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Recent results on CP violation from the B factory experiments

Recent results on CP violation from the B factory experiments. SLAC Summer Institute July 27, 2011. J. Chauveau LPNHE Université Pierre et Marie Curie, Paris-VI. On behalf of the BABAR Collaboration. Context. Motivation for the B factories The BABAR Physics Book SLAC-R-504 (1998)

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Recent results on CP violation from the B factory experiments

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  1. Recentresults on CP violation from the B factoryexperiments SLAC Summer Institute July 27, 2011 J. Chauveau LPNHE Université Pierre et Marie Curie, Paris-VI On behalf of the BABAR Collaboration

  2. Context Motivation for the B factoriesThe BABAR Physics Book SLAC-R-504 (1998) • Primary goal: To test the Cabibbo-Kobayashi-Maskawa model for CP Violation ( KvsB) Overconstrain the Unitarity Triangle, the “UT” (sides, angles) • Does it close ? • Is there New Physics Beyond the Standard Model? (CKM not enough for A(baryon)) • Other goals What now ? J. Chauveau XXXIV SSI

  3. Outline • CP-violation (CPV) and the CKM model • The B factories • The angles of the UT (hadronic B decays) • b/f1 • g/f3 • The sides (semileptonic/leptonic) B decays • Rare hadronic/radiative B decays • Search for CPV in charm and tdecays • Outlook B charmonium K0 B(D or D) K B ffK J. Chauveau XXXIV SSI

  4. CP mixing decay CP violation in (B) meson decay At least 2 amplitudes for CP violation to occur. 3 types of CP violation: • Direct charged and neutral B strong phases • In mixingneutral suppressed • In the interferenceneutral golden modes betweenmixing and decay + others. • One or several types. J. Chauveau XXXIV SSI

  5. CKM: the matrix and the triangle W- uj Vij /2 /3 /1 di Wolfenstein parameterization J. Chauveau XXXIV SSI

  6. CKM matrix and the UT CKMfitter: http://ckmfitter.in2p3.fr , UTfit: http://www.utfit.org/UTfit/ J.Chauveau CPV in B and CKM

  7. B factories SLAC PEP-II BELLE KEK-B 1031 fb-1 770 M BB 531 fb-1 470 M BB J. Chauveau XXXIV SSI

  8. ON Υ(4S) peak √s = 10.58 GeV OFF peak √s = 10.54 GeV PEP-II and BABAR Asymmetricenergies, Y(4S) boosted, bg=0.56 J. Chauveau XXXIV SSI

  9. BABAR Collab. B. Aubert et al., Nucl.Instrum.Meth.A479:1-116,2002 J. Chauveau XXXIV SSI

  10. J. Chauveau XXXIV SSI

  11. The angles /2 /3 /1 J. Chauveau XXXIV SSI

  12. Time dependent CP Asymmetries(the angle b/f1) b c b d(s) J/ψ KS(Ф) c d(s) t s B(s)0 B(s)0 s For B decaying to fCP (CP eigenstate) . c KS(Ф) J/ψ d(s) d(s) d(s) c t b V*td(s) Im lf=hCP sin 2b CP mixing decay J. Chauveau XXXIV SSI

  13. B charmonium K0 770 M BB H. Sahooat FPCP-2011 New Belle Result on full dataset 12681  114 10041  154 1981  46 943  33 # events J. Chauveau XXXIV SSI

  14. b (c cbar) s S=0.666 ± 0.031 ± 0.013 C=0.016 ± 0.023 ± 0.018 Phys.Rev.D79:072009,2009 S=0.668 ± 0.023 ± 0.013 C=0.007 ± 0.021 ± 0.014 PRELIMINARY (Moriond EW ) 465 MBB 772 MBB J/ KS J/ KL J. Chauveau XXXIV SSI

  15. The angle b (bccs) In SM, expect, S=sin2b, C=0 sin2b= 0.678  0.020 b=(21.4  0.8) 0 J. Chauveau XXXIV SSI

  16. The angle b (bs penguin) loop • b  ssssameweak phase as b  ccs • onlyapproximate: depends on hadronic • parameters • oftenincreasingbeff • oftensmall. J. Chauveau XXXIV SSI

  17. The angle a/f2 • Most sensitive results are not recent, not describedhere. In a nutshell: • TDCP more complexbecause of the Penguin pollution. • Solvable in 2-body (pp) or quasi-2-body (rr)using isospin (Gronau-London [GL] method) • Dalitz analyses of the rpchannelsalso sensitive • The rrchannelusing GL is the most sensitive (Penguin amplitude small and wellmeasurable) d π- d V*td Vub u π+ u b d u b u B0 t π+ B0 V*ub π- d d d b d t J. Chauveau XXXIV SSI

  18. The angle g/f3 • B D(*)K(*),D or D* D • sameD final state,henceb  uW and b cWinterfere (arg[Vub]=-g). • Pure Treeprocesses! • Large uncertaintiesbecause disparate magnitudes (color suppression) • Works for charged (and neutral) B’s. s b u K+ u D0 c Vub b c B+ B+ D0 s u u K+ u u J. Chauveau XXXIV SSI

  19. f3/gmethods • Gronau London Wyler: D  CP eigenstates • R±CP= 1 + rB2 ±2rBcos(dB)cos(φ3), • A±CP= ±2rBsin(dB)sin(φ3) / R±CP GiriGrossmanSofferZupan: Dalitz 3-body D decaysnew results x+ = rB cos(dB+φ3 ) y+ = rB sin(dB+φ3 ) x− = rB cos(dB−φ3 ) y− = rB sin( dB−φ3) Benefitsfromcharmmeasurements (CLEO-c) • Atwood DunietzSoni: DCSD(bc) + CA(bu) new results • RADS = rB2 + rD2 + 2 rBrD cos(dB +dD) cos(φ3), • AADS = 2 rBrD sin(dB +dD) sin(φ3) / RADS rB, dB, dD, f3 J. Chauveau XXXIV SSI

  20. The angle g/f3 (GGSZ) • Assuming no CPV in D decays and neglecting D mixing, s- s+ • Measure Dalitz plot from D*+Dp+ in the same data samplewith • Dalitz plot model to describe the dD(s+,s-) phase motion brings dominant systematics s+ s- PRL 105, 121801 (2010) Phys. Rev. D 81, 112002 (2010) HFAG-2010 J. Chauveau XXXIV SSI

  21. New GGSZ result Giri, Grossman, Soffer, Zupan, PRD 68 05418 (2003) A. Bondar, Y Poluetkov, PRD70, 072003 (2004) J. Dalseno (Belle) EPS 2011 • to remove model systematics, use optimal binning in the Dalitz plot (DP) • Uses the CLEO (eventually BES-III) quantum correlation in e+e-  DD at Psi ‘’ (s+) (s-) • DP systematicsreduced by one half • losestatisticalprecision, • irrelevant for 10 ab-1samples Preliminary J. Chauveau XXXIV SSI

  22. The angle g/f3 g = (71 +21 )0 -25 • The only angle withexperimental • precisionworsethan the fit. • Great expectations from LHCb. • Recall, pure treeprocesses. J. Chauveau XXXIV SSI

  23. nt l(t) n W- b q l u Vub W- b c or u VcborVub h/X u,d The sides J. Chauveau XXXIV SSI

  24. (Semi)leptonic B decays R. Kowalewskiat Beauty 2011 • |Vcb| (10-3) • Exclusive 38.9  1.1 • Inclusive 41.9  0.7 • Average 41.0  1.3 scale factor 2.2 • in CKMfitter: 40.89 0.38 0.59 • |Vub| (10-3) • Exclusive 3.25  0.12  0.28 • Inclusive 4.25  0.15  0.20 • Average 3.97  0.43 scale factor 2.0 • In CKMfitter: 3.92  0.09  0.45 • BR (B  tnt) (10-6) In CKMfitter: 168  31 J. Chauveau XXXIV SSI

  25. Vub, Vub/Vcb, status • Marginal agreement betweeninclusive and exclusive measurementsboth for Vub and Vcb • VubfromtnexceedsVubfromsemileptonics J. Chauveau -- Capri Workshop

  26. Whereis the new physics? Global CKMfits Roadmap • Pure treeprocesses to determine the SM parameters. g! • loops (mixing, FCNC (penguins)) to determinesameparameters and look if they are different. CKMfitter: http://ckmfitter.in2p3.fr , UTfit: http://www.utfit.org/UTfit/ CKMfitter Input: |Vud|, |Vus|, |Vcb|, |Vub|, BR(B  tn) Dmd, Dms, eK, sin2b, a, g. CL=95,45% SM p-value 3.3% (or 2.1s) arXiv:1106.4041v1 [hep-ph] • acceptable consistency • there are tensions • Look for New Physics • in quantum fluctuation processes • akaloops J. Chauveau XXXIV SSI

  27. Loops… • Charmlesshadronic B decays (gluonic Penguins) • 3-body e.g. B  PPP • quasi 2-body like B  VV, polarization puzzle • final states witheven more multiplicity An exampleisBffK • Rare radiative decays (EW Penguins) J. Chauveau XXXIV SSI

  28. B  f f K (1) • SM physics in the twodiagrams, canbeconsidered a single weak • amplitude, hence no CP-asymmetrypredicted by the SM. • A ‘New Physics’ diagrammay carry a non trivial phase, modelspredict • ACPas high as 40% [M. Hazumi PLB583, 285 (2004)] • This analysis: • measure the B+ and B0branching fractions below and under the hc • measure the corresponding CP-asymmetries • understand the partial wavesatplay J. Chauveau XXXIV SSI

  29. J. Chauveau XXXIV SSI

  30. B  f f K (2) 1 • Signal: B to five kaons • backgrounds • peakingfrom B decays • continuum Zones in (mf1, mf2) plane 4 3 2 5 multivariate techniques to fight the contimuum background. Here: a Fisher discriminant Signal continuum J. Chauveau XXXIV SSI

  31. B  f f K (3) PRD84, 012001 (2011) ACP(mff <2.85 GeV) = -0.10  0.08  0.02 ACP(mff in [2.94, 3.02] GeV) = hc cc ACP ~0 consistent with SM J. Chauveau XXXIV SSI

  32. Search for CPV in t/charm • Charm • D mixingestablished • Is CPV next? • In mixing? • In decay? • Hugestatistics and favorable S/B in decays • 2-body • 3-body • Triple productasymmetries • Rare decays • Taus Recentmeasurements by Belle and BABAR of ACP in tKsp nt Nothingsignificantyet J. Chauveau XXXIV SSI

  33. The Bs • Hadron collidersexperiments have the lead. • Bsmixing • Asl • BsJ/  • bccs similar to Bd J/Ks, but B  VV • hence spin complexity. • BsJ/ f0 more tractable. • Belle (and BABAR) ranabove the Y(4S) • fs: Bs fraction in continuum (fromsemileptonicdecaysat BABAR), • BsJ/ f0 (seenat Belle) J. Chauveau XXXIV SSI

  34. Summary and outlook • The wealth of the B factoryresultswerekey to establish the CKM model as the dominant mechanism of all observed CP-violation. • CP and CKM relatedresults are only one part of the B factoryharvest. • e+e- clean environmentenables to performquiteinvolved analyses. • There are stillmany analyses in progress • BABAR and BELLE collaborate to produce the PBF book to document ‘legacy’ analyses, • LTDA effort developped to keep BABAR dataset usable in the (far) future. • Nowis the time for bphysicsat hadron colliders. • What ‘New Physics’ at the energyfrontier (if any…), or above? • What impact on the flavorproblem? • Currentphenomenologyimplies a non generic NP flavorsector. • New e+e- colliders are approved to collectdatasets 50-100 bigger. J. Chauveau XXXIV SSI

  35. Backup slides J. Chauveau XXXIV SSI

  36. BABAR TopCite100+ References (May 2010) • The BABAR Physics Book SLAC-R-504 (1998) • BABAR detector: Nucl.Instrum.Meth.A479:1-116,2002 • HFAG: http://www.slac.stanford.edu/xorg/hfag/ • CPV in B decay: • Discovery Phys.Rev.Lett.87:091801,2001 (BABAR), - 091802 - (Belle) • Long paper Phys.Rev.D66:032003,2002. • Charmless 2-body: Phys.Rev.Lett.89:281802,2002. • Ds0*(2317)+: Phys.Rev.Lett.90:242001,2003. • Polarization puzzle in B→VV: Phys.Rev.Lett.91:171802,2003. • B ---> X(s) l+ l- :Phys.Rev.Lett.93:081802,2004. • B ---> X(c) l nu and |V(cb)|: Phys.Rev.Lett.93:011803,2004. • B- ---> X(3872) K- : Phys.Rev.D71:071103,2005. • Direct CP in B0 ---> K+ pi-: Phys.Rev.Lett.93:131801,2004. • Ambiguity-free measurement of cos 2beta: Phys.Rev.D71:032005,2005. • X(4260): Phys.Rev.Lett.95:142001,2005. • t→e,m+g:Phys.Rev.Lett.96:041801,2006, Phys.Rev.Lett.95:041802,2005. • D mixing: Phys.Rev.Lett.98:211802,2007. J. Chauveau XXXIV SSI

  37. http://www-public.slac.stanford.edu/babar/Poster/slac_nobel_poster_2008.pdfhttp://www-public.slac.stanford.edu/babar/Poster/slac_nobel_poster_2008.pdf J. Chauveau XXXIV SSI

  38. Amplitude structure in the SM T P EWP Cabibbo and color suppression l4 l2 Accs ~ Vcb Vcs* Tccs + Vub Vus* Ps Asss ~ Vcb Vcs* P + Vub Vus* P Accd ~ Vtb Vtd* P + Vcb Vcd* Tccd Auud ~ Vtb Vtd* P + Vub Vud* Tuud (Tcus + Tucs) common D decay modes Charmonium KS,L b FKS b D+D- b+f p+p- aeff GOLDEN eff l3 DK g J.Chauveau CPV in B and CKM

  39. b → qq-bar s (penguin) s • Loop diagrams with same weak phase as ccbar s in SM • new physics in loops ? • New results available, in particular from amplitude analyses J.Chauveau CPV in B and CKM

  40. (flavor eigenstates) lifetime, mixing analyses (CP eigenstates) CP analysis Experimental Technique Exclusive B Meson Reconstruction B-Flavor Tagging J. Chauveau XXXIV SSI

  41. The angle gamma (ADS) Phys. Rev. D 84, 012002 (2011) J. Chauveau XXXIV SSI

  42. 3/gresults (GGSZ) PRL 105, 121801 (2010) D Ksp+p- D Ks K+ K- DK D*K D*D0p0 s- D*K D*D0g DK* mES DE s- s+ mES DE s- s+ J. Chauveau -- Capri Workshop

  43. 23 23 23 Phys. Rev. D 81, 112002 (2010) GGSZ PRL 105, 121801 (2010) J. Chauveau -- Capri Workshop

  44. Summary on angles • CP violation established • the angles alone bring a significant constraint on the UT apex • g/f3: more precision needed to bring a constraint J. Chauveau XXXIV SSI

  45. CP conserving w/o tn sl and tn separately Vub averaged Summary on sides J. Chauveau -- Capri Workshop

  46. n q l b W- c or u VcborVub h/X u,d nt l(t) b W u Vub R. Kowalewski Beauty 11 Methods • Semileptonic inclusive and exclusive B decays • Wellestablished analyses • Can use recoilsamples (hadronic or semileptonic tags) • Inclusive: bq ln + QCD corrections+OPE (as, L/mb) also relevant for b s g • Exclusive: form factor(s) describing B  ln hadron – LQCD • Systematic trend where the inclusive results are higherthan exclusive ones. • Purelyleptonic B decays (B tn) • Theory more straightforward, still LQCD for fB • Underconstrainedevents  taggedsamples • Very hard measurements J. Chauveau -- Capri Workshop

  47. B Kpp0 J. Chauveau XXXIV SSI

  48. B Kpp0 J. Chauveau XXXIV SSI

  49. J. Chauveau XXXIV SSI

  50. Rare radiative decays J. Chauveau XXXIV SSI

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