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Beauty and charm results from B factories

Beauty and charm results from B factories. B oštjan Golob University of Ljubljana , Jožef Stefan Institute & Belle Collaboration. Helmholtz International Summer School “Heavy Quark Physics” Bogoliubov Laboratory of Theoretical Physics, Dubna, Russia, August 11-21, 2008. “Jožef Stefan”

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Beauty and charm results from B factories

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  1. Beauty and charm results from B factories Boštjan Golob University of Ljubljana, Jožef Stefan Institute & Belle Collaboration Helmholtz International Summer School “Heavy Quark Physics” Bogoliubov Laboratory of Theoretical Physics,Dubna, Russia, August 11-21, 2008 “Jožef Stefan” Institute University of Ljubljana JINR

  2. Lecture 1 • Beauty • Introduction • B Oscillations • (Mostly) rare B decays • leptonic • semileptonic • b →sg • b →sll • Lecture 2 • Charm and others • 4. D0 mixing and CPV • decays to CP states • WS decays • t-dependent Dalitz • 5. Ds leptonic decays • 6. Spectroscopy • exotic states Outline exp. results with some comments on phenomenology It is a curious fact that people are never so trivial as when they take themselves seriously. O. Wilde (1854 - 1900) Part of B-factories lectures with A.J. Bevan; division by topics, not by experiments

  3. Introduction Experiments very diverse exp. conditions We all live with the objective of being happy; our lives are all different and yet the same. Anne Frank (1929 -1945) on resonance production e+e-→ U(4S) → B0B0, B+B- s(BB)  1.1 nb (~0.9x109 BB pairs) continuum production s(c c)  1.3 nb (~109 XcYc pairs) c g* • e+e-→ y(3770) → D0D0, D+D- • (coherent C=-1 state); • ~800 pb-1 of data • available at y(3770); • 2.8x106 D0D0 3.5 fb-1 on tape s(D0; pt>5.5 GeV,|y|<1)≈ ≈13 mb 50x109 D0’s c

  4. q2 q1 diagonal elem.: P0 P0 (including decays) non-diagonal elem.: P0 P0 q2 q1 B oscillations P0 P0 Time evolution (also lectures by U. Nierste, A. Pivovarov) flavour states ≠ Heff eigenstates: (defined flavour) (defined m1,2 and G1,2) P0 = K0, Bd0, Bs0 and D0 eigenvalues: more

  5. D. Kirkby, Y. Nir, CPV in Meson Decays, in RPP B oscillations Time evolution P1,2 evolve in time according to m1,2 and G1,2: |P0(t)>, |P0(t)> decay rates: for easier notation: Gt → t U(4S) →B0B0: B meson pair in quantum coherent state; before 1st B decay: B0B0 1st B decay: tag B0/B0; mixing clock start, t →Dt Decay time distribution of experimentally accessible states P0, P0 sensitive to mixing parameters x and y, depending on final state more

  6. B oscillations Time evolution probab. to observe an initially produced X0 as X0 after time t probab. to observe an initially produced X0 as X0 after time t ~ Bs0 ~ D0 more difficult to observe oscillations within t visually unobservable deviation from pure exponential

  7. Btag B0 or B0 determined B0(B0) B oscillations signal Method similar to CPV, reconstruct flavor specific final states signal m+ m- fully reconstruct decay to flavor specificfinal state J/y p- Bsig K+ K*0 tag flavor of other B from charges of typical decay products l- U(4S) K- Dt=Dz/bgc determine time between decays

  8. Belle, PRD71, 072003 (2005), 140 fb-1 B oscillations DE signal region Method reconstructed flavour specific decays measure Dt distribution Method Dt distribution Af=0, |y|<<1 w: wrong tag probability (reduces ampl. of oscillations) R(Dt): resolution function - intrinsic detector resolution on position of both B vertices - smearing due to non-primary tracks - smearing due to B meson CMS momentum saver(Dt)=1.43 ps more more

  9. Belle, PRD71, 072003 (2005), 140 fb-1 B oscillations Results flavour asymmetry Dmd=(0.511±0.005±0.006) ps-1 largest syst.: D** bkg. Dmd=(0.507±0.005) ps-1 x=DmdtBd= 0.776±0.008 HFAG, http://www.slac.stanford.edu/xorg/hfag/

  10. Vjb* Vid Vjd Vib* b d W+ b d B0 B0 u, c, t u, c, t u, c, t u, c, t B0 W- W+ B0 W- d b b d B oscillations P0: any pseudo-scalar meson; specific example of Bd0 Phenomenology (see also lectures by U. Nierste) P0-P0 transition → box diagram at quark level if mi = mj  due to CKM unitarity: no mixing loop int., CKM unitarity  more considering CKM values and q masses: largest contribution from t quark

  11. B oscillations A.J. Buras et al., Nucl.Phys.B245, 369 (1984) Phenomenology calculate M12, G12 from box diagram; from that calculate Dm, DG must be calculated to determine Vij; theor. uncertainty (LQCD) q: d (Bd) or s (Bs); and Dms also measured... BBq: bag parameter, <Bq0|bgm(1-g5)q|Bq0> fBq: decay constant hB(‘): QCD corr. O(1) S0(xt): known kinematic function reduced theor. uncertainty in ratio x2 M. Okamoto, hep-lat/0510113

  12. CDF, PRL97, 242003 (2006) B oscillations A Bs amplitude method: instead of Dms fit A at different values of Dms; A=1  oscillations at this Dms value Dms=(17.77±0.10±0.07) ps-1 x=DmstBs= 25.5±0.6 Dms/Dmd uncertainties on (r2+h2): Dmd constraint ±13% Dmd±1% fBdBBd ±12% Dms/Dmd constraint ±6% Dms /Dmd ±1.5% x ±5%

  13. Q fP Leptonic B decays l+ (H+) P+ B → tn W+ G(B+→ t+n): G(B+→ m+n): G(B+→e+n)= 1:4x10-3:10-7 fP→ meas. VQq; H±; VQq n q Method fully reconstruct Btag in hadronic decays (K+p-p+p-p+); search for 1/3 tracks from Bsig→tn (e-); no additional energy in EM calorim. (from p0, g, ...); signal at EECL~0 EM calorim. B → tn candidate event

  14. Belle, PRL97, 251802 (2006), 414 fb-1 Belle, ICHEP08, 600 fb-1 Leptonic B decays Results largest syst. from signal and bkg. shape semileptonic tag added BaBar: hadronic decays for Btag; combined with semil. decays: bkg. Nsig=17 ± 5 3.5 s signif. (-2lnL0/Lmax) signal BaBar, PRD77, 011107 (2008), 346 fb-1 BaBar, PRD76, 052002 (2007), 346 fb-1 expected signal Br=3x10-3 HFAG, http://www.slac.stanford.edu/xorg/hfag/ more

  15. Leptonic B decays Phenomenology using fB=(216 ± 22) MeV, |Vub|=(3.9 ± 0.5)x10-3, tB  BrSM(B+→tn) = (1.25± 0.41)x10-4 new physics: to make predictions/measure |Vub| → fB (from LQCD) needed; validate LQCD in charm sector (better exp. precision) → to be addressed later; established method for decays with large Emiss; to be exploited at SuperB (B→Knn, dark matter) HPQCD, PRL95, 212001 (2005) u t b H+ B- n SuperB 50 ab-1 more

  16. l+ n q1 q3 M2 M1 q2 Semileptonic B decays W±, H± P →Pln q2 in G suppressed by ml2/mM12 negligible for e,m; not for t P →Vln 3 form f. for e,m; 4 for t HQS: relations among f.f.’s; can be tested; for suppressed f.f.’s only by t H± exchange modified SM Br’s for t; in P→ V only helicity=0 V possible measurement challenging due to multiple n’s; more more skip

  17. Semileptonic B decays D* e/p • B0→D*-t+nt • method: • D* reconstruction; • t→enn, pn • Bsig: D* and e/p • Btag: rest of event • control sample: • Bsig→D*p , check Btag reconstruction • signal sample: • requirements on Xmis, Evis • method: • excl. Btag reconstruction • t→enn, mnn • Bsig: D/D* and e/m • mmis2=pmis2 t Bsig Btag Belle, PRL99, 191807 (2007), 480 fb-1 n n Bsig→D*p MC data BaBar, PRL100, 021801 (2008), 209 fb-1 related to missing mass (>0 for several n); Evis < m(U(4S)) missing mass (>0 for several n);

  18. Semileptonic B decays Belle, PRL99, 191807 (2007), 480 fb-1 • B0→D*-t+nt • results • bkg. from B0→D*en (peaking) • t→rn Nsig=60 ±12 6.7 s signif. (-2lnL0/Lmax) main systematics: from signal and bkg shape (MC) Btag reconstr. eff. (control sample) BaBar, PRL100, 021801 (2008), 209 fb-1 D*-l+n D*-t+nt last uncertainty: normaliz. modes (Dln , D*ln) main systematics: from signal and bkg shape (MC) D** contrib. D-l+n D-t+nt

  19. M. Tanaka, Z.Phys.C67, 321 (1995) Semileptonic B decays • B →D(*)tnphenomenology • limits on H±; • inclusive B →Xctn predicted Br: • (2.30 ±0.25)% • sum of D*tn, Dtn: • (2.59 ±0.39)% Ba/lle average (assuming no correl. and 100% long. polariz.) A.F.Falk et al., PLB326, 145 (1994) G(B →D*long.tn) G(B →D*mn)|SM BaBar more

  20. b → sg H± b s • Motivation • FCNC process; • sensitive to NP in loop; • parton level: Eg≈ mb/2; • determ. of mb, Fermi motion → • needed for Vubdeterm. from • inclusive semil. B decays; • Difficulties • theory: • parameter extraction from • partial Br(Eg>Ecut) → • extrapolation needed; • experiment: • measure low Eg • huge bkg. X Y W± u, c, t b s g c± Vqb Vqs b s u, c, t g X Y g continuum p0 Your background and environment is with you for life. No question about that. signal more S. Connery (1930)

  21. on off b → sg • Inclusive measurement • (see also lectures by U. Heisch) • only g reconstructed; • bkg. treatment • subtract lumin. scaled off-data • from on-data (continuum bkg.); • veto p0, h → gg; • rest bkg. from MC (control samples); • timing info for EM calorim. clusters • (overlapping evts.: hadronic + Bhabha) • inclusive B→p0X, hX samples • reconstructed in data • (off- data subtraction) and MC; • 5%-10% correction to MC bkg. normaliz. on scaled off Belle, arXiv:0804.1580, 605 fb-1 subtracted 80% of remaining bkg. from p0, h → gg after vetoing p0, h → gg more

  22. Belle, arXiv:0804.1580,605 fb-1 b → sg consistent with 0 above B decay threshold • Inclusive measurement • Eg spectrum • Br(B →Xsg) • deconvolution of Eg • (Egmeas→ Egtrue; using • radiativedi-muonevts); • boost to B rest frame; • b →dg contrib. (4%); mb1S/2~2.3 GeV last uncertainty due to boost; largest system.: corr. factors in off-data subtraction; bkg. g’s from B (other than p0, h)

  23. BaBar, PRD72, 052004, 82 fb-1 b → sg • Seminclusive measurement • B reconstructed; • (see also lectures by B. Pecjak) • sum of exclusive decay modes • Xs: no S-wave states in B→Xsg • 22 final states K-(0)+(1-4)p • 10 K-(0)+h+(0-2)p • 6 3K-(0)+(0-1)p • g + Xs B • (better resol.) • bgk.: p0, h veto, NN from topological • variables for continuum; • not all final states reconstructed • →corr. for missing fraction • (from MC, checked with data in various • final state categories) peaking bkg.: missing final states reconstructed as one of signal decays; signal decays with some particles exchanged with other B 25% at low M(Xs) from KL at high M(Xs) from K+ 5p

  24. BaBar, PRD72, 052004, 82 fb-1 b → sg Seminclusive measurement fit in bins of M(Xs) Br(M(Xs)); Eg spectrum (Eg>1.9 GeV); moments of dG/dEg also determined; mb (and other QCD parameters) determined for use in b →uln; e.g. main systematics: from missing final states K*(892) more more details at HFAG, http://www.slac.stanford.edu/xorg/hfag/

  25. M. Misiak et al., PRL98, 022002 (2007) b → sg Phenomenology average of results: comparison with limits from B →tn: HFAG, winter 08, http://www.slac.stanford.edu/xorg/hfag/ 95% C.L. lower limit on m(H±), all tanb first error: stat.+syst. second error: Eg spectrum (extrapol.) m(H±)=300 GeV Belle, PRL97, 251802 (2006), 414 fb-1 For my part I know nothing with any certainty, but the sight of the stars makes me dream. V. van Gogh (1853 - 1890)

  26. b → sll Motivation (see also lectures by E. Lunghi) FCNC process; M expressed in terms C7,9,10; Wilson coeff.’s NP modifies C7,9,10 or/and adds new operators Wilson coeff.’s independent of final state (C7 same for b→sg and b→sll); |C7 |2 constrained by Br(B→Xsg); sign not known; b→sll: interference of amplitudes additional information (also sign) on C7,9,10 W± b s Vqb Vqs u, c, t g = perturbative (dependence on MW, mt, MNP) non-perturbative b s =VqbV*qs C7x g more

  27. b → sll exclusive B →K*ll qKdistrib.  fraction of long. polarized K* (FL); qldistrib.  lepton forward-backward asymmetry (AFB); prediction for AFB: q2=m2(l+l-) l+ ql K* B l- veto veto high q2 low q2 SM K C7 = -C7SM qK l+l- K* B C9 C10 = -C9SM C10SM C7 = -C7SM C9 C10 = -C9SM C10SM p q2

  28. BaBar, arXiv:0804.4412, 350 fb-1 high q2 low q2 b → sll Ns=27.2 ±6.3 • reconstruction • e+e-, m+m-; K* →Kp, Kp0, Ksp; • Mbc fit • combinatorial bkg.: e+m-; • misid. hadrons: h+m-; • peaking bkg.: D(→K*p)p • (mm sample only, • veto on m(K*p)); • signal fraction • qK fit • FL free parameter; • ql fit • AFB free parameter; Ns=36.6 ±9.6

  29. b → sll average over interval SM results FL; consistent with SM and -C7SM; AFB; -C9SM C10SM disfavored (>3 s); stronger constraints; C7 = -C7SM BaBar, arXiv:0804.4412, 350 fb-1 q2 Belle, PRL96, 251801 (2006), 357 fb-1 Belle, ICHEP08, 600 fb-1 SM C7 = -C7SM C9 C10 = -C9SM C10SM C7 = -C7SM C9 C10 = -C9SM C10SM more

  30. b → sll Belle PRD72, 092005 (2005), 140 fb-1 semi-inclusive similar as b →sg; e+e-, m+m-; K-/Ks+(0-4)p; ~30% missing modes; charmonium sample provides cross-check of bkg.; constraints on NP in Ci Br(B →Xsg), Br(B →Xsll), Br(K →pnn ) Br(Bs→mm), no Br(B →K*ll ) (large th. uncertainty) Nsig=68 ±14 5.4 s signif. (-2lnL0/Lmax) Belle PRD72, 092005 (2005), 140 fb-1 BaBar PRL93, 081802 (2004), 82 fb-1 dC10 dC9 J. Kamenik, arXiv:0805.2363 dC9 dC7

  31. B oscillations more D. Kirkby, Y. Nir, CPV in Meson Decays, in RPP Time evolution state initially produced as superposition (n.b.: a(0)/b(0) can be 0) will evolve in time as if interested in a(t), b(t): effective Hamiltonian and t-dependent Schrödinger eq.: eigenstates: (well defined m1,2 and G1,2) back

  32. diagonal elem.: P0 P0 (including decays) non-diagonal elem.: P0 P0 B oscillations more Time evolution eigenvalues: P1,2 evolve in time according to m1,2 and G1,2:

  33. B oscillations more Time evolution eigenvalues:

  34. B oscillations more Time evolution eigenvalues: back

  35. B oscillations more Time evolution taking into account we arrive at time evolution of P0, P0: back

  36. B oscillations more Time evolution decay rates: for CP conjugated states: Af → Af, Af→ Af

  37. B oscillations more CPV |p/q|=1, y<<1  (well fulfilled for Bd) |lf|≠1 |Af/Af|≠1 CPV in decay |q/p| ≠1 CPV in mixing I(lf) ≠ 0 CPV in interf. back

  38. Belle, PRD71, 072003 (2005), 140 fb-1 B oscillations more Method reconstructed flavour specific decays; D*ln =0 known meas. known meas. known meas. meas. total bkg D** bkg. back

  39. H. Kakuno et al., NIM A533, 516 (2004) B oscillations more Method tagging q=+(-)1 B0(B0) r: tag quality

  40. H. Kakuno et al., NIM A533, 516 (2004) B oscillations more Method tagging single r bin: two r bins: back

  41. H. Tajima et al., NIM A533, 370 (2004) B oscillations more Method resolution function Rful: vtx of fully reconstructed B meson Rasc: vtx of tagging B meson Rnp: non-primary tracks Rk: kinematic smearing back

  42. Vjb* Vid Vjd Vib* b d W+ b d B0 B0 u, c, t u, c, t u, c, t u, c, t B0 W- W+ B0 W- b d d b B oscillations more P0: any pseudo-scalar meson; specific example of Bd0 Phenomenology P0-P0 transition → box diagram at quark level if mi = mj  due to CKM unitarity: no mixing simplified treatment based on dimension: O. Nachtmann, Elem. Part. Phys., Springer-Verlag back for serious treatment see e.g.: A.J. Buras et al., Nucl.Phys.B245, 369 (1984)

  43. Belle, PRL97, 251802 (2006), 414 fb-1 Leptonic B decays more Systematic checks Bsigdecay modes check of EECL, double tagged decays, Bsig-→D*0l-n, D*0→D0p0 back

  44. Leptonic B decays more Type II Two Higgs Doublets Models (f1 gives masses to d-type and charged l; f2 gives masses to u-type; in Type I models f1 is decoupled and f2 generates all masses) Phenomenology additional Higgs doublet; tanb=v1/v2, ratio of vacuum expectation values; H± coupling  ml same factor as helicity SM suppression ratio independent of H ± contribution: W.S.Hou, PRD48, 2342 (1993) back if Gmeas>GSM H± contribution dominant

  45. Semileptonic B decays more Form factors P→P: B(v) → B(v’): for mb→  amplitude can only depend on g= v·v’; for v = v’ nothing happens, z(1)=1; B(v) → D(v’): for mb, mc→  same (HQS) z(v·v’): Isgur-Wise function relates two in principle independent form factors for P → P transition back

  46. Semileptonic B decays more Form factors P→V: q2 one more f.f. if ml not small; HQS: relations among f.f.’s for P→ P and P →V back

  47. M. Tanaka, Z.Phys.C67, 321 (1995) Semileptonic B decays more B →D*tnphenomenology amplitude for W exchange: lM=±,0; lt=±; lW=±,0; D*, t, W helicity amplitude for H± exchange: relation among H ±, W exchange amplitudes: H ± : no contribution of transversely polarized D* (HR,L±=0) back

  48. U. Nierste et al., PRD78, 015006 (2008) Semileptonic B decays more B →Dtnphenomenology update of predictions: measurement BaBar, PRL100, 021801 (2008), 209 fb-1 mB2/mH2 tan2b (in 2HDM-II) back

  49. b → sg more inclusive semil. B decays semil. width: Operator Product Expansion to O(1/mb2): two parameters, l1, l2: average p2 of b in B hyperfine interaction back

  50. b → sg more inclusive semil. B decays Fermi motion: new parameter L same parameters governing moments of various distributions, e.g. mass of hadronic system in semil. decays: or Eg moments in b →s g: A.F.Falk, M.E.Luke, PRD57, 424 (1998) A.Kapustin, Z. Ligeti PLB355, 318 (1995) back

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