Sookyung Choi Gyeongsang National University Physics in Collision, IHEP, Beijing, Sep 4-7, 2013 Hadron and Quarkonium Exotica 1

multiquark states from diquarks & diantiquarks magenta anti-triplet  _ 3  _ 3 _ 3 yellow anti-triplet cyan anti-triplet d dd d d u u u u u u s s s s ss u s d d u s d H-dibaryon (anti-green)(anti-blue) (anti-red) red-blue diquark green-red diquarkblue-green diquark u u d d s Pentaquark _ u c c d tetraquark meson _ _ magenta-cyan-yellow color singlet 6-q state magenta-cyan-yellow color singlet 5-q state green-magenta color singlet 4-q state (anti-green) 2

multiquark states from “molecules” H-dibaryon u u d d s Pentaquark _ c u c d  _ _ D D*  u s d u s d tetraquark meson -new dimensions to Nuclear Physics-   N K baryonium u u d u u d  p p _ _ _ _ _ 3

Non-qq mesons or non-qqq baryons predicted by `QCD-motivated’ models u c u c cc u d u s d _ _ _ _ u d u s d s _ u c u c _ _ _  D0D0 D* 0 _ pentaquarks glueballsH-dibaryon diquark-diantiquarkshybrids molecules _ Where are they ?? non-qq & non-qqq color-singlet combinations _ 4

 Pentaquark  H-Dibaryon  Baryonium  Doubly charged state 5

No Pentaquarks CLAS-2003 “observation” JLab CLAS PRL 96, PRL 91, J-PARC E PRL 109,

H dibaryon R.L. Jaffee, PRL 38, 195 (1977): J P = 0 + di-hyperon with M H ≈ 2m   − 80 MeV Tightly bound diquark triplet    s u d u s d u d s d s u Hyperon-hyperon molecular state or 7

models predict M H ≈2m  long-lived c  > 3 cm!! LQCD m  2m  (2.23GeV) (2.06GeV) 8

Recent Lattice QCD calculations M H = 2m  – 16.1 ± 2.1 ± 4.6 MeV M H = 2m  – “(30~40) MeV” S.R. Beane et al (NPLQCD) PRL 106, (2011) T. Inoue et al (NPLQCD) PRL 106, (2011) 9

Production via gluons in  (1S) decays Need to: produce 6 quark-antiquark pairs (including two ss quark pairs) very close in phase space  Is this likely???  u u d d ss X u s d u s d _ _ _ u s d u d s _ _ _ H 10

Anti-deuteron production in  (1S) decays  Similar process!!  p n ARGUS & CLEO expts:  (1,2S)  D + anything is large Bf(  (1,2S)  D X) ≈ 3 x Belle data samples: 100×10 6  (1S) decays + 160×10 6  (2S) decays _ _ H. Albrecht et al (ARGUS) PRB 236, 102 (1990) D.M. Asner et al (CLEO) PRD 75, (2007) D u u d u u d d d u d d u _ _ _ _ _ _ X 11

 (1,2S)   p  - X &  (1,2S)   X M(  p  - )-2m  M(  )-2m  (≈1300  events) (≈1000  events) __ No sign of an H signal expected signals for Bf(   HX)=(1/20)×Bf(   dX) _ 12 Belle data samples: 100×10 6  (1S) decays + 160×10 6  (2S) decays

90% CL upper limits on  (1S,2S)  H X B.H. Kim et al (Belle) PRL 110, (2013) factor of ≈20 13

pp bound state in J/    pp? _ BESII years ago -- _ 14

2012, with 5x more data PR L 108, (2012) Partial Wave Analysis: -J PC = 0 -+ >6.8 σ better than other assignments - I=0 FSI improves the fit quality by ~7   - M= ± 19 model MeV ( ≈2m p -40 MeV) -  < 76 MeV - Bf(J/    X)×Bf(X  pp)= ( ± 2.3 model )×10 -5  suggests Bf(X  pp)~large J/    pp _ _ _ 15

A pp bound state (baryonium)? p npp deuteron: loosely bound 3-q 3-q color singlets with M d = 2m p -  baryonium: loosely bound 3-q 3-q color singlets with M b = 2m p -  ? attractive nuclear force attractive force? There are lots & lots of models about this possibility 16 u u d u u d  p p _ _ _ _

Expectation for pp bound state m p +m p Above threshold X  pp ~100% below-threshold p and p annihilate to mesons I=0, J PC =0 -+ init. state: pp       ’ and 3(     ) are common _ _ _ _ 17

J/    X(1835)   (      ’ )? 2m p BESIII PR L 106, (2011) M=1837 MeV  190 MeV consistent with 0 -+ M(      ’)   3(     )? M(3(     )) 2m p M=1842 MeV  83 MeV BESIII: J/    3(     ) BESIII: J/        ’ ) BESIII arXiv: M=1842.2± MeV -2.6  =83 ± 14.2 ± 11MeV 18

Are the pp,      ’ & 3(     ) peaks all from the same state? channelM (Mev)  (MeV) J PC Bf(J/    X)xBf(X  f i) pp ( )x10 -4 ’’ (?)(2.9±0.1)x (     ) ±17? ?+ (0.24±0.08)x _ Need: J PC measurement for the X(1842)  3(     ) signal better measurements of widths & line shapes other decay modes Some of this will be done soon with BESIII’s 1.2B J/  event data sample, _ 19

Charmed Meson Spectrum Puzzle 20 DsDs DsDs D s0 D s1 c q _ c s _ * (2317) (2458) The D s & D s * masses are heavier than the D & D* masses, consistent with m s -m q ~100MeV. Why aren’t the D s0 (2317) and D s1 (2458) masses higher than their non-strange partners? c ~100MeV q s _ (2400) (2460)

21 D S0 + (2317) production predict: Some theorists (e.g. Terasaki, PTP 116, 435 (2006) ) interpret D sJ mesons as tetraquarks D s0 (2317) + D s0 (2317)  D s  + ++ D s0 (2317) + 0 Ispin 0+0+ 00 D0DD0D _ DDDD _ D s0 (2317)  Ds  + + predict: PDG: ( ) x10 -3 PDG: ( ) x10 -3 Search for Z ++ ( = D sJ ++ (2317))

Improved BF for B  D s0 D: D s0  K + K -  + weighted average PDG(B + ): ( )×10 -3 PDG(B 0 ): ( )×10 -3 Agrees with PDG avgs & improves on the errors Mbc (GeV) MD s  (GeV)  E (GeV) Belle Preliminary

Search for Z ++ in B +  D - Z ++ ; Z ++  D s0  + No indication of signal Factor of ~30 below predicted level < 0.28 x (90% CL) Mbc (GeV) MD s  (GeV)  E (GeV) Belle Preliminary BaBar search in e+e- annihilation For charged partner <1.7% (for neutral partner <1.3%) 23 +

The XYZ quarkonium-like mesons 24

Charmonium spectrum Any meson that decays to a c and c quark should fit in one of the (gray) unassigned states. 25 _

XYZ charmoniumlike mesons 1 +(-) Z c (3900) ± 6 46 ± (-) Y(4260)    (   J/  ) (+) /1 —(+) 26 Y(4260)   X(3872)

cc assignments for the XYZ mesons? _ Y(4260) Y(4360) no unassigned levels for the Y (4260) & Y (4360) X(3940) X(4160) the X (3940) & X (4160) as the  c (3S) &  c (4S) would imply huge hyperfine splittings for n=3&4 Z(4430) Z 2 (4250) Z(4050) Z c (3900) the (4) charged Zs must have a minimal quark content of ccud _ _ Y(3915) the Y (3915) mass and  (Y   J/  ) are too high for the  c0 (2P) X(3872) the X (3872) is a long complex story. Latest news observing Y(4260)   X(3872) !! see Shen Chengping’ talk Neutral XYZ states Charged Z states 27

Quantum numbers of the Z(4430) + Results from 4D fit arXiv: is favored over 0 - by 2.9  28 Z(4430) +   +  ’ in B   -  +  ’

the Y(4260)  (e + e -  hadrons) E cm (GeV) BaBar PRD86, M(  +  - J/  ) (GeV) found by BaBar in e + e -   ISR  +  - J/  29

Y(4260)   +  - J/  confirmed by Belle Belle PRL99, Y (4260) peak in  (     J/  ) occurs at a dip in  (D (*) D (*) )   (     J/  ) is large, 10~100 × charmonium e + e -   ISR     J/  No sign of Y (4260)  D (*) D (*) M(  +  - J/  ) (GeV) BESII PRL88, E cm (GeV) X. H. Mo et al., PLB 640, 182 e + e -  hadrons 30

Is there a b-quark version of Y(4260)? BB BB * B*B*B*B* e + e -  hadrons E cm (GeV) 31

Bottomonium spectrum M B = MeV established recently discovered still not discovered 32 Most of the states below “open bottom” threshold have been identified Belle: PRL109, h b (1,2P)  b (1,2S)

_ Is there any anomaly in  (4S,5S)       (1S) ? “bottomonium” bb mesons 2M B = MeV ϒ (4S) 33

  (4S)   +  -  (1S)  ”  (5S)”   +  -  (1S) 2S 3S 4S  (4S)   (1S)  +   477 fb -1 52±10 evts Belle: PRD Signal 23.6 fb -1 Belle: PRL ±20 evts parent N(  +  -  (1S))  (Y 4S   1S )  theory  (4S) 52 ± ± 0.35 keV1.47 ± 0.03 keV “  (5S)” 325 ± ± 110 keV <1.5 keV Lum ~1/20 th σ ~1/5 th Signal ~×6 “5S” 4S 3S 2S 34

“  (5S)”       (1S) ? Υ (1S)π + π - Υ (2S)π + π - Υ (3S)π + π - M2(π+π-)M2(π+π-) M2(ϒπ±)M2(ϒπ±) M2(ϒπ±)M2(ϒπ±) M2(ϒπ±)M2(ϒπ±) π+π-π+π- π+π-π+π- 35

“  (5S)”       (1S) ? M( ϒ (1S) π ± ) Υ (1S)π + π - Υ (2S)π + π - M2(ϒπ±)M2(ϒπ±) π+π-π+π- π+π-π+π- Υ (3S)π + π - M( ϒ (3S) π ± ) 36

“  (5S)”   - Z b1,2 +   +  (1,2,3S)   (3S)   (2S)   (1S) M(  (nS)π + ) max ++ 10,610 MeV 10,660 MeV Belle PRL 108, (2012) fb -1 37

Z b (10610) M=  2.0 MeV  =18.4  2.4 MeV Z b (10650) M=  1.5 MeV  =11.5  2.2 MeV Belle PRL 108, Summary of parameter measurements m B +m B* 2m B* March 2012 b d b d B B* 38

B-B* & B*-B* molecules?? B B* b b _ B-B* “molecule” B* b b _ B*-B* “molecule” _ _ __ Z b (10610) ± Z b (10650) ± M Z b (10610) –(M B +M B* ) = ± 2.1 MeV M Z b (10650) –2M B* = ± 1.8 MeV Slightly unbound threshold resonances?? M=  2.0 MeV  =18.4  2.4 MeV M=  1.5 MeV  =11.5  2.2 MeV PDG: M B + M B* =  0.6 MeV M B* + M B* =  1.0 MeV Belle: _ _ 39

Z b (10610)  BB* & Z b (10650)  B*B* __ Z b (10610) ± Z b (10650) ± M(B*B*) _ M(BB*) _ “  (5S)”   - (BB*) + _ “  (5S)”   - (B*B*) + _ Bf(Z b (10610)  BB*) Bf(Z b (10610)   + (bb)) _ _ =6.2±0.7 Bf(Z b (10650)  B*B*) Bf(Z b (10650)   + (bb)) _ _ =2.8± arXiv:

Are there c-quark versions of Z b ’s Is there a b-quark equivalent? Y(4260) discovered Yes, & it decays to Z b states Are there c-quark versions of Z b ’s? ??? 41

run BEPCII/BESIII as a Y(4260) factory Belle PRL99, BESIII: arXiv:  (e + e -   +  - J/  ) = (62.9  1.9  3.7) pb e + e -   ISR     J/   Typical J/    +  - e + e -   +  - J/ cm =4260 MeV Y4260 J/  ++ -- e+e+ e+e+ 42

Y(4260)   - Z c (3900) +   -  + J/   Mass = (3899.0±3.6±4.9) MeV  Width = (46±10±20) MeV  Fraction = (21.5±3.3±7.5)% Significance >8  ++ -- 43 BESIII: PRL 110, arXiv:

44  Mass = ( ± 6.6 ± 4.5) MeV  Width = (63 ± 24 ± 26) MeV  Fraction = (29.0 ± 8.9)% (stat. error only) Belle: PRL 110, arXiv: Confirmed with CLEOc data! M = 3885  5  1 MeV  = 34  12  4 MeV 81  20 events 6.1  CLEOc data at 4.17 GeV: Z c (3895) + by Belle Couples to cc Has electric charge At least 4-quarks

Observation of e + e -   +  - h c (1P)  (h c )=416  28 Lum=827/pb   = 41.0  2.8  7.4 pb  (h c )=357  25 Lum=544/pb   = 52.3  3.7  9.2 pb BESIII preliminary 45 Ecm=4.26 GeVEcm=4.36 GeV h c  c,  c  hadrons [16 exclusive decay modes added] Charm, Changzheng Yuan

46 ++ -- Z c (4020(5) + ? ? ++ e + e -   + Z c (4020) -   +  - h c (1P) Simultaneous fit to 4.26/4.36 GeV data: 6.4  M(Z c (4020)) =  1.0  2.5 MeV;  (Z c (4020)) = 5.7  3.4  1.1 MeV R = 16.2  4.1  0.7 % R = 16.6  5.2  0.8 % BESIII preliminary

Remove DD, DD*, D*D*, DsDs, … removed 47 BESIII Charm, Changzheng Yuan e + e -   - (D*D*) + + c.c. at BESIII _

e + e -   - Z c (4025) +   - (D*D*) + +c.c. 48 _

Fit to   recoil mass >10  Yields : 401  47 Z c (4025) events. M(Z c (4025)) =  2.6  3.7 MeV  (Z c (4025)) = 24.8  5.6  7.7 MeV 49 BESIII: , submitted to PRL e + e -   - Z c (4025) +   - (D*D*) + +c.c. _

50 Z c (4020)=Z c (4025)? M(4020) =  1.0  2.5 MeV M(4025) =  2.6  3.7 MeV  (4020) = 5.7  3.4  1.1 MeV  (4025) = 24.8  5.7  7.7 MeV Close to D*D* threshold=4017 MeV Mass consistent with each other but width ~2  difference Interference with other amplitudes may change the results Coupling to  D*D* is much larger than to  h c if they are the same state Will fit with Flatte formula PDG2012: M D*+ + M D*0 =  0.2 MeV

Summary  QCD-motivated spectroscopies predicted by theorists do not seem to exist - evidence for Pentaquarks has disappeared - H-dibaryon with mass near 2m  is excluded at stringent levels - No hint on D s0 ++ isospin partner state of D s0 + (2317) -  Numerous non-qq mesons not specific to QCD have been found - Baryonium in J/    pp at BESII and BESIII ?? - XYZ mesons containing cc and bb pairs  The J PC =1 - - Y(4260) and “  (5S)” have no compelling interpretation - huge couplings to     J/      (nS))  not predicted in any model!! - strong sources of charged Z c (Z b ) states with M near m D(*) +m D* (m B ( * ) +m B* ) 51 _ _ _ _

Back-up slides 52

Z b1 & Z b2, “smoking guns” for non-qq mesons u b d b  decays to  (nS) & h b (nP)  must contain bb pair  electrically charged  must contain ud pair _ _ _ 53

54 f 0 (980)? ?? reflection signal reflection signal e + e -   +  - J/  at Ecm=4.26 GeV BESIII: PRL110,

55 e + e -   +  - J/  from ISR Belle: PRL110, M 2 (  ) vs. M 2 (  J/  ) for 4.15<M(  J/  ) <4.45 GeV 2.(inset) Background events in J/  -mass sidebands 3.Structures both in  and  J/  systems evts in J/  signal region, purity~80%

56 Neutral Z b 0 in Y(5S)  Z b 0  0  Y(nS)  0  0

BESIII collected 3.3/fb for XYZ study

The “Nagara” 6 He event  6 He  5 He  H. Takahashi et al, PRL 87, (1977): M H > 2m  -7.7 MeV 58

2 -+ cc assignment?  c2 ? Mass is too high?: 3872 vs 3837 MeV pinned to: M  ”=3770 MeV &M  2 =3823 MeV  c2   h c (1S) &  c modes expected to dominate Theor: B  K  c2 violates factorization B  Kh c not seen B  K  c2 barely seen Theor:  c2  DD* expected to be tiny Belle & BaBar::  X  DD   X      J/  ±  Y. Kalasnikovaet al arXiv: _ _ _ use theory: c.f.:  (  ’   0 J/  )≈0.4 keV Expt: Y. Jiaet al arXiv:

“  (5S)” is very different from other  states Belle PRL 100, (2008)  (MeV) X10 -2 Anomalous production of  (nS)  +  - Recall Y(4260) with anomalous  (J/   +  - )  Is there a Y b equivalent close to  (5S) 23.6 fb -1 60

The “XYZ” mesons Z b1 (10610) 10,607±2 18±2 1 -  ± ϒ (1,2,3S)/h b (1,2S); BB* ` ϒ (5S)’   ± Z b1 Z b2 (10650) 10,653±2 12±2 1 -  ± ϒ (1,2,3S)/h b (1,2S);B*B* ` ϒ (5S)’   ± Z b2 61

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