X(3872), Y(3915) & Charged Zc states Stephen Lars Olsen Seoul National University New Hadron Spectroscopies/Dynamics WS Haeundae, Busan Nov. 19, 2012

charmonium (cc) meson spectra _ Charmonium All of the states below 2mD have been assigned Many radiative transitions have been measured with widths that agree with theory A number of hadronic transitions (y’ppJ/y; hJ/y; p0J/y; p0hc) have been measured, also with widths that agree with theory Above 2mD a number of states have been found that have defied assignment to a charmonium level & most have anomalously large hadronic transition widths e.g.; G(y’hJ/y) ≈ 10keV; G(y3ShJ/y) ≈ 1MeV G(y’p+p-J/y)≈100keV; G(Y4260)p+p-J/y) > 1MeV

bottomonium x102 p+p- agree with theory (MeV) p+p- p+p- p+p- p+p-

The X(3872)

Latest result on the X(3872) CMS at HCP2012 (Kyoto) last week X(3872) production very similar to y’ production  X(3827) has a significant cc component _

M(p+p-) for X(3872)p+p-J/y rp+p- p+p- S-wave X3872 r p+ J/y p- E.A. Yetkin, parallel talk Hadron Collider Physics Symposium (Kyoto Nov. 2012)

What else we know about the X(3872) M(X3872) – (mD0 + MD*0 ) = (-120 ± 350) keV G(X3872) < 1.2 MeV JPC = 1++ likely, JPC= 2-+ still possible Bf(BKX3872) x Bf(X3872p+p- J/y) = (8.6 ± 0.8) x 10-6 Bf(X3872p+p- J/y) > 2.6% Bf(X3872D0D*0)/ Bf(X3872p+p- J/y) =9.3±2.7 Bf(X3872 g J/y) /Bf(X3872p+p- J/y) = 0.21±0.08 Bf(X3872 wJ/y) /Bf(X3872p+p- J/y) = 0.8±0.03 No Isospin partners are found  I=0 this means X3872p+p- J/y violates Ispin symm. _

1++ cc assignment? cc1 ‘ _ ‘ Mass is too low? Theory: Expt: pinned to: Mcc2=3930 MeV Mass is too low? 3872 vs 3905 MeV nr=2 splitting> nr=1 ‘ Theory: expt upper limit: <2.1 3872 MeV T.Barnes et al PRD 72, 054026 Expt: use theory: c.f.: G(y’p0J/y)≈0.4 keV

2-+ cc assignment? hc2? _ Mass is too high?: Expt: pinned to: My”=3770 MeV &My2=3823 MeV Mass is too high?: 3872 vs 3837 MeV Expt: use theory: c.f.: G(y’p0J/y)≈0.4 keV Y. Jiaet al arXiv:0107.4541 Theor: BKhc2 violates factorization BKhc not seen BKcc2 barely seen _ Theory: hc2  DD* expected to be tiny Belle & BaBar:: G(XDD*)/G(Xp+p-J/y)=9.5±3.1 Y. Kalasnikovaet al arXiv:1008.2895 hc2ghc(1S) & pphc modes expected to dominate _

If not cc, then what? _ D*0 q c c q s c c s D0 Possibilities that have been suggested: tightly bound diquark-diantiquark loosely bound meson-antimeson “molecule” _ q c _ c q __ D*0 In color space: _ s “nuclear” forces c _ p,s _ c red+blue=magenta (antigreen) cyan+yellow=green (antimagenta) s D0 A colored diquark is like a antiquark A colored diantiquark is like a quark This likes M(X3872) ≈ mD0+mD*0 & can explain large Ispin violation This requires existence of isospin (& octet) partner states, which are not seen.

X(3872)-J/y relative sizes drms(208Pb nucleus)≈5.5 fm + + + + X(3872) 208Pb + + + + drms(X3872) ~ 8 fm + + + + + + + + drms(J/y) ≈ 0.4 fm + + + J/y Volume(J/y) /Volume(X3872) ≈ 10-4 How can such a fragile object be produced in H.E. pp collisions? heavy ion collisions?? -- arXiv 0906.0882: sCDF(meas)>3.1±0.7nb vs stheory(molecule)<0.11nb C. Bignamini et al, PRL 103, 162001:

Is the X(3872) the cc1? ‘ _ ‘ M cc potential mass value Isospin Violation in X(3872) decay: _ 3905 DD* screening MD+ +MD*- 3880 X ≈on mass shell ≈8 MeV off mass shell MD0 +MD*0 3872 MX(3872) –(MD0 + MD*0) = -0.12 ± 0.35 MeV _ What pulls M down from 3905 MeV --past the D+D*- threshold— exactly to the D0D*0 threshold? MX(3872) –(MD+ + MD*-)= -7.74 ± 0.35 MeV _ _ Best guess: X3872 is a cc1 - DD*-molecule mixture, brought down in mass to mD0+mD*0 by some mechanism I don’t understand. ‘ c.f. B.-Q. Li & K.-T. Chao PRD 79, 094004

The Y(3915) aka X(3915)

Y(3915)wJ/y K w w B Y Y J/y J/y Belle gg  wJ/y B+K+ wJ/y Belle 2010 gg  wJ/y B+K+ wJ/y Belle 2005 M=3943 ± 17 MeV G= 87 ± 34 MeV M=3915 ± 5 MeV G= 17 ± 11 MeV M(wJ/y) M(wJ/y) gg  wJ/y BaBar 2008 B+K+ wJ/y BaBar 2012 M=3919± 3 MeV G= 13 ± 7 MeV B0K0 wJ/y M(wJ/y) M(wJ/y) M=3915 ± 5 MeV G= 34 ± 13 MeV

BaBar measurements favor JPC=0++ ql* n Beam axis ql* qln 0+ 2+ BaBar PRD 86, 072002 (2012) arXiv:1207.2651

What we know about the Y(3915) M(Y3915) = 3917 ± 3 MeV G(Y3915) = 21 ± 7 MeV Bf(BKY3915) x Bf(Y3915wJ/y) = (5.1 ± 1.0) x 10-5 G(Y3915gg) x Bf(Y3915wJ/y) = 54 ± 9 eV Bf(Y3915D0D*0) /Bf(Y3915wJ/y) < 1.3 JPC = 0++ likely Bf(Y3915DD) /Bf(Y3915wJ/y) < 1.3 G(Y3915wJ/y) ≈1MeV Published data _ _ My estimates (see backup slides)

Y(3915) = cc0 charmonium state? ‘ 23P0 cc state _ If Y(3915) = cc0: ‘ -G(cc0wJ/yc0) ≈ 1 MeV too wide for hadronic charmonium transitions c.f.: G(y’p+p-J/y)≈0.1 MeV - mass is to high: M(cc2)-M(cc0) ≈ 14 MeV ≈1/10th the n=1 splitting: M(cc2)-M(cc0)=141 MeV M=3929 ± 5 MeV ‘ ‘ - Y(3915)DD not seen? theory predicts: G(cc0DD) ≈ 30 MeV my estimate: G(Y(3915)DD) < 2 MeV _ ‘ _ _

Y(3915) & thresholds 3.95 D+D- s s Y(3915) M (GeV) 3.90 D+D*- D0D*0 3.85

arXiv:1101.2071 Gtot= 17MeV Only VV couplings (no DD coupling):

charged Zc charmonium-like states + u c d c Smoking guns for 4-quark states

BK p+ y’ & BKp+ cc1 M2(p+y’) M2(p+cc1) ??? M2(K+p-) M2(K+p-) ?? K*(890)K+p- K*(1400)’s K*(1680) K*(1430)K+p-? K3*(1780) R.Mizuk et al. (Belle) PRD 78, 072004 S.-K.Choi et al. (Belle) PRL100, 142001

fit with a 2-body isobar model Our default model ky’ K*(890)y’ K*(1410)y’ K0*(1430)y’ K2*(1430)y’ K*(1680)y’ KZ+ K*y’ B K2*y’ (cc1) Kpy’ (cc1) (cc1) KZ+ (cc1) Z+ p+ y’ (p+cc1) (cc1) with & without

BK p+ y’ results with no KZ+ term 2 1 1 2 3 4 5 R.Mizuk et al. (Belle) PRD 80, 031104 C B A 3 4 A B 5 C fit CL=0.1% 51

BK p+ y’ results with a KZ+ term 2 1 B 1 2 3 4 5 A 3 4 C B C A 5 fit CL=36% R.Mizuk et al. (Belle) PRD 80, 031104

BK p+ y’ Dalitz-plot fit results K* veto applied With Z(4430) Significance: 6.4s No big contradiction BaBar: no confirmation Without Z(4430) B. Aubert et al. (BaBar) PRD 79, 112001 Belle: = (3.2+1.8+9.6 )x10-5 0.9-1.6

Dalitz analysis of B0K-p+cc1 R.Mizuk et al. (Belle) PRD 78, 072004 DE GeV M2(p+cc1) ??? G K3*(1780) K*(890) K*(1680) K*(1400)’s M (J/yg) GeV

Fit model: all low-lying K*’s (no Z+ state) b c d g f e a b e f c d g C.L.=310-10 R.Mizuk et al. (Belle) PRD 78, 072004

Fit model: all K*’s + one Z+ state b c d g f e a b e f c d g C.L.=0.1% R.Mizuk et al. (Belle) PRD 78, 072004

Are there two? ? ? ? ? M2(p+cc1) a b c d M2(p+cc1) R.Mizuk et al. (Belle) PRD 78, 072004

Fit model: all K*’s + two Z+ states b c d g f e a b e f c d g C.L.=42% R.Mizuk et al. (Belle) PRD 78, 072004

Two Z-states give best fit Projection with K* veto R.Mizuk et al. (Belle) PRD 78, 072004 (2008)

BaBar doesn’t agree BaBar K* +Z1+Z2 K* only J. Lees et al. (BaBar) PRD 85, 052003 (2012) BaBar K* +Z1+Z2 K* only Conclusion: no >2s evidence for Z1 or Z2  p+ cc1, set upper limits:

Critique of the BaBar critique constr. interf BaBar Belle incoherent destructive interf J. Lees et al. (BaBar) PRD 85, 052003 (2012) R.Mizuk et al. (Belle) PRD 78, 072004 (2008)

Beautiful examples of charged bottomonium-like mesons in Roman Mizuk’s talk.

Summary Lots of new particles found recently low-lying charmonium/bottomonium states - cc2, yc2, hb(1P), hb(2P), hb(1S),hb(2S),cb(3P),… -all match potential model predictions well X(3872) seems to be the cc1, charmonium state with a large D0D*0 “molecular” component why is its mass right at the D0D*0 threshold? Y(3915)w J/y properties reproduced by a VV molecule-type model -JPC=0++, but Y(3915)DD not seen Clear examples of charged charmonium-like (& bottomonium-like) states are seen Z(4430)p+y’; Z1(4050) & Z2(4250)p+cc1 (in spite of what BaBar says!!) Lots of evidence for molecules as opposed to diquarks, etc… ‘ _ _ _ _ _

Lots of pieces Are they all from the same puzzle? Y(3940) Y(4140) X(3940) Are they all from the same puzzle? X(4160) Z1(4050) Y(4660) Z(4430) Y(4008) Z2(4250) Y(4260) Y(4360) X(3872)

Does Y(3915)  DD ? _ _ No signal near 3940: BKD0D0 BKy(3770) D0D0 J. Brodzicka et al. (Belle) PRD 100, 092001 BKy(3770) D0D0 68+15 events | <16 events No signal near 3940: 3915 MeV Use 16/68 & scale from PDG values: