A Discovery of the tetraquark by the

Sookyung Choi (For the Belle Collaboraon) Gyeongsang Naonal University

JAGIELLONIAN Symposium, Krakow, Poland, June 9 2015

1 Outline

• X(3872) • Charged Charmonium-like states : Z(4430), Z(4200), … • Charged Boomonium-like states : Zb’s • More charged charmonium-like states : Zc (3895), … , more BESIII Zc’s

2

Charmonium & Boomonium spectrum _

3 cc assignments for the XYZ mesons? _ S Olsen, Front. Phys. 10, 101401 (2015)

Z(4430)

no unassigned levels for Y(4360) the (5) charged Zs

- -

the 1 Y(4260) & Y(4360) _ must have a minimal _ Y(4260) Z2(4250) content of ccud X(4160) Z(4200)

Z(4050) Close to D*D* threshold

X(3940) Y(3915) Zc(3900) X(3872) Close to D*D threshold

the X(3940) & X(4160) as the Y(3915) mass and  the ηc(3S) & ηc(4S) would Γ(Y ωJ/ψ) are too imply huge hyperfine high for the χc0(2P) splittings for n=3&4

Neutral XYZ states Charged Z states

4 The list of XYZ states keeps growing (@2014) S Olsen, Front. Phys. 10, 101401 (2015)

5 Models for XYZ Mesons Tetra- _ u c Hybrids _ u _ c _ c c

(π)

_ c _ c _ u _ π u _ c _ u c _ u c (π) c meson - molecules diquarkonium hadro - (diquark-dianquarks)

Ispin triplet neutral doublet & singlet ? charged doublet X(3872)YZ should have partner states: Three missing states in any pictures 6 The X(3872) BKπ+π-J/ψ

ψ’π+π-J/ψ

X(3872)π+π-J/ψ

X(3872) aer 11 years (& >1000 cites, by 2014 Nov)

7 What do we know about the X(3872)? Belle

BaBar

BESIII

CMS

Y(4260)  γX(3872)? MX(3872) = 3871.69 ± 0.17 MeV mD0 + mD*0 = 3871.80 ± 0.17 MeV  “B.E.” = 100 ± 210 keV 8 ΓX(3872< 1.2 MeV (90% CL) JPC=1++ Belle PRD 84, 052004(R): JPC = 1++ or 2-+ CDF PRL 98, 132002: JPC = 1++ or 2-+

1-- 1++, 2-+

0++

LHCb PRL 110, 222001: JPC = 1++ Radiave decays of X(3872) : a probe of the nature of X(3872)

C=+1 X(3872)  γ ψ’, γ J/ψ BaBar Belle LHCb

From T. Skwarnicki (Moriond QCD 2015) 10 Strong decay X(3872)DD* PRD81, 031103(2010) B →K D0D*0 2-dim. Fit 605 fb-1 D*0→D0γ 6.4σ B+&D 0BD00 π→0 D0D*0K +0.7 M =3875.1 ±0.5 MeV −0.5 414fb-1 B →KD0D0π0

347fb-1 D*0→D0π0

BaBar PRD77, 011102(2008)

Belle PRL97, 162002(2006)

Both groups saw a high mass value + 0.6 + 0.4 & a Bf(DD*) ≈ 10x Bf(π+π-J/ψ) M = 3872.9 − 0.4 − 0.5 MeV Agrees with Mass from ππJ/ψ mode + 2.8 + 0.2 Γ(BW) = 3.9 − 1.4 − 1.1 MeV

*0 0 -4 B(BK X3872)xB(X3872D D ) = (0.80±0.20± 0.10)x10 11 Isospin of the X(3872)

No X(3872) charged partner states in BKπ+π0J/ψ Belle PRD 84, 052004(R) + + (If M(X ) > mD++mD*0 ≈ 3877 MeV, Γ(X ) may be wide) & BaBar PRD 71, 031501 0

0 - + 0* + 0 + 0 0 D  B K π π J/ψ B K π π* J/ψ D +m + +m D + D m m

M(π+π0J/ψ) (GeV) M(π+π0J/ψ) (GeV)

12 Isospin mixing in the X(3872)

X(3872)  ρ J/ψ Isospin violang decay modes (each other) with similar BFs ω J/ψ

X(3872)D0D*_ 0 ~ 10 x BF(X J/ψππ )

Eric Braaten: “S-wave DD* molecular components must exist” _

D0 D+

D*- _

D* 0

0 _ 0  X(3872) is mostly |D D* > mixture of |I=0 >& |I=1> 13

_ _ CDF: ~85% of pp_ X(3872) is prompt D0: prompt ppX(3872)X ≈ ppψ’X

D0 PRl 93, 162002

prompt

X(3872) & ψ’ have similar producon characteriscs (i.e. pT- & |y|-dependence, isolaon, etc.)

BX(3872)+X _ c D0 c

ψ’ _

D* 0 14 “hybrid” model for the X(3872)

e.g., Takizawa & Takeuchi PTEP 9, 093D01

D0

+ _ D

c

D*- c _

D* 0

XωJ/ψ decays XρJ/ψ decays producon

15 Charged Charmonium-like states :

Z(4430), Z(4050), Z(4250) , Z(4200) (new) and Z(3885)..

16 The Z(4430)+ Found by Belle in 2007

Belle : 660M BB

S-K Choi et al Belle: PRL 100 142001 R. Mizuk et al Belle: PRD 78 072004

5.2σ

+ M(π ψ’) Not seen by BaBar But both Data seems consistent Charged state cannot be Belle published two more results

Latest one uses 17 4D amplitude analysis  Quantum numbers of the Z(4430)+ Z(4430)+  π+ψ’ in BΚ-π+ψ’ K Chilikin et al Belle: PRD 88 07402 (2013)

Belle : 772 M BB

6.1σ

M2(π+ψ’) Results from 4D fit 4485 MeV

18

1+ is favored over 0- by 3.4 σ 18 Is Z(4430)+ a resonance or rescaering effect ? Taken from T. Skwarnicki (Moriond QCD 2015)

LHCb

19 The Z(4200)+ New from Belle: 4-dim analysis of BK+π-J/ψ

K Chilikin et al Belle: PRD 90 112009 (arXiv: 1408.6457 ) (2014) 20 New state Z(4200)+ π-J/ψ

6.2 σ

13+1

132+1

1+ is favored over 0- by 6.1σ and 2- by 4.4 σ 21 Z(4430)+ π-J/ψ

BKπ+J/ψ with Z(4430) 4.0σ

no Z(4430)

This may support the Z(4430) as an hadro-charmonium other than convenonal tetraquark state

M(Zc(4430))-M(Zc(3900)) = 589 ± 30 MeV Is Z(4430) a radial excitaon of the ground M(ψ’) – M(J/ψ) = 589 MeV 22 state of Zc(3900) ? + + + Z(4050) and Z(4250)  π χc1 0 - + in B  Κ π χc1 PRD 78, 072004 (2008)

> 5 σ

23 Charged Boomonium-like Zb states and neutral partner state:

+ + 0 Zb(10610) , Zb(10650) and Zb(10610)

24 The Y(4260)

+ - + - found by BaBar in e e → γISRπ π J/ψ hadrons) 

- e + (e σ Confirmed by Cleo, Belle and BES

BaBar PRD86, 051102

Ecm (GeV) → Γ(π+π-J/ψ) is large, 10~100 × charmonium

M(π+π-J/ψ) (GeV) Is there a b-quark version of Y(4260)? 25

26 26 26

Energy scan 

ϒ ± keV 110 590 ” (5S) “

ϒ ± keV 0.35 1.75 (4S)

1S 4,5S ϒ ππ Γ ) (Y parent 

Belle: PRL 100 112001

3S 2S

“5S” 4S

6 6 × ~ Signal

~1/5

σ

th

~1/20 Lum

th

ϒ ϒ π π (1S) ? (4S,5S)

+

-

and ISR correcon applied)

Is there any anomaly in

(Connuum subtracon

ϒ ππ , b (nS)

R R

boomonium “ ” bb mesons

New Measurement of _ Belle PRL 108, 122001 (2012) “ϒ(5S)” π+π- ϒ (1,2,3S) ? 121.4 -1

+ -

Υ(3S)π π ) + - ± π π π ϒ ( 2 M

Υ(2S)π+π-

) ± π ϒ ( 2 M

+ - π+π- Υ(1S)π π

) ± π ϒ ( 2 M

2 + - M (π π ) 27 + - Belle PRL 108, 122001 (2012) “ϒ(5S)” π π ϒ (1S) ? 121.4 -1

Υ(3S)π+π-

) + - ± π π π ϒ ( 2 M

M(ϒ(3S)π±)

Υ(2S)π+π-

M(ϒ(2S)π±) π+π- Υ(1S)π+π-

± M(ϒ(1S)π ) 28 Belle PRL 108, 122001 (2012) - + 121.4 -1 “ϒ(5S)”  π Zb1,2  π+ϒ (1,2,3S)

MeV + MeV π 10,660 10,610

ϒ (3S)

ϒ (2S)

ϒ (1S)

+ M(ϒ(nS)π )max 29 Belle PRL 108, 122001 (2012) “ϒ(5S)”  π-Z + 121.4 -1 Boomonium spectrum b1,2 +  π hb(1P, 2P)

MeV + MeV π 10,660 10,610

30 Summary of parameter measurements

Belle PRL 108, 122001 * B +m B* B m 2m

B d b

B* Z (10610) Z (10650) d b b b M=10607.2±2.0 MeV M=10652.2±1.5 MeV Γ=18.4±2.4 MeV Γ=11.5±2.2 MeV

31

_ _

Zb(10610)BB* & Zb(10650)B*B* _

“ϒ(5S)”  π-(BB*)+ “ϒ(5S)”  π-(B*B*)_ +

± Z (10650)± Zb(10610) b

_ _ M(B*B*)

M(BB*) arXiv : 1209.6450

_

Bf(Zb(10610)BB* _

_ =6.2±0.7 Bf(Zb(10650)B*B* Bf(Z (10610) +(bb) _ =2.8±0.4 b π + Bf(Zb(10650)π (bb)

32 0 0 0 Zb search in ϒ(5S) π π ϒ (1,2S)

Belle PRD 88 052016 (2013)

33 More Zc states

34 Discovery chain from Y(4260) to Zb(c)’s

+ - + - by BaBar in e e → γISRπ π J/ψ Y(4260) discovered

Is there a b-quark equivalent?

??? Yes, & it decays to Zb states + - ϒ(5S)  π Ζb π+π- ϒ (1S) Are there c-quark versions of Zb’s?

 Yes, many Zc’s !!

35 PRL 110, 252002 (2013) Zc(3895) by Belle arXiv:1304.0121 + - - + + - e e (γ)Y(4260)π Zc(3895)  π π J/ψ

Z(4430) Y(4360) BESIII data clearly Y(4260) P + Z2(4250) establish J =1 X(4160) From DD* + π Z(4050)

X(3940) Y(3915) Zc(3900) X(3872)

π-

 Mass = (3894.5 ± 6.6 ± 4.5) MeV Neutral XYZ states  Width = (63 ± 24 ± 26) MeV Charged Z states  Fraction = (29.0 ± 8.9)% (stat. error only)  Significance = 5.2 σ 36 - + + Y(4260)π Zc(3900) π π J/ψ

BESIII: PRL 110, 252001 arXiv:1303.5949

 Mass = (3899.0±3.6±4.9) MeV  Width = (46±10±20) MeV  Fraction = (21.5±3.3±7.5)%  Significance > 8 σ 37 Zc states from BESIII

38 Summary of Zc states discovered in the BESIII experiment

From Xu Xinping, C. Yuan (QWG2014) 39 Z(3900)0 & Z(4020)0 search at Belle From Anna Vinokurova at CHARM2015 arXiv : 1501:06351 JHEP..

+ - + - M(ηc π π ) (GeV) M(ηc π π ) (GeV)

40 X(3872) and other 1+ XYZ states Molecules Level Diagram ? (By S. Olsen Front. Phys. 10, 101401 (2015)

P + The J =1 boomonium states? (See above ref.)41 Summary  Belle discovered many XYZ states .  List of XYZ mesons keeps growing, however, their nature is sll in a mystery.

Remains opportunies for LHCb and BelleII. 10 years aer the X(3872)’s discovery, this is the most highly cited B-factory _

paper and  BE = ( mD *0_ + mD0) - MX(3872) gets smaller, and now the BE= 0.1 +- 0.2MeV  Models for the X(3872)YZ suggest the existence of addional states  Z(4430)+ from Belle is confirmed and J P is conclusively 1+.  Argand plot (LHCb) shows resonance behavior  Charge and quantum numbers rule out convenonal charmonium interpretaon  But sll non-resonant interpretaon ( rescaering) possible.  NEW charged state Z(4200) + is observed in BJ/ψ π+ K- decay. The quantum number is 1+. Evidence of the Z(4430)+  π+J/ψ is found. + + 0  Zb(10610) , Zb(10650) and Zb(10610) are the first candidate of ispin triplet in Belle.

 Many Zc states are recently discovered from BESIII (Belle) : including two sets of Isospin triplet states Zc(3900) and Zc(4020). 42 Back-up slides

43 …

+ - M = 3872.0±0.6±0.5 MeV X(3872)ρJ/ψπ π J/ψ X(3872) / γχc1

3 C=+ X(3872) ≠ 1 D2 (ψ2) M ≈ m 0+m 0 X(3872) D D* 44 The Belle experiment

TOF counter

Peak luminosity recorded at KEKB: L=2.1 x 1034/cm2/sec with crab cavies

45 QCD hybrid?

c _ c

lightest 1++ hybrid ~4.4 GeV

excited-state hybrids

ground-state hybrids

charmonium

L Liu et al., JHEP 1207, 126 (2012) (Hadron Spectrum Collaboraon) 46 0 + - B →X(3872)K π PRD91, 051101 (R) (2015)

0 + – + – B(B →X(K π )K*+NR) B(X→J/ψπ π ) = (7.9±1.3±0.4) x 10–6

+ 0 – + – (B(B →X(K π )K*+NR) B(X→J/ψπ π ) = (10.6±3.0±0.9) x 10–6)

[both K*and (K+π–)NR]

47 Results by Adding Z+ (LHCb) PRL 112, 222002 (2014)

K* vetoed

4-dim amplitude analysis BKπ+ψ’

48 + Argand plot for Zc(4200)

Clearly shows Resonance-like change Much larger errors and impossible to of the amplitude Draw any conclusion yet.

Unlike LHCb, Belle have two plots for two helicity amplitudes including

higher waves. For S-wave, H1 = H0 49 Belle PRD 82, 091106R (2010) Energy scan to search for anomalous structure Total 29.8 -1

Rϒ(nS)ππ =

Rb =

BaBar PRL 102, 012001 (2009)

10.865 ± 0.008 GeV

+ - Recall Y(4260) with anomalous Γ(J/ψ π π ) ⇒ Is there a ϒb equivalent close to ϒ(5S) 50 _ _ B-B* & B*-B* molecules??

± Z (10610)± B Z (10650) B*

b b b b _

b _ b _ _ B* B* _ _ B-B* “molecule” B*-B* “molecule” M –(M +M ) = + 2.7 ± 2.1 MeV Zb(10610) B B* M –2M = + 2.0 ± 1.8 MeV Zb(10650) B* Slightly unbound threshold resonances??

Belle: M=10607.2±2.0 MeV M=10652.2±1.5 MeV Γ=18.4±2.4 MeV Γ=11.5±2.2 MeV

PDG: MB + MB* = 10604.5±0.6 MeV MB* + MB* = 10650.2 ± 1.0 MeV 51 BESIII collected 5 / above 4GeV for XYZ study

BESIII

Y(4260)  γX(3872)

52 CLEOc data

at 4.17 GeV: 1304.3036

• M = 3885±5±1 MeV • Γ = 34±12±4 MeV • 81 ± 20 events • 6.1σ 53 0 Zc(3900) ? ( a neutral isospin partner state)

0 Zc(3900)

First hint from

54 0 Search for Zc(3900)

0 Zc(3900)

This establishes the Isospin triplet of Zc(3900) 55