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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. Helmholz 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 Helmholz 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 Part of B-factories lectures with A.J. Bevan; division by topics, not by experiments

  3. Introduction Dual role of charm physics - experimental tests of theor. predictions (most notably of (L)QCD); improve precision of CKM measurements (B physics); example: leptonic decays of D mesons → decay constants, tests of LQCD; Dr. Jeckyll - standalone field of SM tests and search for new phenomena (SM and/or NP); example: mixing and CPV in D0 system Mr. Hyde

  4. g* c c Introduction B-factory=charm factory s(c c)  1.3 nb (~109 XcYc pairs) + light qq production; perfect experimental environment for charm physics; increased interest in charm physics in recent years; jets of hadrons # papers in Spires with title “charm*” Charm is... a way of getting the answer yes without having asked any clear question. A. Camus (1913 - 1960) (17± 3)% increase year

  5. Vuj* Vci Vcj Vui* u c W+ u c D0 D0 d, s, b d, s, b d, s, b d, s, b D0 W- W+ D0 W- u c c u History observation of K0: 1950 (Caletch) mixing in K0: 1956 (Columbia) observation of Bd0: 1983 (CESR) mixing in Bd0: 1987 (Desy) observation of Bs0: 1992 (LEP) mixing in Bs0: 2006 (Fermilab) observation of D0: 1976 (SLAC) mixing in D0: 2007 (KEK, SLAC) (evidence of) D0 mixing D0 case only M0 system with down-quarks in loop 6 years 4 years 14 years 31 years c quark mass t quark mass ???? ???? (adopting eq. from lecture 1, B oscillations)

  6. D0 mixing Phenomenology |VcbVub*|<< |VcsVus*|, |VcdVud*| assuming unitarity in 2 generations  more precisely: G. Burdman, I. Shipsey, Ann.Rev.Nucl.Sci. 53, 431 (2003) DCS SU(3) breaking mixing parameters:

  7. u c K+ D0 D0 D0 K- D0 mixing Phenomenology 2nd order in pert. th.:: |x| ~ O(10-5) short distance: contributes to x; common statement: mixing with large x sign of NP; long distance: contributes to y andx; c u NP D0 y is affected by sum over real intermediate states; x also affected by sum over off-shell states; |x|, |y| ≤O(10-2) I.I. Bigi, N. Uraltsev, Nucl. Phys. B592, 92 (2001); A.F. Falk et al., PRD69, 114021 (2004) D0 mixing is a rare process The duration of passion is proportionate with the original resistance of the woman. H. de Balzac (1799 -1850)

  8. D0 mixing Time evolution simplified due to |x|, |y| << 1; various decay modes with specific decay t dependence; Common features D*+ →D0ps+ charge of ps flavor of D0; DM=M(D0ps)-M(D0) (or q=DM-mp)  background reduction p*(D*) > 2.5 GeV/c eliminates D0 from b → c

  9. D0 mixing Decays to CP eigenstates S. Bergman et al., PLB486, 418 (2000) D0→ K+K- / p+p- CP even final state; if no CPV: CP|D1> = |D1> t=1/G1; K-p+: mixture of CP states  t=f(1/G1,1/G2) AM, : CPV in mixing and interference (addressed later) Belle, PRL 98, 211803 (2007), 540fb-1 Reconstruction M(K+K- ) , q=M(K+K- ps)- M(K+K- )- M(p), st, selection optimized on MC more

  10. K+K-/p+p- and K-p+ratio Belle, PRL 98, 211803 (2007), 540fb-1 D0 mixing Decays to CP eigenstates simultaneous binned likelihood fit to decay-t, common free yCP c2/ndf= 1.084 (ndf=289) + 3.2 s (4.1 s stat. only) evidence for D0 mixing (regardless of possible CPV) confirmation: BaBar, arXiv:0712.2249, 384fb-1 yCP=(1.24± 0.39±0.13)% yCP currently most precisely measured param.

  11. D*+→ D0pslow+D0 → D0 → K+p- D0 mixing WS decays (non-CP) DCS decays  interference; t-dependence to separate DCS/mixed reconstruction NWS=4030±90; fit R: sum of 3 Gaussians; RS sample: t=(410.3±0.6) fs BaBar, PRL 98, 211802 (2007), 384fb-1 d: unknown strong phase DCS/CF WS sample

  12. D0 mixing WS decays (non-CP) Result x’2, y’ region BaBar, PRL 98, 211802 (2007), 384fb-1 evidence for D0 mixing RD = (3.03 ± 0.16±0.10 ) ·10-3 x’2= (-0.22 ±0.33±0.21) · 10-3 y’= (9.7 ±4.4±3.1) · 10-3 likelihood contours 3.9s 1s 2s 3s 4s 5s RD = (3.64 ± 0.17 ) ·10-3 x’2 = (0.18 ±0.210.23) · 10-3 y’= (0.6 ±4.03.9) · 10-3 95% C.L. (x’2, y’) contour frequentist, FC ordering Belle, PRL 96, 151801 (2006), 400fb-1 uncertainty includes syst. error

  13. D0 mixing t D0→KSp+p- t-dependent Dalitz analyses different types of interm. states; CF: D0→ K*-p+ DCS: D0→ K*+p- CP: D0→r0 KS if f = f  populate same Dalitz plot; relative phases determined (unlike D0→ K+p-); t-dependence: regions of Dalitz plane→ specific t dependence f(x, y); D0→f l1,2=f(x,y); n.b.:K+p-:x’2, y’ m±2 = m2(KSp±), D0→f access directly x, y sum of intermediate states:

  14. K*X(1400)+ D0 mixing t-dependent Dalitzanalyses Nsig= (534.4±0.8)x103 P95% Dalitz fit projections; decay-t fit projection; Belle, PRL 99, 131803 (2007), 540fb-1 K*(892)+ r/w K*(892)- t= (409.9±0.9)fs most sensitive meas. of x more t [fs]

  15. Vus* D0 mixing K+ CP violation Vcs D0 D0: first two quark generations; CKM elements ≈ real; using CKM unitarity: bellow current exp. sensitivity; signals New Physics K- parameterization: RD ≠1: Cabbibo suppression AD ≠0: CPV in decay AM ≠0: CPV in mixing f ≠0 : CPV in interference more

  16. D0 mixing CP violation Decays to CP states with adec<<1: Belle, PRL 98, 211803 (2007), 540fb-1 t-dependent BaBar, arXiv:0712.2249, 384fb-1 ACPpp ACPKK t-integrated ACPmeas =Aep + AFB + ACPf Aep: comparison of tagged/untagged (D*+→D0p+),D0→K-p+ AFB: asymmetric f(cosqCMS) BaBar, PRL 100, 061803 (2007), 386fb-1 |cosqCMS| |cosqCMS| AFBpp AFBKK Belle, arXiv:0807.0148, 540fb-1 more more |cosqCMS| |cosqCMS|

  17. D0 mixing CP violation WS decays (non-CP) BaBar, PRL 98, 211802 (2007), 384fb-1 • separate D0 and D0 tags; • fit (x’2,y’,RD) → (x’±2, y’±,RD±); consistent with 0 x10-3 consistent consistent Belle, PRL 96, 151801 (2006), 400fb-1 AD = (23 ± 47) ·10-3 AM = (670 ± 1200) ·10-3 t-dependent Dalitz analyses additional free param, |q/p|, f; Belle, PRL 99, 131803 (2007), 540fb-1

  18. Don't keep mixing in these other things. It only confuses. D0 mixing K. Kinski (1926 - 1991) Average of results K+K- c2 fit including correlations among measured quantities K+p- RM KSp-p+ d uncertainty c2/n.d.f.= 23.5/18 CPV http://www.slac.stanford.edu/xorg/hfag/charm/ (x,y)≠(0,0): 6.7s; CP even state heavier and shorter lived; no CPV within 1s n.b.: x(D0) ≈0.01; x(K0) ≈1; x(Bd) ≈ 0.8; x(Bs) ≈ 25;

  19. D0 mixing E. Golowich et al., PRD76, 095009 (2007) Constraints on NP D0 uncertain SM predictions for x, y; measured values can impose constraints on NP models parameter space; e.g. R-parity violating SUSY; existing constraints largely improved for many NP models D0 D0 D0 Approximate sensitivity SuperB, L = 5 ab-1 x s(x)s(y) s(|q/p|)s(f) 0.1% 0.1% 0.1 0.1 x=2% LHCb, L = 10fb-1 Prediction is very difficult, especially of the future. s(x’2)s(y’) 6x10-5 0.1% N. Bohr (1885 - 1962) x, y accuracy ~3x better than current WA; sensitivity to CPV would cover range of SM predictions l’12kl’11k R-parity violating coupling const.

  20. K p p g e- e+ Ds leptonic decays Ds→mn analogy of B leptonic decays, see Lecture 1; check of LQCD (fP) ? Method: inverse (recoil) reconstruction D →Knp, n=1,3 relative charge (Kprim, D)/Ds* right-, wrong-sign Ds* Belle, PRL 100, 241801 (2008), 548fb-1 additionalparticles D g Ds µ n p p p K Kprim signal tag M(Ds)=Mrec(DKprimXg) full recon. recon. in recoil inclusive Ds signal (no m requirement) M2(n)=M2rec(DKprimXgm) Ds→ mn signal efficiency depends on # primary particles: nX = 3 (DDs*Kprim) + N differences data/MC

  21. e- e+ Ds* →Dsg Ds→ fp N=2093±99 Ds leptonic decays µ Ds→mn Method fit data M(Ds) distr. with MC signal in bins of nXrec; bkg. from WS inclusive Ds normalization; Method fully reconstruct tag side Ds,D+,D0,D*+; m,g; pn from pmiss with m(n,m)mDs; signal in DM=M(mng)-M(mn) (~ mDs*-mDs); exact Ds production in cc not known normalization: Ds→fp D tag Ds* Ds g n Belle, PRL100, 241801 (2008), 548fb-1 BaBar, PRL98, 141801 (2007), 230fb-1

  22. Ds* →Dsg Ds→ mn N=489±55 Ds leptonic decays Ds→mn Signal fit data M(n) distribution with MC signal in bins of nXrec; bkg. from Ds→en Belle, PRL100, 241801 (2008), 548fb-1 edependence reduced (single track (m) recon.) Br(Ds→mn) = (6.44 ± 0.76 ± 0.56) x10-3 BaBar, PRL98, 141801 (2007), 230fb-1 Br(Ds→mn) = (6.74 ± 0.83 ± 0.26 ± 0.66) x10-3 last uncertainty Br(Ds→fp) using |Vcs| = 0.9730 ± 0.0002 from overall fit including unitarity (PDG) Belle, PRL100, 241801 (2008), 548fb-1 fDs = (275 ± 16 ± 12) MeV fDs = (283 ± 17 ± 7 ± 14) MeV BaBar, PRL98, 141801 (2007), 230fb-1

  23. Ds leptonic decays Ds→mn Average of absolute meas.; huge improvement in LQCD accuracy; agreement for fD+: LQCD: 208 ± 4 MeV exp.: 223 ±17 MeV (but exp. error larger than for fDs) Belle, PRL100, 241801 (2008), 548fb-1 Cleo-c, PRL99, 071802 (2007), 314pb-1 m, t (pn) Cleo-c, PRL100, 161801 (2008), 298pb-1 t (enn) aver. 274 ±10 MeV MILC, PRL95, 122002 (2005) LQCD 241 ±3 MeV HPQCD, UKQCD, PRL100, 062002 (2008) 230 240 250 260 270 280 290 300 MeV 3.3 s discrepancy to do list: confirm LQCD uncertainty; reduce exp. uncertainty; more

  24. Spectroscopy Production @ B-factories open and hidden charm; clean exp. environment; various methods related to different prod. mechanisms; rich harvest of previously unknown states at B-factories; only few (“exotic”) examples discussed; spectroscopy: tests of QCD, bounding q’s and g’s in hadrons b c Vcb c B Vcs* s q q open charm (Ds**, D**,...) colour suppressed; hidden charm (cc, charmonium-like...) e+ Vq1q2* e+ q1 g c q2 g b c e+ Vcb g* X continuum (double cc) (also lectures by V. Barguta) e- e- e- c B g c c e+ g* q q e- X initial state radiation (1-- states) two photon processes

  25. Spectroscopy Exotic states states other than q1q2, q1q2q3 not forbidden in SM; exotic JPC (e.g. 0+-, 1-+, 2+-,... forbidden for qq); exotic decay modes (not possible from qq); strange properties (widths,...); pentaquarks: q1q2q3q4q5; hybrids: cc + g’s; tetraquarks: diquark-antidiquark, [cq][cq] molecules: M(cq)M(cq), loosely bound mesons ...Life is like a box of chocolates, you never know...: Forrest Gump (1994)

  26. Belle, PRL 91, 262001 (2003), 140fb-1 Spectroscopy X(3872) observed in B decays, B →(J/ypp)K; charmonium-like; well established state; b c Vcb c B Vcs* s q q Mbc in 5 MeV bins of M(p+p-J/y) Belle, hep-ex/0505038, 250fb-1 K

  27. CDF, PRL96, 1 02002 (2006), 360pb-1 Spectroscopy X(3872) properties C=+1; M(pp) distrib., r-like; (cc) →J/yr isospin breaking; 4-quark states: hc’’: ang. distr., M, G; cc0’: ang. distr., DD; cc1’: gJ/y hc2: pphc dominant, DD*; cc2’: DD*; no obvious cc candidate; hc” cc1’ y2 y3 MD+MD* hc’ hc2 y” y’ Belle, hep-ex/0505037, 250fb-1 hc’ cc2 hc cc1 cc0 cc2’ J/y hc ang. distrib.: Belle, hep-ex/0505038, 250fb-1 more JPC= 1++, 2-+ favoured;

  28. Belle, PRL97, 162002 (2006), 414 fb-1 Spectroscopy B+→ X(D0D0p0)K+ X(3872) other possibilities (see also lectures by V. Lyubovitskij) DD* molecule: isospin breaking; JPC=1++; J/ypp favoured over DDp; R~0.1 E. Braten, M. Lu, PRD77, 014029 (2008); see also E.S. Swanson, Phys. Rept. 429, 243 (2006) for review Belle, PRL97, 162002 (2006), 414 fb-1 last uncertainty: mD0; main syst.: p0 calibration and signal shape Belle, hep-ex/0505037, 250fb-1 B+→ X(D*0D0)K+ BaBar, PRD77, 111102 (2008), 347 fb-1 J=2 decays to DD* suppressed by (p*)2L+1 with L=1,2; 1++ state favoured more

  29. M(J/ypp) for B →XK Spectroscopy K+ X(3872) other possibilities DD* molecule: prod. from B0 suppressed compared to B+ (depending on model parameters); tetraquarks: two mixed states, [cu][cu], [cd][cd]; one produced mainly in B0, other in B+ decays  mass difference; also charged X+ [cu][cd], no evidence so far; It is characteristic of wisdom not to do desperate things. H.D. Thoreau (1817 - 1862) Ks Belle, BELLE-CONF-0711, 605 fb-1 K+ BaBar, PRD77, 111101 (2008), 413 fb-1 L. Maiani et al., PRD71, 014028 (2005) Ks more

  30. Spectroscopy • Z+(4430) • B →(y’p+)K; • y’ →ll, J/ypp; • Dalitz plot; • K* veto; •  M(y’p+); • fit: BW + phase space; • signal stable in subsamples, • w.r.t. K* veto, etc.; • known S-, P- and D-wave Kp • resonances tried, cannot • reproduce the peak; • first charged charmonium-like • resonance; Belle, PRL100, 142001 (2008), 605 fb-1 N=121 ± 30 6.5 s L.Maiani et al., arxiv:0708.3997 J. Rosner, PRD74, 114002 (2007) C. Meng et al., arxiv:0708.4222 possibilities: tetraquark, radial excitation of X+(3872) (JP=1+; neutral partner?); D*D1(2420) threshold effect; D*D1(2420) molecule (JP=0-,1-,2-;decays to D*D*p?) more

  31. Summary B-factories successfully perform the precision measurements in determination of SM processes as a complement to direct NP searches (starting on Sep. 10) SM stands, although hints (~3 s) of discrepancies are seen B-factories have outreached the program as foreseen at the start B oscillations in conjunction with breakthrough in Bs confirms SM to a high accuracy leptonic and radiative B decays constrain NP but large room for improvement from SuperB Important results in charm D0 mixing and CPV another milestone achieved, need more precise measurements and predictions Ds leptonic decays testing LQCD Spectroscopy may need extensions

  32. D0 mixing more CPV parameterization three types of CPV RD ≠1 Cabbibo supp. AD≠ 0direct CPV • sign due • to relative sign of • Vus and Vcd; AM≠ 0CPV in mixing f≠ 0CPV in interf. back back

  33. D0 mixing more Decays to CP eigenstates D0→ K+K- / p+p- to linear order: back

  34. D0 mixing more Decays to CP eigenstates D0→ K+K- / p+p- since AD<<1 1/G=tf=t/(1+yCP); yCP=(t/tf)-1=y cosf-Amx sinf if same procedure applied separately to D0 and D0 lifetime: back back

  35. K-p+ D0 mixing more Decays to CP eigenstates D0→ K+K- / p+p- Fit simultaneous binned likelihood fit to K+K-/K-p+/p+p- decay-t, common free yCP event-by-event st R : ideally each si Gaussian resol. term with fraction fi; : described by 3 Gaussians  trec-tgen/st parameters of R depend slightly on data taking conditions back t = 408.7±0.6 fs

  36. method of D0 mixing more BaBar, PRL 100, 061803 (2007), 386fb-1 Decays to CP eigenstates t-integrated CPV in D0→ K+K- / p+p- Aep from comparison Auntag/Atag =0 (strong int.) =0 (same for D0, D0) back

  37. D0 mixing more Decays to CP eigenstates t-integrated CPV in D0→ K+K- / p+p- Belle, arXiv:0807.0148, 540fb-1 Aep (pp,cosqp) back

  38. M signal rnd slow p combin. Belle, PRL 99, 131803 (2007), 540fb-1 D0 mixing more t-dependent Dalitzanalyses selection; Dalitz model; 13 BW resonances, non-resonant contr.; comb. bkg.: from M sideband test of S-wave pp contr. (f0, s1,2): K-matrix formalism Results (fit fractions, phases) in agreement with (measurement of f3) Belle, PRD73, 112009 (2006) back

  39. D0 mixing more t-dependent Dalitz analyses Belle, PRL 99, 131803 (2007), 540fb-1 model dependence [10-4]: Dx                 Dy -10.3           +0.1K*0(1430) DCS/CF -15% + 6.9           -2.5K*2(1430) DCS/CF -30% -1.6 -0.9 K*(1410) DCS & CF -20% -5.1 -4.1G(q2) const. --------------------------------- +10+6        Total model dep. -14-8 experimental: Dx           Dy +7.6         -7.8               p* variation -5.6         -5.7  Dalitz pdf for bkg. from different t bins ----------------------- +9+8 Total experimental-7          -12 Largest systematics observed discrepancy from input in MC statistical uncertainty: s(x)=29x10-4 s(y)=24x10-4 back

  40. D0 mixing more t-dependent Dalitz analyses Belle, PRL 99, 131803 (2007), 540fb-1 efficiency and resol. in M(pp) rnd ps bkg.: Prnd [(1-fw) M(m-2,m+2,t) +fwM(m+2,m-2,t)] R(t) fw from fit to Q side band: fw= 0.452 ± 0.005 diff. w.r.t. fw=0.5 in systematic error comb. bkg.: Pcmb  B(m-2,m+2) * ([ d(t) + Exp(t) ]R’(t) parameters from fit to Dalitz and t distrib. of M(KSp+p- ) sideband (systematics: Dalitz distrib. in different t intervals) back

  41. Cleo-c Ds tags, 2.5% 0.5 1.0 1.5 2.0 L / fb-1 Ds leptonic decays more • Ds→mn • projection • B factories with 2 ab-1 • ~4% uncertainty on fDs; • Charm-factory: syst. on Ds tags? • test of LQCD to ~2-3%; • possible NP effects: Belle, PRL100, 241801 (2008), 548fb-1 Cleo-c, PRD 76, 072002 (2007) B.A. Dobrescu, A.S. Kronfeld,, PRL100, 241802 (2008) M: NP mass back

  42. Spectroscopy more Belle, hep-ex/0505037, 250fb-1 X(3872) B →KX (J/yg): B →Kcc1(J/yg) calibration; B →KX (J/ypp): B →Ky(2S) calibration; B →KX (J/yppp0): no. of B’s in bins of M(gJ/y) 13.6±4.4 evts.(4s) Belle, BELLE-CONF-0711, 605 fb-1 Belle, hep-ex/0505037, 250fb-1 no. of B’s in bins of M(ppp0) 13.1±4.2 evts.(6.4s) M(p+p-p0)>750 MeV back

  43. Spectroscopy more X(3872) tetraquarks: predicted spectrum; mass difference; q: mixing angle DD* molecule: wave function fractions L. Maiani et al., PRD71, 014028 (2005) E.S.Swanson, PLB588, 189 (2004) Zi back back binding energy

  44. Spectroscopy more p Z+(4430) S-, P-, D-wave interference: Belle, PRL100, 142001 (2008), 605 fb-1 qp y’ K interference +1.0 22 GeV2 incoherent (4.43)2 GeV2 0.25 cosqp M2(py’) cannot produce a single peak at cosqp ~ 0.25 16 GeV2 -1.0 back

  45. A. Roodman, JPS/DPF meeting, Hawaii 06 SuperB more Two approaches energy frontier sesnitivity frontier Competitiveness not to underestimate power of precision measurements back

  46. SuperB more 2 Some physics motivation different models for NP; in any case precise meas. of observables  test specifically for this mode: SM expect. for Dsin2F1: 0 ± 2% current sens.: 6% (b →sqq) current lum.: 1.2 ab-1 needed: >10 ab-1 NP tree dominated 2 proposed for Super B-factory NP penguin dominated back

  47. SuperB more More examples of physics motivation Complementarity Super KEKB Physics working group back

  48. SuperB more Proposed luminosity Super KEKB: 8x1035 cm-2 s-1 crab cavities Frascati: ~1036 cm-2 s-1 back

  49. H. Koiso, Inaugural meeting of Super Belle SuperB more β*y = σz = 3 mm SuperKEKB e- 9.4 A Crab cavities will be installed and tested with beam in 2006. e+ 4.1 A The state-of-art ARES copper cavities will be upgraded with higher energy storage ratio to support higher current. The superconducting cavities will be upgraded to absorb more higher-order mode power up to 50 kW. The beam pipes and all vacuum components will be replaced with higher-current-proof design. will reach 8 × 1035 cm-2s-1.

  50. H. Koiso, Inaugural meeting of Super Belle SuperB more

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