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New Resonances from B-factories

New Resonances from B-factories. J. Brodzicka (KEK) for Belle KEKTH’07, Tsukuba. A lot of states, a lot of production processes…. J. Brodzicka for Belle @ KEKTH’07. B-Factories are Charmonium factories. J. Brodzicka for Belle @ KEKTH’07. e + e +

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New Resonances from B-factories

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  1. New Resonances from B-factories J. Brodzicka (KEK) for Belle KEKTH’07, Tsukuba

  2. A lot of states, a lot of production processes… J. Brodzicka for Belle @ KEKTH’07

  3. B-Factories are Charmonium factories J. Brodzicka for Belle @ KEKTH’07 e+ e+ e- e- X D D b c u, dc s u, d BX W K(*) c γ* c c c e+ J/ψ X e- γISR γ* π π J/ψ γ γ X e+ e- cc (-like) production mechanisms @ B-Factory • B meson decays i.e. B→XccK(*) • e+e- radiative return (ISR) e+e-→γISRXcc→γISR J/ψππ • e+e- annihilation i.e. double cc • production e+e-→J/ψXcc • γγ collision e+e-→γγ→Xcc→DD

  4. J. Brodzicka for Belle @ KEKTH’07 A lot of data from KEK-B Factory… • Asymmetric e+e- collider Tsukuba • e+: 3.5 GeV  e-: 8.0 GeV • CM energy: 10.58 GeV at (4S) • e+e-  (4S)  BB • Advantages: • exclusive source of BB pairs • useful kinematical constraints • high signal-to-background ratio • separation of B decay vertices • Record luminosity peak: 1.711034cm-2s-1 • Integrated luminosity: ~750 fb-1 • ~ 780 * 106 BB • ~ 960 * 106 cc • Beauty and Charm Factory

  5. …recorded with the Belle detector J. Brodzicka for Belle @ KEKTH’07 Aerogel Cherenkov Counter Time of Flight Counter Central Drift Chamber SC Solenoid 1.5T KL /Detector Silicon Vertex Detector Electromagnetic Calorimeter • Event reconstruction • Charged tracks • Central Drift Chamber • Silicon Vertex Detector • Electrons and photons • Electromagnetic Calorimeter 3.5 GeV e+ • Particle identification • K/ separation • Central Drift Chamber: dE/dx • Aerogel Cherenkov Counter • Time of Flight Counter • Electron identification • Electromagnetic Calorimeter KL and  identification • KL and muon detector Vertexing • Silicon Vertex Detector 8 GeV e-

  6. B decays as a charmonium-like factory J. Brodzicka for Belle @ KEKTH’07 b c u, dc s K(*) u, d B charmonium (-like) Wη, χc, J/ψ, ψ’… Good place for spectroscopy study! Cabbibo-favored vertices • B→XccK(*) decays used: • b→cW→ccs is dominant process (exclusive BF ~10-3) • background reduction is possible • JP of parent B is known → JP of the child particles can be determined from angular analysis • J=0, 1 states should dominate (if factorization assumed)

  7. How to identify B meson signal J. Brodzicka for Belle @ KEKTH’07 ΔE Mbc ΔE Mbc • We take advantage of e+e-→(4S) → BBkinematics m(4S)~ mB +mB no accompanying particles → EB=Ebeam=√s/2in cms • kinematical variables used in B-Factories Mbc= √E2beam- p2B beam-constrained mass (signal at mB~5.28GeV) ΔE=EB- Ebeam cms energy difference (signal peaks at 0) • Resolution improvement (Ebeam is precisely known) • Background separation Example: B0→ J/ψ KS

  8. Reminder on X(3872) J. Brodzicka for Belle @ KEKTH’07 Ψ(2S)→J/ψππ 152M BB X(3872)→J/ψππ M(J/ψπ+π-) 117MBB • X(3872)→J/ψπ+π- observed in B+→X(3872)K+ by Belle • confirmed by BaBar, CDF, D0 PRL91, 262001 (2003) BF(B→KX)*BF(X→J/ψππ) = (1.3±0.2±0.1)*10-5

  9. Properties of X(3872) J. Brodzicka for Belle @ KEKTH’07 M(π+π-) • mX=3871.2 ± 0.5MeV ≈mD*0+mD0 (PDG06) • narrow: Γ<2.3MeV • above DD threshold but no X→DD found PRL93, 051803 (2004) • M(π+π-) is like ρ(770), so X(3872)→J/ψρ? • Other decay modes: J/ψγ,J/ψω • Favored JPC= 1++ (angular analysis by Belle/CDF, decay modes) What is X(3872)? • cc? Does not match any cc predicted by quark models • DD* molecule? mX-(mD*0+mD0)= -0.6±0.6 MeV above/below DD*? • 4-quark? Would explain small width. Charged X should exist

  10. Is X(3872) a cc state ? J. Brodzicka for Belle @ KEKTH’07

  11. X(3872)in B+ and B0 decays J. Brodzicka for Belle @ KEKTH’07 B0→XK0s Ns=30±7 (6.5σ) B+→XK+ Ns=125±14 (12σ) First observation! 657MBB M(J/ψπ+π-) M(J/ψπ+π-) BELLE-CONF-0711 • Study of X(3872)→J/ψπ+π-inB+→XK+ and B0→XK0s (657M BB) • control sample: B→ψ’K ψ’→J/ψππto calibrate mass & resolution • afterMbc andΔE selection: • similar properties of X(3872) from B+ and B0 decays (this disfavors some theoretical models)

  12. X(3872)→DD* J. Brodzicka for Belle @ KEKTH’07 N=24±6 (6.4σ) N=33±7 (4.9σ) • X(3872) is very close to D*0D0 threshold • BaBar: B+→D*0D0K D*0 →D0π0,D0γ(383MBB) • Belle: B+→D0D0 π0K(447MBB) • mass ~4σ above M(X) for X→J/ψππ • are there two states X(3872) and X(3875)? hep-ex/0708.1565 PRL97, 162002(2006) M(X)=3875.1+0.7-0.5 ±0.5 MeV Γ=3.0+1.9-1.4 ± 0.9 MeV M(X)=3875.4 ± 0.7+0.4-1.7 ±0.9 MeV

  13. What is X(3872)? J. Brodzicka for Belle @ KEKTH’07 u c d c Xu= Xd= u c d c • 4-quark model: Xu[uc][uc] state decaying to D0D0π0 = X(3875) Xd[dc][dc] state decaying to J/Ψπ+π-= X(3872) Finding charged partner is critical • Molecule model: X is D*0D0 bound state (mX ≈ mD*0+ mD0) Favors DDπ over J/ψππ Line shape depends on the decay channel • X(3872) properties still under investigation (mass, width, line shape, decay modes…) Maiani, Polosa et al. hep-ph/0707.3354 Braaten et al. hep-ph/0710.5482

  14. Recently… J. Brodzicka for Belle @ KEKTH’07

  15. Observation of Z+(4430)→ψ’π+ J. Brodzicka for Belle @ KEKTH’07 hep-ex/0708.1790 Submitted to PRL • Belle studied B0 →ψ’π+K- and B+→ψ’π+K0s(657M BB) • ψ’→ e+e-, μ+μ- or J/ψπ+π- J/ψ →e+e-, μ+μ- • secondary particles combined to B→ψ’π+K candidates • Mbc andΔE selection: clear B→ψ’π+K signal

  16. Observation of Z+(4430)→ψ’π+ J. Brodzicka for Belle @ KEKTH’07 ??? M2(ψ’π+) K2*(1430) K*(890) M2(Kπ+) • in B→ψ’π+K Dalitz plot: • K*→π+K states and a clear band at M2(ψ’π+)~20GeV2 • K*veto applied to study of ψ’π+(both K* regions excluded) • M(ψ’π+) fit: Breit-Wigner + ph.space like function prominent peak (K* veto applied) 3-body decays non-B background Z+(4430) N=121±30 (6.5σ) M(ψ’π+) M= 4433 ± 4 MeV Γ= 45+18-13 MeV

  17. Z+(4430) →ψ’π+ J. Brodzicka for Belle @ KEKTH’07 • Z(4430) signal is robust: • B generic MC studied → Z(4430) is not a reflection • data subsets checked, K* veto changed • interference between Kπ partial waves (S,P,D) → cannot produce such narrow peak in ψ’π+ M= 4433 ± 4 ± 2MeV Γ= 45 MeV +18 +30 –13 -13 Z+(4430) BF(B→KZ)*BF(Z→ψ’π+) = (4.1 ±1.0±1.4 )*10-5 JP not determined, statistics too low • First candidate for a charged cc-like state! Must be exotic! • Z(4430) could be a tetraquark state [cu][cd] (Charged states naturally appear in 4-quark models) Radial excitation of X(3872/5) family? Maiani, Polosa et al. hep-hp/0708.3997

  18. Y(3940)→J/ψω from Belle J. Brodzicka for Belle @ KEKTH’07 K*’s Y(3940) N=58±11 M2(ωJ/ψ) M(ωJ/ψ) M2(ωK) PRL 94, 182002 (2005) • Study of B→ KJ/ψω(275M BB) • J/ψ→ee, μμω→π+π-π0 • Mbc, ΔE and M(π+π-π0) selection • M(ωK)>1.6GeV: K* veto • Y is above DD threshold but has large cc transition • Candidate for cc-gluon hybrid? (but hybrids predicted above 4GeV) M= 3943±11±13 MeV Г=87±22±26 MeV BF(B→KY)*BF(Y→J/ψω) =(7.1±1.3±3.1)*10-5

  19. Y(3940) confirmed by BaBar J. Brodzicka for Belle @ KEKTH’07 B+→K+ J/ψω B0→K0 J/ψω M(J/ψω) M(J/ψω) hep-ex/0711.2047 submitted to PRL • Similar study of B→ KJ/ψω(383M BB) • But events weighted according to helicity distribution expected for ω→π+π-π0(~sin2θ) (projects the signal, reduces background) • Fit to acceptance corrected M(J/ψω) • M= 3914 ±4 ±2 MeV Г= 33 ±5 MeV mass and width smaller than Y(3940) from Belle BF(B+→K+Y)*BF(Y→J/ψω)=(4.9±1.0±0.5)*10-5 BF(B0→K0Y)*BF(Y→J/ψω)<3.9*10-5 M(π+π-π0) Mbc ΔE +12 – 8

  20. Double cc production: e+e-→J/ψ(cc)res J. Brodzicka for Belle @ KEKTH’07 c γ* c c c e+ J/ψ X e- PRL 98, 082001 (2007) • Factory of 0++ and 0-+ charmonia • Method: reconstruct J/ψ, study recoil mass Mrecoil(J/ψ) =√(Ecm-E J/ψ)2 -p2J/ψ • Surprises: below DD: cc states with large x-sections O(10-20fb) above DD: new state X(3940) • Method is limited: σ~30MeV; remainder system not reconstructed → its identification indirect N=266±63 (5σ) M=3936±14 MeV Γ=39±26 MeV one state or more? 357fb-1 BF(X(3940)J/ψω)<26%@90%CL so X(3940) it’s not Y(3940)

  21. Double cc production: e+e-→J/ψD(*)D(*) J. Brodzicka for Belle @ KEKTH’07 • D(*)D(*) resonances through e+e-→J/ψ D(*)D(*) • Reconstruct J/ψ and one D(*) , study Mrecoil(J/ψD(*) ) • Associated D(*) seen as peak in Mrecoil(J/ψD(*)) • Tagged processes: J/ψDD , J/ψDD* , J/ψD*D* (all >5σ) Mrec(J/ψD) DD*D*π 693fb-1 Mrec(J/ψD*) DD* hep-ex/0708.3812 submitted to PRL

  22. Double cc production: e+e-→J/ψD(*)D(*) J. Brodzicka for Belle @ KEKTH’07 ee→J/ψDD Mrec(J/ψD) DD*D*π M(DD) • Constrain Mrecoil(J/ψD(*)) from the peak regions to the nominal mass of associated D(*) • Tagged & constrained: e+e-→J/ψ D(*)D(*) so Mrecoil(J/ψ) = M(D(*)D(*)) • M(DD) is not non-resonant • one broad resonance or more? • fit unstable, significance low • remains inconclusive

  23. X(3940) and X(4160) J. Brodzicka for Belle @ KEKTH’07 Mrec(J/ψD) DD*D*π Mrec(J/ψD*) DD* ee→J/ψDD* X(3940) 6.0σ ee→J/ψD*D* X(4160) 5.5σ M(D*D) M(D*D*) N= 52 M =3942 ± 6 MeV =37 ± 12 MeV +24 –16 N= 24 M = 4156 ± 15 MeV = 139 ± 21 MeV +12 – 8 +7 –6 +25 –20 +26 –15 +111 – 61 • X(3940)→DD* visible in inclusive Mrecoil(J/ψD) • X(4160) →D*D* one more particle (C=+1 so it’s not ψ(4160)) • Possible assignments: ηc(3S) ηc(4S)

  24. Y family from ISR studies J. Brodzicka for Belle @ KEKTH’07 M = 4259 ± 8 MeV = 88 ± 23 MeV (Y→ee)*B(Y→J/ψππ)=5.5± 1.0 eV +2 –6 +6 –4 +0.8 –0.7 PRL 95, 142001 (2005) for 232fb-1 CLEO PRD74, 091104 (2006) CLEO-c PRL 96, 162003 (2006) for 13pb-1@4.26GeV Y(4260)→J/ψππ Y(4350)→ψ’ππ PRL 98, 212001 (2007) for 298fb-1

  25. Y→J/ψππ via ISR J. Brodzicka for Belle @ KEKTH’07 Y(4260) Ψ’ γISR γ* π π J/ψ X e+ e- PRL 99, 182004 (2007) • ISR gives access to JPC=1-- states • Study of e+e-→J/ψπ+π- γISR(548 fb-1) • Selection: J/ψ→ee, μμ + ππ; no extra tracks • ISR photon is not detected • Missing mass used to identify process • In M(J/ψππ): ψ’ signal and two clusters of events

  26. Y→J/ψππ via ISR J. Brodzicka for Belle @ KEKTH’07 PRL 99, 182004 (2007) • Fit to M(J/ψππ) with two interfering Breit-Wigners • Two solutions (destructive/constructive interference) • Y(4260) confirmed • Y(4008) broad state? Re-scattering from DD*? Coupled-channel effect? Non-resonant component? Y(4260) Y(4008)

  27. J/ψππfrom ISR studies J. Brodzicka for Belle @ KEKTH’07 • Using ISR we can measure hadronic x-sections in wide energy range • Model independent measurement • M(J/ψππ): background subtracted, corrected for efficiency and luminosity → Cross-section for e+e-→J/ψπ+π-

  28. Y→ψ’ππ via ISR J. Brodzicka for Belle @ KEKTH’07 Y(4360) new PRL 99, 142002 (2007) • Belle studied e+e-→ψ’π+π- γISR(673 fb-1) • ψ’→J/ψππ, J/ψ→ee, μμ + ππ; no extra tracks • γISR not detected • Very low background • Two significant peaks observed in M(ψ’ππ) • One close to Babar’s Y(4360) but more narrow

  29. Y→ψ’ππ via ISR J. Brodzicka for Belle @ KEKTH’07 PRL 99, 142002 (2007) • M(ψ’ππ)fitted with two coherent Breit-Wigner functions • Two solutions (for destructive/constructive interference) Y(4360) Y(4660)

  30. e+e-→J/ψKKvia ISR J. Brodzicka for Belle @ KEKTH’07 hep-ex/0709.2565 to appear in PRD • Belle studies e+e-→J/ψKK γISR(673fb-1) • First observation of e+e-→J/ψK+K- γISR and evidence for e+e-→J/ψKsKs γISR • M(J/ψKK) inconclusive

  31. 1 - - Y states via ISR J. Brodzicka for Belle @ KEKTH’07 p+p- J/y • l Y(4260) Y(4008) Y(4660) Y(4360) p+p-y’ K+K- J/y

  32. Do Y states decay to D(*)D(*) ? J. Brodzicka for Belle @ KEKTH’07 Y(4260) Y(4360) Y(4660) DD D*D σ(nb) D*D* • All Y states above DD, should decay to D(*)D(*) • Y states do not match well to peaks in hadronic x-sections • This means large partial widths to ψππ (unlike for ordinary cc) ψ(4040) ψ(4160) ψ(4415) PRL 98, 092001 (2007) hep-ex/0708.0082 to appear in PRD(RC)

  33. Look for Yb : bb counterpart of Y(4260) J. Brodzicka for Belle @ KEKTH’07 “Y(5S)”→Y(3S)ππ “Y(5S)”→Y(1S)ππ Y(3S) “Y(5S)”→Y(2S)ππ Y(2S) “Y(5S)”→Y(1S)ππ Y(1S) “Y(5S)”→Y(2S)ππ hep-ex/0710.2577 • If bb follows the pattern in cc , Yb should exist: Yb→Y(nS)ππ • Proposal: study of Y(5S) data • Belle collected 21.7 fb-1 at √s~10.87GeV • Only one energy point. At Y(5S) or nearby? Let’s call it “Y(5S)” • “Y(5S)”→Y(nS)π+π- Y(nS)→μ+μ- • ΔM= M(Y(mS))-M(Y(nS))=M(μμππ)-M(μμ) m>n Hou, PRD74, 017504 (2006)

  34. Huge Y(5S)→Y(nS)ππ Do we see Yb? J. Brodzicka for Belle @ KEKTH’07 Process Yield σ(pb) BF(%) Г(MeV) “Y(5S)”→Y(1S)ππ 325±20 1.6±0.1±0.1 0.53±0.03±0.05 0.59±0.04±0.09 “Y(5S)”→Y(2S)ππ 186±15 2.3±0.2±0.3 0.78±0.06±0.11 0.85±0.07±0.16 “Y(5S)”→Y(3S)ππ 10±4 1.4±0.5±0.2 0.48±0.18±0.07 0.52±0.20±0.10 assuming Y(5S)@10.87GeV σ=0.302±0.015nb Large! • Large Y(5S)→Y(nS)ππ partial widths! For other bb: O(keV) • Do not agree with hypothesis for pure bb state • Is it Yb? Mixture of Y(5S) and Yb? • Energy scan around Y(5S) needed

  35. Ys: strange version of Y(4260)? J. Brodzicka for Belle @ KEKTH’07 • Y(2175)→f0(980) φ from BaBar (confirmed by BESII) confirmed by BESII PRD74, 091103 (R) (2006)

  36. Z(3930) from γγ J. Brodzicka for Belle @ KEKTH’07 e+ e+ e- e- X D D γ γ PRL 96, 082003 (2006) • Only C=+1 states produced • ee→γγ→DD studied (395fb-1) • Peak observed M(DD)~3.93GeV • N=64±18 M=3929±5±2MeV Г=29±10±2MeV • Гγγ*BF(Z→DD)=0.18± 0.05±0.03 keV (for J=2) • Spin-2 favored over spin-0 by helicity distribution • Z(3930) isχ’c2 candidiate Z(3930) J=2 J=0

  37. A lot of XYZ states… J. Brodzicka for Belle @ KEKTH’07 • ll

  38. cc (-like) state of art J. Brodzicka for Belle @ KEKTH’07 Y(3360), Y(3660) ηc(4S) • We added a few new states… • Are they cc? Do we understand them?

  39. Summary J. Brodzicka for Belle @ KEKTH’07 • Do we see new charmonium spectroscopy @4GeV? • There are good candidates for hybrids, multiquarks Y(3940) X(3872) Z(4430) Y-family… • XYZ spectroscopy in s and b quark sectors? Yb, Ys?

  40. Lots of pieces… J. Brodzicka for Belle @ KEKTH’07 Y(3940) Z(4430) X(4160) Are they all from the same puzzle? Y(4660) Y(4008) Y(4260) Y(4360) X(3872)

  41. J. Brodzicka for Belle @ KEKTH’07 Backup

  42. Yb counterpart ? J. Brodzicka for Belle @ KEKTH’07 • M(ππ) and cosθhel studied Brown-Cahn (CLEO) model (grey) generic phase space (open)

  43. Double cc production: e+e-→J/ψ(cc)res J. Brodzicka for Belle @ KEKTH’07 J/ψ D e- D*  e+ D • .

  44. Y(3940) hybrid? J. Brodzicka for Belle @ KEKTH’07 • B

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