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“Exotic” bottomonium states

This article explores the various color-singlet combinations of quarks and gluons, including pentaquarks, H-diBaryons, glueballs, and tetraquark mesons. It also discusses the puzzles of decays of the exotic resonance Yb near the Υ(5S) state and the observation of hb(1P,2P) decays. Measurements of the hb(1S) and hb(2S) masses are also presented.

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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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