (electrons) • Rest of particles  measure mx • Event by event calibration • Unfolded with SVD algorithm • < Een> measured as function of p*e cut • (from 0.4 to 2. GeV/c) • < Mxn> measured as function of p*l cut • (from 0.8 to 1.9 GeV/c) PRD 75, 032001(2007) 210fb-1 140fb-1 e+ arXiv:0707.2670 • < Mxn> for n=1,2,3,4,5,6 • < Een> for n=0,1,2,3,4 11 DISCRETE 2008 A. Oyanguren

  12. g W+ S b t • Select high energy photons (E*> 1.4 GeV) • Off-peak subtraction, • veto to photons from 0 and  • Unfolded with SVD algorithm • < En> measured as function of • Ecut (from 1.7 to 2.1 GeV) 605fb-1 • < En> for n=1,2 PRD 78, 032016(2008) 12 DISCRETE 2008 A. Oyanguren

  13. |Vcb| from inclusive sl decays  Using 27 moments from BaBar, 25 moments from Belle and 12 momentsfromotherexperiments(http://www.slac.stanford.edu/xorg/hfag/semi/ichep08/gbl_fits/kinetic/) |Vcb| =(41.67  0.43fit 0.08 B  0.58th) x 10-3 mb =(4.601  0.034) GeV 2 =(0.440  0.040) GeV2 (Exclusive (BD*): |Vcb| = (38.4  0.6exp  0.9latt) x 10-3 |Vcb|incl - |Vcb|excl : 2.5 13 DISCRETE 2008 A. Oyanguren

  14. |Vub| from exclusive sl decays Analysis methods:  Untagged (high stat., most precise)  Tagged (hadron or semileptonic) (BR ~ 0.01% + large bc bkg) p, h, h’, r, w •  reconstruction from full event • (p = pbeams - pi)  Fit E = EB – s /2 and mES = s/4-|p*B|2 to extract the signal yield 206fb-1 • q2= (pB - p )2 in 12 bins  Form factor fit B (B0-)= (1.460.07 0.08)x10-4 PRL 98, 091801(2007) 14 DISCRETE 2008

  15. |Vub| from exclusive sl decays Tagged B pB (sl tag) B (hadronic tag) pD(*)l pl  Reconstruct one B into hadrons (Btag) • Select the lepton from the other B • One B decaying into B D(*) (Btag) • select the  ( rec.  or  into pions) • Other lepton (-q) from the other B  Reconstruct the missing mass: m2miss = (p(4s)– pBtag-p-pl)2 • Define the systems Y=D(*) and X= • Fit to cos2B in 3 q2 bins • Extract yields in 3 q2 bins 348fb-1 B0- B+0 605fb-1 signal signal 0805.2408 [hep-ex] B (B0-)= (1.120.18 0.05)x10-4 B (B0-)= (1.540.17 0.09)x10-4 B (B+0)= (0.660.12 0.03)x10-4 15 DISCRETE 2008 A. Oyanguren

  16. |Vub| from exclusive sl decays Form factor necessary to extract |Vub| theory Models depend on q2 region: (Untagged analysis can measure the form factor from data) B (B0-)= (1.340.06 0.05)x10-4 PRL 98, 091801(2007) 16 DISCRETE 2008 A. Oyanguren

  17. |Vub| from exclusive sl decays B  (,,’,)  Checktheoreticalcalculations Composition of BXu 348fb-1 605fb-1 signal hadron tag sl tag: 0805.2408 [hep-ex] 347fb-1 B (B0-)= (2.800.18 0.16)x10-4 untagged 0808.3524 [hep-ex] 17 DISCRETE 2008 A. Oyanguren

  18. |Vub| from inclusive sl decays 50 : 1 BX = BXc + BXu • Theoryneedslowmomentumcutstoextract|Vub| (OPE breaksdown in theShapeFunction (SF) region: • low mx2 and q2) • OPE parameteres (mb, 2 ) frommoments in BXc and BXs • Experimentsneedhighmomentum • cutstosuppressb  c bkg Experimental technique: Measure partial BR  Tagged (sl or hadronic) or untagged  Use kinematic variables to suppress as much as possible b  c (keeping reliable theoretical calculations): El, q2, mX and P+ = EX -|pX| 18 DISCRETE 2008 A. Oyanguren

  19. Tagged (hadrons or sl) • Select regions below charm threshold • Key: bkg subtraction (off-peak data, • endpoint, MC… ) • bc bkg constrained by data in the • low energy region • One B fully reconstructed • Access to all kinematics (mx, q2, P+) • for the signal side signal 81fb-1 signal PR73:012006,2006. signal 27fb-1 bc (MC) 347fb-1 bkg bkg ~40-60% acceptance 1.55 GeV 0.66 GeV signal 8 GeV2 arXiv:0708.3702 PRB601:28(2005) 81fb-1 signal 604fb-1 bkg Shmax=f(E, q2) = maximum mx squared (new Belle multivariate analysis  no hard cuts, 90% PS) PRL95:111801(2005)

  20. |Vub| from inclusive sl decays Tagged (hadrons or sl) • Relating the rate to bs to reduce • model dependence (LLR method)  Moments of the full mass spectrum  OPE fit to extract mb, 2 and . unfolded 220fb-1 80fb-1 B  Xc B  Xs  B  Xu mx cut =1.67 mb =(4.604  0.250) GeV arXiv:0801.2985 2 =(0.398  0.240) GeV2 PRL96:221801(2006) mx cut (GeV/c2) 20 20

  21. |Vub| from inclusive sl decays OPE based + SF ‣BLNP: HQE with systematic introduction of SF PRD71:073006 (2005) ‣BLL: phase space in mx-q2 with reduced SF PRD64:113004 (2001) ‣GGOU: kineticscheme JHEP 10(2007) 058 ‣LNP (LLR): b→s directly related to b→ uν JHEP 0510:084 ( PLB 486:86 ) No SF introduced (model non-perturbative QCD) ‣DGE: DressedGluonExponentiation JHEP 0601:097 (2006) ‣ADFR: Analyticcoupling PRD74:03400(4,5,6) (2006) Vub incl Vub excl More data, more SP + improvementsfromtheoryneeded |Vub|from =(3.44  0.16)10-3 21 DISCRETE 2008 A. Oyanguren

  22. |Vtd/Vts| from radiative decays  Exclusive b u,c,t d/s  - , / K* B- Inclusive (Sum of all channels) Formfactors u arXiv:0804.4770 • Select high energy photons B→ Xsg • veto to photons from 0 and  • remove bkg from continuum  Yield from E = EB – s /2 and mES = s/4-|p*B|2 0.6 < MXd/s < 1.0 GeV (error from fBsBBs / fBdBBd ) B→ Xdg NeedSuperB! 1st error exp., 2nd theo. 22 DISCRETE 2008 PRL101:111801,2008

  23. Summary The CKM matrix:  decays  Decays (0+0+) Vud/Vud ~ 0.03% Vus/Vus ~ 0.4% Vub/Vub ~ 8% Vcd/Vcd ~ 5% Vcs/Vcs ~ 11% Vcb/Vcb ~ 2% Needtheoryimprovements (excl . vs incl. ??) (Vtd/Vts)/(Vtd/Vts) ~ 3% Vtb/Vtb ~ 15% charm sl decays 23 DISCRETE 2008 A. Oyanguren

  24. Backup HFAG 24 DISCRETE 2008 A. Oyanguren

  25. Backup HFAG 25 DISCRETE 2008 A. Oyanguren

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