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“Exotic” bottomonium states

“Exotic” bottomonium states. Alex Bondar BINP, Novosibirsk Belle Collaboration. (Hadrons from Quarks and Gluons, January 16, 2014, Hirschegg , Austria) . Constituent Quark Model. Gell-Mann.

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“Exotic” bottomonium states

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  1. “Exotic” bottomonium states Alex Bondar BINP, Novosibirsk Belle Collaboration (Hadrons from Quarks and Gluons, January 16, 2014, Hirschegg, Austria)

  2. Constituent Quark Model Gell-Mann The model was proposed independently by Gell-Mann and Zweig in 1964 with three fundamental building blocks: 1960’s (p,n,L) Þ 1970’s (u,d,s): mesons are bound states of a of quark and anti-quark: Zweig baryons are bound state of 3 quarks:

  3. What about other color-singlet combinations? Pentaquark: H-diBaryon Glueball Tetraquark mesons qq-gluon hybrid mesons Other possible “white” combinations of quarks & gluons: u d u d s _ u tightly bound 6-quark state S=+1 Baryon d s u s d Color-singlet multi- gluon bound state D0 _ c _ u loosely bound meson-antimeson “molecule” c tightly bound diquark-diantiquark u _ p _ u c _ _ u _ D*0 c _ _ c c

  4. e+e-hadronic cross-section BaBar PRL 102, 012001 (2009) (1S) (5S) (6S) (4S) (2S) (3S) (4S) Belle took data at E=108671MэВ 2M(B) 2M(Bs) _ e+ e- ->(4S) -> BB,whereBisB+orB0 _ _ _ _ _ e+ e- -> bb ((5S)) ->B(*)B(*), B(*)B(*)p, BBpp, Bs(*)Bs(*), (1S)pp, X … main motivation for taking data at (5S)

  5. Puzzles of (5S) decays Anomalous production of (nS)+- with 21.7 fb-1 PRD82,091106R(2010) (MeV) PRL100,112001(2008) 102 Rescattering(5S)BB(nS) (2) Exotic resonance Yb near (5S) Simonov JETP Lett 87,147(2008) analogue of Y(4260) resonancewith anomalous (J/+-) Rb Dedicated energy scan  shapes of Rb and () different (2) (5S) is very interesting and not yet understood Finally Belle recorded 121.4fb-1 data set at (5S)

  6. e+e- -> hcp+p- by CLEO Observation of e+e- → +- hc by CLEO PRL 107,041803 (2011) Ryan Mitchell @ CHARM2010 Energy dependence of the cross section Enhancement of (hc+-)@ Y(4260) (hb +-) is enhanced @ Yb?  Belle search for hb in (5S) data

  7. Observation of hb(1P,2P) - - -- JPC = 0+ 1 1 + e+e-(5S)  hb(nP) +– reconstructed, use Mmiss(+-) (Pe+e- – P+-)2 (11020) 11.00 (10860) PRL108,032001(2012) +- 10.75 raw distribution (4S) 2M(B) hb(2P) 10.50 (3S) b(3S) residuals b(2P) hb(1P) hb(2P) 10.25 (2S) b(2S) b(1P) 10.00 hb(1P) MHF(1P) 9.75 Belle PRL 109. 232002 (2012) consistent with zero, as expected MHF(1P) = +0.8  1.1 MeV MHF(2P) = +0.5  1.2 MeV (1S) 9.50 b(1S) (0,1,2)++ Large hb(1,2P) production rates c.f. CLEO/BESIII e+e- hc +-

  8. Observation of hb(1P,2P) - - -- JPC = 0+ 1 1 + e+e-(5S)  hb(nP) +– reconstructed, use Mmiss(+-) (Pe+e- – P+-)2 (11020) 11.00 (10860) PRL108,032001(2012) +- 10.75 raw distribution (4S) 2M(B) hb(2P) 10.50 (3S) b(3S) residuals b(2P) hb(1P) hb(2P) 10.25 19% (2S) b(2S) b(1P) 10.00 hb(1P) 13%  9.75 41% Belle PRL 109. 232002 (2012) consistent with zero, as expected MHF(1P) = +0.8  1.1 MeV MHF(2P) = +0.5  1.2 MeV (1S) 9.50 b(1S) (0,1,2)++ Large hb(1,2P) production rates c.f. CLEO/BESIII e+e- hc +- hb(nP) decays are a source of b(mS)

  9. e+e-(5S)hb(nP) +–  b(1S)  (11020) 11.00 (10860) +- 10.75 (4S) 2M(B) 10.50 (3S) b(3S) b(2P) hb(2P) 10.25 (2S) b(2S) b(1P) 10.00 hb(1P) Observation of hb(1P,2P) b(1S)  9.75 Mmiss (+-) (n) (1S) 9.50 b(1S) - - First measurement  = 10.8 +4.0+4.5 MeV -- JPC = 0+ –3.7 –2.0 (0,1,2)++ 1 1 + reconstruct MHF(1S) Belle : 57.9  2.3 MeV 3 arxiv:1205.6351 PDG’12 :69.3  2.8 MeV hb(1P) b(1S) BaBar (3S) BaBar (2S) hb(2P) CLEO (3S) b(1S) pNRQCD LQCD   Kniehl et al, PRL92,242001(2004) Meinel, PRD82,114502(2010) MHF(1S) Mizuk et al. Belle PRL 109 (2012) 232002 Belle result decreases tension with theory as expected

  10. e+e-(5S)hb(nP) +–  b(1S)  Observation of hb(1P,2P) b(1S)  Mmiss (+-) (n) First measurement  = 10.8 +4.0+4.5 MeV –3.7 –2.0 PRL101, 071801 (2008) reconstruct MHF(1S) BaBar (3S)b(1S) Belle : 57.9  2.3 MeV 3 ISR arxiv:1205.6351 PDG’12 :69.3  2.8 MeV b(1S) hb(1P) b(1S) BaBar (3S) b(1P) BaBar (2S) PRL103, 161801 (2009) BaBar (2S)b(1S) hb(2P) CLEO (3S) b(1S) ISR b(1S) pNRQCD LQCD Kniehl et al, PRL92,242001(2004) Meinel, PRD82,114502(2010) PRD81, 031104 (2010) Mizuk et al. Belle PRL 109 (2012) 232002 Belle result decreases tension with theory CLEO (3S) as expected

  11. e+e-(5S)hb(2P) +–  b(2S)  First evidence for b(2S) Mmiss (+-) (2) Mizuk et al. Belle PRL 109 (2012) 232002 MHF(2S) = 24.3 +4.0MeV –4.5 First measurement arxiv:1205.6351 PRL LQCD pNRQCD b(2S) Belle 4.2w/ syst In agreement with theory (2S) = 4  8 MeV, < 24MeV @ 90% C.L. expect 4MeV Branching fractions Expectations BF[hb(1P)  b(1S) ] = 49.25.7+5.6 % BF[hb(2P)  b(1S) ] = 22.33.8+3.1 % BF[hb(2P)  b(2S) ] = 47.510.5+6.8 % 41% 13% 19% –3.3 Godfrey Rosner PRD66,014012(2002) –3.3 –7.7 c.f. BESIII BF[hc(1P)  c(1S) ] = 54.38.5 % 39%

  12. _ Anomalies in (5S)(bb)+– transitions (11020) Belle: PRL100, 112001 (2008) 100 11.00 [(5S) (1,2,3S) +–]>> [(4,3,2S) (1S) +–] (10860) _ +– Rescattering of on-shell B(*)B(*) ? 260 10.75 (4S) 2M(B) 2 330 10.50 (3S) Mass, GeV/c2 hb(2P) 430 10.25 1 190 (2S) Belle: PRL108, 032001 (2012) b(2S) 10.00 hb(1P) 290 6 9.75 partial (keV) expect suppression QCD/mb (1S) 9.50 (5S)  hb(1,2P) +– are not suppressed b(1S) spin-flip Heavy Quark Symmetry JPC= 0-+1--1-+ hb production mechanism? Study resonant structure in hb(mP)+–

  13. Resonant substructure of (5S)  hb(1P)+- phase-space MC Fit function _ ~BB* threshold _ _ ~B*B* threshold P(hb) = P(5S) – P(+-)  M(hb+) = MM(-) measure (5S)hb yield in bins of MM() data PHSP combine PRL108,122001(2012) Results M1 = MeV/c2 Significance 1 = MeV a = 18 (16 w/ syst) M2 = MeV/c2 non-res. amplitude ~0 2 = MeV  = degree

  14. Resonant substructure of (5S)  hb(2P)+- phase-space MC data PHSP combine hb(1P)+- hb(2P)+- MeV/c2 PRL108,122001(2012) MeV MeV/c2 M1 = MeV/c2 c o n s i s t e n t Significance MeV 1 = MeV 6.7 (5.6 w/ syst) M2 = MeV/c2  = degree degree 2 = MeV

  15. Exclusive (5S) ->(nS) p+p- (5S) (nS)+- (n = 1,2,3) (nS)  +- (3S) (2S) (1S) reflections

  16. _ Resonant structure of (5S)→(bb)+– (5S) hb(1P)+- (5S) hb(2P)+- Two peaks are observed in all modes! no non-res. contribution phsp Belle: PRL108, 232001 (2012) phsp Zb(10610) and Zb(10650) should be multiquark states Dalitz plot analysis M[ hb(1P) π] M[ hb(2P) π] (5S) (2S)+- (5S) (1S)+- (5S) (3S)+- note different scales

  17. Summary of Zb parameters Average over 5 channels  M1 = 10607.22.0 MeV  1  = 18.42.4 MeV  M2 = 10652.21.5 MeV  2  = 11.5  2.2 MeV M1 – (MB+MB*) = + 2.6  2.1 MeV M2 – 2MB* = + 1.8  1.7 MeV Zb(10610) yield ~ Zb(10650) yield in every channel Relative phases: 0o for  and 180o for hb

  18. Heavy quark structure in Zb A.B.,A.Garmash,A.Milstein,R.Mizuk,M.Voloshin PRD84 054010 (arXiv:1105.4473) Wave func. at large distance – B(*)B* Explains • Why hb is unsuppressed relative to  • Relative phase ~0 for  and ~1800 for hb • Production rates of Zb(10610) and Zb(10650)are similar • Widths –”– • JP 1+ quantum numbers Predicts Other Possible Explanations • Coupled channel resonances (I.V.Danilkin et al, arXiv:1106.1552) • Cusp (D.Bugg Europhys.Lett.96 (2011),arXiv:1105.5492) • Tetraquark (M.Karliner, H.Lipkin, arXiv:0802.0649)

  19. (5S)→(2S)π+π–: JP Results (2S)π+πData Toy MC with various JP JP = 1+ JP = 1- JP = 2+ JP = 2-

  20. Belle PRELIMINARY

  21. Heavy quark structure in Zb A.B.,A.Garmash,A.Milstein,R.Mizuk,M.Voloshin PRD84 054010 (arXiv:1105.4473) Wave func. at large distance – B(*)B* Explains • Why hb is unsuppressed relative to  • Relative phase ~0 for  and ~1800 for hb • Production rates of Zb(10610) and Zb(10650)are similar • Widths –”– • JP 1+ quantum numbers • Dominant decays to B(*)B* Predicts

  22. (5S)→B*B(*)π: B Selection 2-body (5S) decays B*B* Data (B signal) BB* BB Data (B side bands) 3-body (5S) -> B(*)B(*)π decays & rad. return to (4S): P(B)<0.9 GeV/c

  23. (5S)→B*B(*)π: Data MC: B*Bπ Data BB*π B*B*π MC: B*B*π (shifted by 45MeV) Red histogram – right sign Bπ combinations; Hatched histogram – wrong sign Bπ combinations; Solid line – fit to right sign data. Belle PRELIMINARY Fit yields: N(BBπ) = 0.3 ± 14 N(BB*π) = 184 ± 19 (9.3σ) N(B*B*π) = 82 ± 11 (5.7σ)

  24. (5S)→B*B(*)π: Signal Region Zb(10610) BB*π B*B*π Zb(10650) 8 6.8 Zb(10610) + Zb(10650) Zb(10650) alone PhSp Zb(10610)+ PhSp PhSp Zb(10650)+ PhSp Zb(10610) + Zb(10650) + PhSp Belle PRELIMINARY points – right sign Bπ combinations (data); lines – fit to data with various models (times PHSP, convolved with resolution function = Gaussian with σ=6MeV). hatched histogram – background component B*B*π signal is well fit to just Zb(10650) signal alone BB*π data fits (almost) equally well to a sum of Zb(10610) and Zb(10650) or to a sum of Zb(10610) and non-resonant.

  25. (5S)→B*B(*)π: Results Branching fractions of (10680) decays (including neutral modes): BBp < 0.60% (90%CL) BB*p = 4.25 ± 0.44 ± 0.69% B*B*p = 2.12 ± 0.29 ± 0.36% Assuming Zb decays are saturated by the already observed (nS)π, hb(mP)π and B(*)B* channels, one can calculate complete table of relative branching fractions: Belle PRELIMINARY B(*)B* channels dominate Zb decays !

  26. Heavy quark structure in Zb A.B.,A.Garmash,A.Milstein,R.Mizuk,M.Voloshin PRD84 054010 (arXiv:1105.4473) Wave func. at large distance – B(*)B* Explains • Why hb is unsuppressed relative to  • Relative phase ~0 for  and ~1800 for hb • Production rates of Zb(10610) and Zb(10650)are similar • Widths –”– • JPC 1+- quantum numbers • Dominant decays to B(*)B* • Similar states in Charm Predicts

  27. Observation of Zc(3900) at BESIII

  28. Observation of Zc(3885) in e+e- -> p-(D*D)+

  29. Observation of Zc(4020) in e+e- -> hcp+p-

  30. Observation of Zc(4025) in e+e- -> p-(D*D*)+

  31. Bottomonium-like vsCharmonium-like states

  32. Heavy quark structure in Zb A.B.,A.Garmash,A.Milstein,R.Mizuk,M.Voloshin PRD84 054010 (arXiv:1105.4473) Wave func. at large distance – B(*)B* Explains • Why hb is unsuppressed relative to  • Relative phase ~0 for  and ~1800 for hb • Production rates of Zb(10610) and Zb(10650)are similar • Widths –”– • JPC 1+- quantum numbers • Dominant decays to B(*)B* • Similar states in Charm • More bottomonium-like states Predicts

  33. 12GeV M.Voloshin PRD84(2011) 031502 U(?S) 11.5GeV U(6S) h U(5S) r w g r r p w g B*B* w Up hbphbr Ur Ur hbp Uh hbw Uw hbh Uw g BB* g Ur Uw BB Wb1 Xb Wb2 Wb0 Zb 0-(1+) IG(JP) 1+(1+) 0+(0+) 1-(0+) 0+(1+) 1-(1+) 0+(2+) 1-(2+) 0-(1-)

  34. SuperKEKB Belle II e+ New IR New superconducting /permanent final focusing quads near theIP New beam pipe & bellows Replace short dipoles with longer ones (LER) e- Add / modify RF systems for higher beam current Low emittance positrons to inject Redesign the lattices of HER & LER to squeeze the emittance Positron source Damping ring Low emittance gun Low emittance electrons to inject New positron target / capture section TiN-coated beam pipe with antechambers To aim ×40 luminosity

  35. Summary The first exotic bottomonium-like Zb+states were discovered in decays to (1S)+, (2S)+, (3S)+,hb(1P)+,hb(2P)+ Spin parity of Zbsis 1+ Zbs mainly decay to BB* and B*B*final states Zb(10610) dominantly decays to BB*, but Zb(10650) to B*B* Decay fraction of Zb(10650) to BB* is currently not statistically significant, but at least less than to B*B* Phase space of Y(5S)->B(*)B*p is tiny, relative motion B(*)B*is small, which is favorable to the formation of the molecular type states Y(5S) [and possible Y(6S)] is ideal factory of molecular states In heavy quark limit we can expect more molecular-like states in vicinity of the BB, BB* and B*B*. To study the new states we need the energy up to 12GeV

  36. Back up slides

  37. Summary of the Zc states

  38. We enter the new region – Physics of Highly Excited Quarkonium or/and Chemistry of Heavy Flavor We can expect much more from Super B factory

  39. Variables definition φ ψ π2 π1 π2 μ2 μ2 π2 μ2 ϑhel ϑ Zb Zb (nS) e+ π1 e- (5S) Zb μ1 (nS) μ1 μ1

  40. The X(3872) in BK p+p-J/y discovered by Belle (140/fb) PRL 91, 262001 (2003) y’p+p-J/y X(3872)p+p-J/y M(ppJ/y) – M(J/y)

  41. First measurements (5S) 121.4 fb-1 (6S) 5 fb-1 Measurements of the (nS)p+p-, hbp+p- cross-section vs energy Zb’s cross-section Radiative and hadronic transitions 44

  42. Branching Fractions (nS)π+π- production cross section (corrected for the ISR) at sqrt(s) = 10.865 GeV: σ(e+e-→ (1S) π+π- = [2.27 ±0.12(stat.) ±0.09(syst.)] pb σ(e+e-→ (2S) π+π- = [4.07 ±0.16(stat.) ±0.45(syst.)] pb σ(e+e-→ (3S) π+π- = [1.46 ±0.09(stat.) ±0.16(syst.)] pb Fractions of individual sub-modes: Belle PRELIMINARY

  43. (11020) 11.00 (10860) 10.75 (4S) 2M(B) 10.50 (3S) b(3S) b(2P) hb(2P) 10.25 Mass, GeV/c2 (2S) b(2S) b(1P) 10.00 hb(1P) Large production rate: N b(2S)  0.2 N b1 factor 30 9.75 c.f.(’c(2S)) = 0.007 (’c1) “Signal” of exclusively reconstructed b(2S) BESIII arxiv:1205.5103 PRL (1S) 9.50 b(1S) (0,1,2)++ - - -- JPC = 0+ 1 1 + CLEO data Dobbs, Metreveli, Seth, Tomaradze, Xiao, PRL 109 (2012) 082001 _ e+e- (2S)  b(2S) , b(2S)  4,6,8,10 , K, p/p (26 channels) 4.6 Issues  Bg from final state radiation can mimic signale.g. (2S)  K+K- n(+-) FSR power law tail instead of exponential not discussed hadrons Large MHF(2S) CLEO48.72.7 MeV Belle  strong disagreement with theory 5σ 24.3 +4.0 MeV  agrees with theory –4.5 –4.5 Reported excess is unlikely to be the b(2S) signal

  44. (11020) 11.00 (10860) 10.75 (4S) 2M(B) 10.50 (3S) b(3S) b(2P) hb(2P) 10.25 Mass, GeV/c2 (2S) b(2S) b(1P) 10.00 hb(1P) Large production rate: N b(2S)  0.2 N b1 factor 30 9.75 c.f.(’c(2S)) = 0.007 (’c1) “Signal” of exclusively reconstructed b(2S) BESIII arxiv:1205.5103 PRL (1S) 9.50 b(1S) (0,1,2)++ - - -- JPC = 0+ 1 1 + CLEO data Dobbs, Metreveli, Seth, Tomaradze, Xiao, PRL 109 (2012) 082001 _ e+e- (2S)  b(2S) , b(2S)  4,6,8,10 , K, p/p (26 channels) 4.6 Issues  Bg from final state radiation can mimic signale.g. (2S)  K+K- n(+-) FSR power law tail instead of exponential not discussed hadrons Large MHF(2S) CLEO48.72.7 MeV Belle  strong disagreement with theory 5σ 24.3 +4.0 MeV  agrees with theory –4.5 –4.5 Reported excess is unlikely to be the b(2S) signal

  45. Tetraquark? Ying Cui, Xiao-lin Chen, Wei-Zhen Deng, Shi-Lin Zhu, High Energy Phys.Nucl.Phys.31:7-13, 2007 (hep-ph/0607226) M ~ 10.2 – 10.3 GeV M ~ 10.5 – 10.8 GeV Tao Guo, Lu Cao, Ming-Zhen Zhou, Hong Chen, (1106.2284) M ~ 9.4, 11 GeV M.Karliner, H.Lipkin, (0802.0649)

  46. Coupled channel resonance? I.V.Danilkin, V.D.Orlovsky, Yu.Simonov arXiv:1106.1552 No interaction between B(*)B* or  is needed to form resonance No other resonances predicted B(*)B* interaction switched on individual mass in every channel?

  47. Cusp? D.Bugg Europhys.Lett.96 (2011) (arXiv:1105.5492) Line-shape Amplitude Not a resonance

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