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Quarkonium spectroscopy and new states from BaBar

Quarkonium spectroscopy and new states from BaBar. Lorenzo Vitale Università and INFN Trieste, ITALY on behalf of BaBar Coll. PEPII & BaBar: not only B physics. SVT: 97% efficiency – 20 m m z resol SVT+DCH: s (p t )/p t =0.13% ·p t +0.45% EMC: s (E)/E=2.32%·E -1/4 +1.85%.

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Quarkonium spectroscopy and new states from BaBar

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  1. Quarkonium spectroscopy and new states from BaBar Lorenzo Vitale Università and INFN Trieste, ITALY on behalf of BaBar Coll. Lorenzo Vitale

  2. PEPII & BaBar: not only B physics SVT: 97% efficiency – 20mm z resol SVT+DCH: s(pt)/pt=0.13%·pt+0.45% EMC: s(E)/E=2.32%·E-1/4+1.85% Asymmetric energy B-Factory & Detector were optimized for CP in B physics … Excellent tracking and vertexing Excellent particle identification Excellent γ, π0 detection Data: ~330 fb-1 recorded so far ~90% @ 10.58 GeV ϒ(4S) ~360 M BB pairs ~10% @ 10.54 GeV qq … but plenty of other topics can be investigated THIS TALK: QUARKONIUM 1m Lorenzo Vitale

  3. Heavy Quarkonia Spectra Rich spectroscopy. Predictions become more critical when states are above the threshold for open flavour production Bottomonium Charmonium Y(4260)? S/P? ϒ(4S) X(3872)? T.Barnes, S.Godfrey and E.S.Swanson Phys.Rev. D72 054026 (2005) Lorenzo Vitale

  4. Selected quarkonium topics in this talk: • Bottomonium results: • hadronic non-BB decays of ϒ(4S) • Charmonium results: • Results on new particles in B decays and ISR events: • X(3872) • Y(4260) Lorenzo Vitale

  5. Bottomonium Studies:hadronic non-BB decays of ϒ(4S) Lorenzo Vitale

  6. Hadronic non-BB decays of ϒ(4S) ϒ(4S)BB mostly, but not only. BF of O(10-4) are expected. Cleo reported only upper limits of that order. LP-05: Belle reports first evidence for ϒ(4S) +-ϒ(1S) B=(1.0±0.2±0.4)•10-4 with 386•106 (4S) hep-ex/0512034, still preliminary We have predictions for partial widths and dipion spectrum in ϒ(mS) +-ϒ(nS), mS nS QCD multipole expansion (Kuan-Yan, PRD24(1981),2874 and many others) But model fails to describe dipion spectrum at low mass in 3S  1S No clear explanation yet (Mixing and coupled channel effects are not accounted for in those models) Lorenzo Vitale

  7. BaBar:ϒ(4S) +-ϒ(nS) BaBar Analysis strategy search for ϒ(4S) +-ϒ(nS) with ϒ(nS)  l+l- Results on l+l-=+-, use e+e- as cross check (Bhabha bkg) 211fb-1 preliminary DATA 211fb-1 on peak: (230.0±2.5)•106(4S) decays 22fb-1 ~40MeV below (4S) as a control sample (no (4S) candidates found) Validations with ISR returns to 2S1S & 3SnS Lorenzo Vitale

  8. PRELIMINARY Results preliminary ϒ(4S)+-ϒ(1S) 10 signal significance BF=(0.90±0.15)·10-4 =1.8±0.4 keV ϒ(4S)+-ϒ(2S) First evidence @7.3 BF=(1.29±0.32)·10-4 =2.7±0.8 keV preliminary Dipion spectra compared with QCD multipole expansion: 4S1S compatible 4S2S incompatible (peak at low M+-) preliminary To be submitted to PRL Lorenzo Vitale

  9. Results onX(3872)History & TheoryNEWS from BaBar:2 recently published results 1 preliminary result Lorenzo Vitale

  10. Brief history: 2003 discovery (cc interpretation?) First observed by Bellein B± → K±(J/+-) • Mass just at D0D0* threshold • Narrow (<2.3 MeV at 90%CL) • Compatible with J/0 • →IC=1+final state Then confirmed by CDF, D0and BaBar all in the same decay mode. Belle PRL 91 (2003) 262001 CDF PRL 93 (2004) 072001 D0 PRL 93 (2004) 162002 BaBar PRD 71 (2005) 071103 Ordinary charmonium interpretation in trouble. This width eliminates many possible assignments. This mass value and absence of c1 are in disagreement with potential model expectations for the 13D2 (JPC=2--) charmonium state Lorenzo Vitale

  11. Several Possible Interpretations of X(3872):cc, D0D*0 molecule, diquark-antidiquark, …? • Ordinary cc charmonium state T. Barnes and S. Godfrey, PRD 69 (2004) 054008 E.J. Eichten, K. Lane and C. Quigg, PRD 69 (2004) 094019 (aka Cornell potential model) • S-wave D0D*0 molecule N.A. Tornqvist, PLB 590 (2004) 209 M.B. Voloshin, PLB 579, 316 C.Y. Wong, PRC 69 (2004) 055202 E. Braaten and M. Kusunoki, PRD 69 (2004) 074005, 71(2005) 074005 E.S. Swanson, PLB 588 (2004) 189 • Dominant 1++ (2P) cc component + D0D*0/D0D*0continuum component C. Meng, Y.J. Gao and K.T. Chao, hep-ph/0506222 M. Suzuki, PRD 72 (2005) (mainly charmonium + channel coupling to DD*) • S-wave diquark-antidiquark bound state cucu L. Maiani, F. Piccinini, A.D. Polosa and V. Riquer, PRD 71(2005)014028 • Hybrid ccg B.A. Li, PLB 605 (2005) 306 • Vector glueball gg + a small mixture of cc K.K. Seth, hep-ph/0411122 • S-wave threshold enhancement in D0D*0 scattering D.V. Bugg, PRD 71 (2005) 016006 Lorenzo Vitale

  12. Several experimental studies: other decay modes, production mechanism, “partners”, … • BaBar PRL 93 (2004) 041801 no signal for X(3872)  J/  • BaBar PRD 71 (2005) 031501 no signals for isovector charged partners of X(3872) rate should be twice, isovector hypothesis ruled out @ 10–4 level IX=0 large isospin violation in J/+- decay • BaBar PRD 71 (2005) 051501 no evidence in ISR production JPC=1-- excluded • Cleo PRL 94 (2005) 032004 no evidence in  fusion and rad. production  JPC0-+, 0++, 2++ • Belle Preliminary Moriond QCD 06 (also LP05) ~5 evidence of B K D0D*0 (2++ is not favored) • Belle hep-ex/0505037 hep-ex/0505038 ~4 evidence of X(3872)J/ and X(3872)J/ sub- threshold both suggest C=+1  JPC=1++ favored from angular analysis (against 0++, 0-+) Lorenzo Vitale

  13. X(3872) J/+- with increased statistics in B0 and B+ decays at BaBar B±→X(3872)K± B0→X(3872)Ks PRD 73 (2006) 011101 61.2±15.3 6.1σ 8.3±4.5 2.5σ 211 fb-1 M=3871.3±0.6±0.1 MeV/c2 M=3868.6±1.2±0.2 MeV/c2 R = BF(B0→X(3872)Ks)=0.50±0.30±0.05 ΔM=2.7±1.3±0.2 MeV/c2 BF(B±→X(3872)K±) R & ΔM can be compared with model predictions R: some molecule model predicts R~0.1 (excluded?) ΔM: ~7±2 MeV/c2 in qqqq modelStatistics still low Lorenzo Vitale

  14. Search for radiative decays of X(3872) Preliminary X(3872)→J/ in B± → K±X signal extraction validated looking at B+c1K+ 260 fb-1 Implies C=+1 Preliminary results: 19.2 ± 5.7 events BF(B+X(3872) K+)(X(3872)J/) = (3.4±1.0±0.3) x 10-6 R = BF(X(3872) J/) = 0.34±0.14 BF(X(3872) J/+-) Confirms 4σ Belle signal with consistent BF & R hep-ex/050537 (2005) Lorenzo Vitale

  15. Inclusive Search for B±K±X(3872) PRL 96 (2006) 052002 • Novel technique variant of recoil technique: •  one B is fully reconstructed • charged K momentum distribution in the recoil rest frame system shows peaks due to two body decays • Observation of X states independent of the decay mode • Allows absolute BF measurement • • Huge bkg due to K in recoil B decays e.g. B→ K  J/ • No signal: • BF(B→XK)< • 3.2 10-4 @90%CL • BF(XJ/+-)> 0.042 @90%CL 211fb-1 Observed signals are consistent with exclusive measurements Lorenzo Vitale

  16. Y(4260) Lorenzo Vitale

  17. BaBar Observation of Y(4260) in ISR Discovered last year in ISR events JPC=1--: e+e-ISR+-J/ J/+-, e+e- PRL 95 (2005) 142001 (2S) Y(4260) 233 fb-1 12523events 8  Significance Confirmed by CLEO in energy scan (also in 00J/ mode) hep-ex/0602034 from J/ sideband Lorenzo Vitale

  18. Y(4260):Hadronic/dimuon cross section Y(4260) is not observed in the total e+e-hadrons cross section (a dip!), indicating that (Ye+e-) is much smaller than corresponding partial width of all known JPC=1-- charmonium resonances, while (Y+-J/) is much larger. Y(4260) R √s (GeV) Also here there are several interpretations alternative to conventional charmonium. It is important to search for the Y(4260) in other decay modes …. Lorenzo Vitale

  19. No Indication for Y(4260) in Other ISR-produced Final States (3770) DD(3900) (4040) (4160) Shaded: D sidebands M(K+K-) (4415) Y(4260) Shaded:  sidebands BABAR: 232 fb-1 PRD 73, 012005 (2006) BABAR: 232 fb-1 To be subm.to PRD BABAR: 289 fb-1 To be subm.to PRL preliminary preliminary Lorenzo Vitale

  20. Indication of Y(4260) in B decays PRD 73, 011101 (2006) 211 fb-1 3.1σ significance, assuming mass and width from ISR analysis; needs confirmation BF(B±Y(4260) K±, Y(4260) +-J/= (2.0±0.7±0.2) 10-5 Lorenzo Vitale

  21. Summary New/First measurements of non-BB hadronic decays of the ϒ(4S)  +-ϒ(nS) Partial widths compatible with expectations Dipion spectrum in 4S2S incompatible with QCD multipole expansion Found several states above the threshold for open flavour production showing unusual properties for an ordinary charmonium state: X(3872) I=0, JPC=1++ narrow state, produced in B decays and observed in several decay modes Y(4260) I=0, JPC=1-- broad state, produced in ISR events (and some indication in B decays), no DD decays seen FURTHER INVESTIGATION IS NEEDED TO UNDERSTAND THE NATURE OF THESE STATES Lorenzo Vitale

  22. Backup slides Lorenzo Vitale

  23. Known Heavy Quarkonia Spectra Rich spectroscopy with predictions that became more critical when states are close to the threshold for open bottom or charm production Lorenzo Vitale

  24. Charmonium production @ B-factories C=+1 C=-1 ISR production can give useful complementary information (even no signal) Lorenzo Vitale

  25. Mass of X(3872) Mavg = 3871.90.6 MeV/c2 , <2.3 MeV/c2 (90% CL) D0D*0=3871.31.0 MeV/c2 D+D*+=3878.6  1.0 MeV/c2 Lorenzo Vitale

  26. no signals for charged partners of X(3872) • no signal for X(3872)  J/  • no evidence in  fusion and radiative production at • CLEO 234M BB PRD 71 (2005) 031501 90M BB PRL 93 (2004) 041801 PRL 94 (2005) 032004 Lorenzo Vitale

  27. Evidence of X(3872)J/ Evidence for sub-threshold decay X(3872)J/ hep-ex/0505037 275M BB X(3872) 275M BB M(+-0) (GeV/c2) MJ/ (GeV/c2) • 10.63.6 events • 4.3  • 13.6 4.4 events • stat. sig.: 4.0  hep-ex/0505037 The evidence of the two decay modes suggests the C parity of X(3872) be +1 Lorenzo Vitale

  28. Properties of the X(3872):search for D0D00 decay mode N=12.5±3.9 (>5) • Select B(D0D00)K events • An excess M(D0D00) ~ MX is seen Rule out 2++ (strong D-wave suppression) Preliminary Br(XDD)/Br(X→ p+p-J/y) =12±5 Lorenzo Vitale

  29. BaBar Observation of Y(4260) in ISR • ISR events with K+K-J/ spectrum show a featureless mass spectrum  exclude the possibility of K and  misidentification. • ISR events with a nJ/ with additional pions show no structure that could feed down to produce Y(4260) in +-J/ mass spectrum. • Y(4260) not from two-photon events • no substantial improvement obtained by including (4040), (4160) or (4415) in the fits • A single relativistic BW(multiplied by PS factor and convoluted with Cauchy resolution function) + 2nd order polynomial are used in the fit. • if the observed signal is due to two interfering resonances 1st resonance: M  4260 MeV/c2,   50 MeV 2nd resonance: M  4330 MeV/c2,  narrow Signify the presence of 1-- state containing hidden charm. Lorenzo Vitale

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