new frontiers in qcd (qcd-2011) yonsei university, seoul korea, october 27 ~ 28, 2011 observation of...

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New Frontiers in QCD (QCD-2011) Yonsei University, Seoul Korea, October 27 ~ 28, 2011 Observation of charged bottomonium-like states -and a few other items- Stephen Lars Olsen Seoul National University

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New Frontiers in QCD (QCD-2011)Yonsei University, Seoul Korea, October 27 ~ 28, 2011

Observation of charged bottomonium-like states-and a few other items-Stephen Lars OlsenSeoul National UniversityConstituent Quark Model2

= (uds)

Mesons are quark-antiquark pairsBaryons are quark-quark-quark thripletsFabulously successfulQuarks are probably the mostwell known particle physics quantityamong the general public Are there other color-singlet spectroscopies?Pentaquark:H-diBaryon



qq-gluon hybrid mesons


ccudusdOther possible white combinations of quarks & gluons:____udusds__ucuc___pD0D*0_S=+1 Baryontightly bound6-quark stateColor-singlet multi-gluon bound statetightly bounddiquark-diantiquarkloosely boundmeson-antimesonmolecule


Strategy:Search for a meson that decays to a final state containing a c and c quark, If it is a standardqq meson, it has to occupy one of the unfilledstates indicated above. If not, it is exotic.__unassignedcc production at B factories

XYZ mesons

Zb(10610) 10608 2 15 3 1+ phb(1,2P),pY(1,2,3S) Y5Sp Zb(10610) Zb(10610) 10653 2 14 3 1+ phb(1,2P),pY(1,2,3S) Y5Sp Zb(10650) The X(3872)

????Study p+p-J/y produced in BK p+p- J/y decaysEB=Ecm/2Polarized along flightdirection in B rest frameThe X(3872) in BK p+p-J/y discovered by Belle (140/fb)

M(ppJ/y) M(J/y)yp+p-J/yX(3872)p+p-J/yPRL 91, 262001 (2003)X(3872)p+p-J/y with all Belle data


3-dimensional fitsM(J/+-) MBEB-Ecm/2diquark-diantiquark? Predict : DM(Mx(B+)-Mx(B0)) =83 MeV Maiani e al PRD71, 014028diquark-diantiquark (tetra-quark) modelucucdcdcXu=Xd=

Expect two neutral states:Plus charged partners:dcucucdcX+=X-=

Isospin relations:Two neutral states?


Predict : DM(Mx(B+)-Mx(B0)) =83 MeV Maiani e al PRD71, 014028

charged partners of the X(3872) ? X+(3872)p+p0J/y : Isospin triplet? B0X+K-B+X+K0Nevts =4.27.8B(B0K-X+)xB(X+p+p0J/y)1exptl upper limit: nr=1pinnedto:Mcc2=3930 MeVT.Barnes et al PRD 72, 054026

X(3872) g y ??Belle 2010:no signals!! B(B+K+ X3872)xB(X3872gy) B(B+K+ X3872)xB(X3872gJ/y)

< 2.1 (90%) B+B0B0B+yJ/yp+p-y l+l-

M(gy) M(gy) 2-+ cc assignment? hc2 huge for Isospin-violating decayc.f.: G(yp0J/y)0.4 keVG(hc2 gy) ~0.4 keVG(hc2 g J/y) ~9 keV

G(hc2 gy)/G(hc2 g J/y) 0.20 GeV29.43 GeV