1 / 36

Spectroscopy session : Heavy Quarks & Leptons 2010 Oct 11 Laboratori Nazionali di Frascati

Spectroscopy Results from Belle. SooKyung Choi Gyeongsang National University. Spectroscopy session : Heavy Quarks & Leptons 2010 Oct 11 Laboratori Nazionali di Frascati. XYZ mesons (>5 s signif). Electrically neutral. Electrically charged. The X(3872).

ndana
Télécharger la présentation

Spectroscopy session : Heavy Quarks & Leptons 2010 Oct 11 Laboratori Nazionali di Frascati

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Spectroscopy Results from Belle SooKyungChoi GyeongsangNational University Spectroscopy session : Heavy Quarks & Leptons 2010 Oct 11 LaboratoriNazionalidiFrascati

  2. XYZ mesons (>5s signif) Electrically neutral Electrically charged

  3. The X(3872)

  4. The X(3872) in BK p+p-J/y discovered by Belle (140/fb) y’p+p-J/y X(3872)p+p-J/y M(ppJ/y) – M(J/y) seen in 4 experiments S.K. Choi , S.L.Olsen et al PRL 91, 262001

  5. X(3872) mass in p+p-J/ychannel only <MX>= 3871.46 ± 0.19 MeV Belle meas. new CDF meas. CDF PRL103,152001(2009) MD0 + MD*0. 2010 3871.78 ± 0.29 MeV/c2 Dm(deuteron) = -2.2 MeV m = -0.32 ± 0.35 MeV

  6. X(3872)p+p-J/y in Belle recent results arXiv:0809.1224 605 fb-1 (BaBar) : (2.7 ± 1.6 ±0.4) MeV diquark-diquark prediction: DM=8±3 MeV Maiani et al PRD71, 014028 (BaBar) 0.41 ± 0.24 ± 0.05 BABAR: PRD 77,111101 (2008) [413 fb-1]

  7. p+p- system in X(3872)p+p- J/y comes from rp+p- Belle CDF: PRL 98 132002 rp+p- lineshape M(p+p- ) M(p+p- ) p+ r p- X3872 J/y

  8. JPC of the X(3872) Angular distributions for BKX(3872)KrJ/y Partial Wave basis: 775 MeV X(3872)r J/y is right at threshold  neglect higher partial waves 3872 MeV 3097 MeV 1++: L: S-Wave D-wave S: 1 1,2 2-+: L: P-Wave F-wave S: 1,2 1,2 Only 1 amplitude: BLS=B01  1 free parameter: 2 amplitudes: BLS=B11 & B12  3 free parameters normalization normalization complex

  9. CDF results 1++ fits well with no adjustable parameters 2-+ looks like 1++ for All JPC values other than 1++ or 2-+are ruled out with high confidence CDF: PRL 98 132002 1++ no adj. params 2- +2 adj. params 1- - O++

  10. _ Possible 1++ cc assignment: cc1 ‘ set by: Mcc2=3930 MeV ‘ • Mass is too low? • 3872 vs 3905 MeV • G(cc1  gy’) ~180 keV • G(cc1  g J/y) ~14 keV • G(cc1  gy’)/G(cc1  g J/y)>>1 ‘ ‘ T.Barneset al PRD 72, 054026 • Gp+p- J/y=(3.4±1.2)GgJ/y ~45 keV huge for Isospin-violating decay c.f.: G(y’p0J/y)≈0.4 keV

  11. _ Possible 2-+ cc assignment: hc2 set by: My”=3770 MeV • Mass is too high?: • 3872 vs 3837 MeV • G(hc2  gy’) ~0.4 keV • G(hc2  g J/y) ~9 keV • G(hc2 gy’)/G(hc2  g J/y)<<1 Y. Jiaet al arXiv:0107.4541 • Gp+p- J/y=(3.4±1.2) GgJ/y ~30 keV • huge for Isospin-violating decay • c.f.: G(y’p0J/y)≈0.4 keV • BKhc2 violates factorization • BKhc not seen • BKcc2 barely seen • hc2  DD* expected to be tiny • Belle & BaBar:: • G(XDD*)/G(XppJ/y)=9.5±3.1 Y. Kalasnikovaet al arXiv:1008.2895 hc2ghc s& pphc modes expected to dominate

  12. X(3872)g J/y (y’) ?? BaBar 2009: PRL 102, 132001 3.6s 3.5s X3872gy’ X3872gJ/y bkg subtracted B(B+K+ X3872)xB(X3872gJ/y)=(2.8±0.8)x10-6 B(B+K+ X3872)xB(X3872gy‘)=(9.5±2.8)x10-6 B(B+K+ X3872)xB(X3872gy’) B(B+K+ X3872)xB(X3872gJ/y) =3.4 ± 1.4 X3872g/y’ > X3872gJ/y !!

  13. Belle (May 2010): B+  K+ g J/y 1st evidence for B+K+cc2 calibration reaction cc1gJ/y 3.6s cc2gj/y Bf(B+K+cc1)=(49±3)x10-5 Bf(B+K+cc2)=(1.11±0.37)x10-5 B(B+K+cc2) B(B+K+cc1) = 0.022 ±0.007 0 -+,1++,1 -- factorization suppression penalty V. Bhardwaj QWG 2010

  14. X(3872)g J/y (y’) ?? Belle 2010: X3872gy’ X3872gJ/y no signals!! 4.9s B(B+K+ X3872)xB(X3872gJ/y)=(1.8±0.5)x10-6 BaBar:(2.8±0.8)x10-6 B(B+K+ X3872)xB(X3872gy’)<3.4 x10-6 B(B+K+ X3872)xB(X3872gy’) B(B+K+ X3872)xB(X3872gJ/y) BaBar:(9.5±2.8)x10-6 <2.1 (90%) disagreement BaBar = 3.4 ± 1.4

  15. B  K w J/y (275M BB) Belle 2005: M(p+p-p0 )= mw±22MeV B(X3872wJ/y) B(X3872p+p-J/y) =1.0 ± 0.5 “Y(3940)” PRL 94, 182002 X(3872)”w” J/y not seen in DD*

  16. 2010: X3872w J/y by BaBar M(p+p-p0 )= mw+18MeV B+  K+ w J/y -40 BaBar PRD 82, 011001 Nevts =26.7±7.6 B0  K0 w J/y X(3872)”w” J/y ?? B(X3872wJ/y) B(X3872p+p-J/y) =0.8 ± 0.3 S-wave fit prob: 7.1%  1++ P-wave fit prob: 61.9%  2-+ 2-+ favored NB: this is equivalent to a ~1.5s effect

  17. 1++ -- SCORECARD -- 2-+(Copied from Steve Olsen’s slide) • Prospects: • Angular studies will ultimately work but only • with LHCb- &/or Belle II – type statistics • In the meantime Belle is revisiting X3pJ/y & • looking for Xpphc & gghc with all the data

  18. The X(3915) The Y(3940)

  19. Belle new peak in ggwJ/y PRL 101, 082001 undetected X l+ l- J/y p+ w p0 p- undetected M = 3915  3  2MeV G = 17  10  3 MeV N = 49  14  4 events Significance = 7.7 s

  20. Is X(3915) = cc2‘ or cc0’ ?  JPC not yet determined, but M = 3929±5±2 MeV Gtot = 29±10±2 MeV Nsig = 64 ± 18 evts GggB(wJ/y) = 61 ±17±8 eV (JP=0+) GggB(wJ/y) = 18 ±5±2 eV (JP=2+) PRL 96, 082003 For comparison: Z(3930): GggB(DD) = 180±50±30 eV If X(3915)=Z(3930)=cc2’  >~ 0.1 Huge for above-open-charm-threshold charmonium For both JP options, If Ggg ~1keV, G(wJ/y) ~ 1 MeV also too large to be Charmonium

  21. G(Y3940wJ/y) is large Assume: B(B+K+ Y3940) B(B+K+J/y)= (10.1+0.4) x10-4 B(Y3940wJ/y) 4% G(Y3940wJ/y) 1.1 MeV too large for charmonium? using Belle-BaBar average: B(B+K+ Y3940)xB(Y3940wJ/y) = (5.0±0.8)x10-5 and PDG average: Gtot(Y3940)= 40-13 MeV +18

  22. Is there a b-sector counterpart to the Y(4260)?

  23. The Y(4260) Y(4260): seen in e+e-  gISRp+p-J/y At a dip in s(e+e-) hadrons) BES, PRL 88, 101802 PRL95, 142001 4260 ~50 pb ~3nb (cf:.G(y”p+p- J/y)  50keV) G(Y4260p+p-J/y) > 1.6MeV @90% CL > 10 G(y’p+p-J/y) X.H. Mo et al, PL B640, 182 (2006)

  24. (4S)  (1S) p+p- 2S 3S 4S Belle: G((4S)p+p-(1S)) 477 fb-1 radiative return 52±10 evts

  25. Belle: G(5Sp+p-1S) 325±20 evts! 1/20th the data: 1/5th the cross-section But >6 times as many events 477 fb-1 23.6 fb-1 K.F. Chen et al (Belle) PRL 100, 112001 (2008)

  26. Partial Widths Assuming the source is the (5S) PDG value taken for (nS) properties N.B. Resonance cross section 0.302 ± 0.015 nb at 10.87 GeV PRD 98, 052001(2007) [Belle] >300 times bigger than that for the 4S!! Cf G (2S)  (1S)p+p- ~ 6 keV (3S) (1S)p+p- 0.9 keV (4S) (1S)p+p- 1.9 keV

  27. Are these events from the 5S? s(e+e- p+p-nS ) from a cm energy scan PDG(6S): m = 11019 ± 8 MeV G = 79 ±16 MeV 5S peak position Fitted parameters m = 10888.4 +2.7-2.6 ± 1.2 MeV/c2Γ = 30.7 +8.3-7.0± 3.1 MeV/c2 K.F. Chen et al (Belle) arXiv: 0810.3829 PDG(5S):

  28. Peak & width in p+p-(nS) different from (5S) e+e-p+p-(nS) Simplest interpretation: b-quark-sector equivalent to the c-quark-sector’s Y(4260) e+e- hadrons

  29. Summary • Belle results contradict the BaBar claim of a strong X3872gy’ decay width • Angular analyses of X3872p+p-J/y eliminate all JPC other than 1++ & 2 -+ • BaBar confirms the Belle Y3940 wJ/y threshold peak in B KwJ/y • & confirms Belle’s X3872wJ/y observation • X3872”w”J/y line shape favors 2-+ (but only by ~1.5s) • Peak at wJ/y in two photon process • Strong evidence for a Y4260-like state in the b-quark sector • huge decay width to p+p-(nS) Thank you

  30. Backup

  31. Y(4140) not significant at Belle Preliminary B→J/ψK with 772M BB Fit M(J/ψ) with Y(4140) parameters (from CDF’s 1st measurements) But lower effciency at J/ threshold B(B+K+ Y4140) B(YfJ/y) Belle < 6(7) x 10-6 at 90%CL CDF (1st ) (9.0±3.4±2.9)x10-6 No big Contradiction ! M(J/y)

  32. Charged resonancelike states Z+(4430) Z1+(4050) & Z2+ (4250)p+cc1

  33. M(p±y’ ) from BZ±(p± y’)K Veto Veto -13 -13 M2(py’) GeV2 K*(890)K+p- K2(0)*(1430)K+p- M2(Kp) GeV2 M(py’) GeV PRL 100, 142001(2008) BF(B0→K-Z+)xBF(Z+→y(2S)p+) = (4.1±1.0±1.4) x10-5

  34. Dalitz analysis confirms the existence of Z(4430)+ K* veto applied PRD 80, 031104(2009) Signif: 6.4s With Z(4430) Published results Without Z(4430) Mass & significance similar, width & errors are larger BaBar : Belle : BF(B0K- Z+) x BF(Z+y(2S)p+) Statistically No Big contradictions btn Belle & BaBar

  35. BaBar : no significant (4430)+ signal m = 4439 ± 8 MeV/c2Γ = 41 ± 33 MeV/c2 significance = 1.9 s PRL 79, 112001(2009) BaBar :

  36. M(p±cc1) from BK p±cc1 • No-Z resonance + known K*’s hypotheses in fit model give very poor fits • Two Z+ known K*’s structure is distinctive Z1 Z2 M(cc1p+) GeV/c2 for 1.0GeV2 < M2(K-p+) < 1.75GeV2 The Dalitz plot slice with most discrimination PRD 78, 072004(2008)

More Related