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Stephen Lars Olsen Seoul National University February 10, 2014

A New Spectroscopy of Hadrons. High-1 Gangwando. Stephen Lars Olsen Seoul National University February 10, 2014. Visions of hadrons. T h r o u g h a t h e o r i s t ‘ s m i n d. What is seen by an experimenter. multiquark states from diquarks & diantiquarks. red - blue diquark.

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Stephen Lars Olsen Seoul National University February 10, 2014

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  1. A New Spectroscopy of Hadrons • High-1 • Gangwando Stephen Lars Olsen Seoul National University February 10, 2014

  2. Visions of hadrons Throughatheorist‘s mind What is seen by an experimenter

  3. multiquark states from diquarks & diantiquarks red-bluediquark green-reddiquark blue-greendiquark d u d u d u  _  _ _ 3 3 3 u d s s s d u d s u s s magenta anti-triplet cyan anti-triplet yellow anti-triplet (anti-red) (anti-green) (anti-blue) H-dibaryon d u Pentaquark u d u c tetraquark meson _ u s _ _ u s s d d c d magenta-cyan-yellow color singlet 5-q state magenta-cyan-yellow color singlet 6-q state green-magenta color singlet 4-q state (anti-green) “exotic” hadrons that particle theorists love

  4. multiquark states from “molecules” _ _ D u d u d s d K c d L p s u p,s,w s,w p,s,r,w p,s,w u d d u _ u d _ _ u N c u s L p u D* _ _ _ Pentaquark H-dibaryon baryonium tetraquark meson “exotic” hadrons that nuclear theorists love

  5. _ Non-qq mesons or non-qqq baryonspredicted by `QCD-motivated’ models u d u d s _ u u s d s d Where are they?? glueballs H-dibaryon pentaquarks D0 _ _ c c u _ u _ c c u _ p c _ _ _ u D*0 c diquark-diantiquarks hybrids molecules non-qq & non-qqq color-singlet combinations _

  6. The XYZ quarkonium-like mesons

  7. Charmonium spectrum Any meson that decays to a c and c quark should fit in one of the (gray) unassigned states.

  8. XYZ charmoniumlike mesons 1++ Zc(3900)+ 3899 ± 6 46 ± 22 1+(-)Y(4260)p-(p+J/y) 0++ 0-+ 0+(+)/1—(+) 0-+ 0+(+)/1—(+) 1+(-)

  9. _ cc assignments for the XYZ mesons? no unassigned levels for the 1-- Y(4260) & Y(4360) the(4) charged Zs must have a minimal quark content of ccud _ _ theY(3915) mass and G(YwJ/y) are too high for the cc0(2P). Also, no sign of YDD theX(3940) & X(4160) as the hc(3S) & hc(4S) would imply huge hyperfine splittings for n=3&4 _ theX(3872) is a long complex story

  10. the Y(4260) found by BaBar in e+e- gISR+-J/ s(e+e- hadrons) BaBar PRD86, 051102 Ecm (GeV) M(+-J/) (GeV)

  11. Y(4260) +-J/ confirmed by Belle e+e-gISRp+p-J/y Belle PRL99, 182004 No sign of Y(4260)  D(*)D(*) Y(4260) peak in s(p+p-J/y) occurs at a dip in s(D(*)D(*)) M(+-J/) (GeV) e+e-hadrons G(p+p-J/y) is large, 10~100 × charmonium X. H. Mo et al., PLB 640, 182 BESII PRL88, 101802 Ecm (GeV)

  12. Is there a b-quark version of Y(4260)? ? p+p-ϒ(1S) e+e-hadrons B*B* e+e-p+p-ϒ(1S) e+e- hadrons BB BB* e+e-p+p-J/y e+e-p+p- J/y Ecm (GeV)

  13. “bottomonium” bb mesons _ ϒ(4S) 2MB = 10358.7 MeV Is there any anomaly in (4S,5S) p+p-  (1S) ? p+p-

  14. G(4S)p+p-(1S) G”(5S)”p+p-(1S) (4S)  (1S) p+p- 2S 3S 4S Belle: PRD 75 071103 Belle: PRL 100 112001 • 23.6 fb-1 477 fb-1 Lum ~1/20th σ ~1/5th Signal ~×6 325±20 evts 52±10 evts Signal “5S” 3S 2S 4S

  15. “(5S)” p+p-  (1S) ? Υ(3S)π+π- π+π- M2(ϒπ±) Υ(2S)π+π- M2(ϒπ±) Υ(1S)π+π- π+π- M2(ϒπ±) M2(π+π-)

  16. “(5S)” p+p-  (1S) ? Υ(3S)π+π- π+π- M2(ϒπ±) M(ϒ(3S)π±) Υ(2S)π+π- π+π- Υ(1S)π+π- M(ϒ(1S)π±)

  17. Belle PRL 108, 122001 (2012) + 121.4 fb-1 “(5S)” p-Zb1,2 p+(1,2,3S) p+ 10,660 MeV 10,610 MeV (3S) (2S) (1S) M((nS)π+)max

  18. JP of the Zb states

  19. JP of the Zb states Belle PRELIMINARY

  20. Summary of parameter measurements mB+mB* 2mB* B b d Zb(10610) Zb(10650) M=106082 MeV M=106532 MeV =18.42.4 MeV =11.52.2 MeV B* b d March 2012 Belle PRL 108, 122001

  21. _ _ B-B* & B*-B* molecules?? B Zb(106050)± Zb(106010)± B* b b b _ _ b _ _ B* B* _ _ B-B* “molecule” B*-B* “molecule” MZb(106010) –(MB+MB*) = + 3.6 ± 1.8 MeV MZb(106010) –2MB* = + 3.1 ± 1.8 MeV Slightly unbound threshold resonances?? M=10608.11.7 MeV M=10653.31.5 MeV Belle: =15.52.4 MeV =14.02.8 MeV MB* + MB* = 10650.2  1.0 MeV PDG: MB + MB* = 10604.50.6 MeV

  22. _ _ Zb(10610)BB* & Zb(10650)B*B* “(5S)” p-(BB*)+ “(5S)” p-(B*B*)+ _ _ Zb(106050)± Zb(106010)± M(B*B*) _ M(BB*) _ Belle arXiv:1209.6450 Bf(Zb(10610)BB* Bf(Zb(10610)p+(bb) _ Bf(Zb(10610)B*B* Bf(Zb(10610)p+(bb) =6.1±0.4 _ =2.8±0.4 _ _

  23. Are there c-quark versions of Zb’s Y(4260) discovered Is there a b-quark equivalent? Yes, & it decays to Zb states ??? Are there c-quark versions of Zb’s?

  24. run BEPCII/BESIII as a Y(4260) factory Typical J/ +- e+e- +-J/ @Ecm=4260 MeV J/ + Y4260 e+ e+ - Belle PRL99, 182004 e+e-gISRp+p-J/y BESIII: arXiv:1303.5949 (e+e- +-J/) = (62.91.93.7) pb

  25. Y(4260)p-Zc(3900)+p+J/y BESIII: PRL 110, 252001 p- Significance >8 p+ • Mass = (3899.0±3.6±4.9) MeV • Width = (46±10±20) MeV • Fraction = (21.5±3.3±7.5)%

  26. Zc(3900) confirmed by Belle Mass = (3894.5 ± 6.6 ± 4.5) MeV Width = (63 ± 24 ± 26) MeV Fraction = (29.0 ± 8.9)% (stat. err. only) Belle: PRL 110, 252002

  27. Y(4260)p-Zc(3900)+ D0 _ D*+  DD* _ Zc Y(4260) Significance >18 p- BESIII PRL 112, 022001 (last month) D0D*+ _ DD* _ D+D*0 _ • Mass = (3883.9 ±1.5 ±4.2) MeV • Width= (24.8 ±3.3 ±11.0) MeV • DD*/p+p-J/y = 6.2 ± 1.1 ± 2.7 _

  28. JP of the Zc(3900)? JPC=?? initial state: Zc q e+ e- 1;±1 final state: p- JPC=0- BESIII data JP=1- The data clearly establish JP=1+ JP=1+ JP=0-

  29. Are there others?

  30. Study Y(4260)p+p-hc decays ghc 16 channels sharp M(phc) peak but not near ~3900 MeV p+p- g M(p±hc) BESIII PRL 111, 242001 (2 months ago) hadrons

  31. Y(4260)p+Zc(4020)- p-hc no significant signal for Zc(3900)±p±hc p+ Zc(4020) p- BESIII PRL 111, 242001 M(p±hc) g 5.6 ± 2.8 MeV above D*0D*- thresh. = 4017.3 ±0.3 MeV Mass = (4022.9 ±0.8 ±2.7) MeV Width= (7.9 ±2.7 ±2.6) MeV fraction = 0.18 ± 0.07 Fit results: hadrons

  32. _ _ Does the Zc(4020)DD*? … D*D*? Zc(4020)D*D*? _ Zc(4020)DD*? _ 4023 MeV BESIII arXiv:1308.2760 4023 MeV BESIII PRL 112, 022001 D0D*+ _ D+D*0 _ _ M(D*D*) Something there (~10s!), but … • Mass = (4026.3 ± 2.6 ± 3.7) MeV • Width= (24.8 5 ± 5.6 ± 7.7) MeV Fit results: No sign of Zc(4020)DD* _ … higher mass (~1.5s) and width (~1.5s) than Zc(4020)phc signal

  33. Zb & Zc mesons --“smoking guns” for non-qq mesons-- _ Zb Zc u b u c • decay to (nS) (J/y)  must contain bb (cc) pair • electrically charged  must contain ud pair _ _ b d c d _ B0 b d b d b b B*+ B0-B*+ ? ? Mixture?

  34. molecules?

  35. CMS search for b-sector version of X(3872) CMS: PLB 727 (2013) 57 (MB + MB*)-MU(1S)= 1144MeV >> mw Relevant channel is ispin-conserving XbwU(1S) (MD0 + MD*0)-My(1S)= 776 MeV < mw

  36. Y(4260) X(3872)? BESIII arXiv:1310.4101 X(3872) X(3872) X(3872) is this from Y(4260) decays?

  37. Y(4260) X(3872)? …cont’d X(3872) All cm energies combined: 6.3s ~20 evt signal BESIII arXiv:1310.4101 Consistent with originating from the Y(4260)

  38. Summary • QCD-motivated spectroscopies most favored by theorists do not seem to exist • evidence for Pentaquarks has disappeared • H-dibaryon with mass near 2mL is excluded at stringent levels • Numerous non-qq mesons not specific to QCD have been found • - Baryonium in J/ygpp at BESII and BESIII ?? • - XYZ mesons containing cc and bb pairs • The JPC=1- - Y(4260) and “(5S)” have no compelling interpretation • - huge couplings to p+p-J/y (p+p-(nS))  not predicted in any model!! • - strong sources of charged Zc (Zb) states with M near mD(*)+mD* (mB(*)+mB*) • - evidence for a strong Y(4260)gX(3872) transition _ _ _ _

  39. Lots of pieces X(4160) Y(4274) Zb(10610) Zb(10650) Y(3915) X(4630) Zc(3900) Y(4140) X(3940) Are they all from the same puzzle? Z1(4050) X(4250) Y(4660) Z(4430) Y(4008) Z2(4250) Y(4260) Y(4360) X(3872)

  40. Back-up slides

  41. Event in the Belle Detector

  42. The “XYZ” mesons Zb1(10610) 10,607±2 18±2 1-p±ϒ(1,2,3S)/hb(1,2S); BB* `ϒ(5S)’p±Zb1 Zb2(10650) 10,653±2 12±2 1-p±ϒ(1,2,3S)/hb(1,2S);B*B* `ϒ(5S)’p±Zb2

  43. “Old” hadronspectrosopy 1964 The constituent quark-parton model was proposed independently by Gell-Mann and Zweig. 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: baryons are bound state of 3 quarks:

  44. QPM Superseded by QCD in the 1970s:observed particles are color singlets color + complementary color  white white 3 primary colors  blue-yellow green-magenta red-cyan Λ= (uds) Mesons are color-anticolorpairs Baryons are red-blue-green triplets 44

  45. QCD “diquarks” ? symmetric 6-tet antisymmetric anti 3-plet - d d d u u u + u d d u u d u u d d 6  _ =  3 + s d + s u d s u s u - - s s s u s d u s d s s s _ 3  3 = 3  6

  46. Visions of hadrons Throughatheorist‘s mind What is seen by an experimenter

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