Hadron Spectroscopy with avariety of flavors
Toru Iijima

Kobayashi-Maskawa Institute
Nagoya University
December 15, 2012

Quarks to Universe

How quarks acquire their mass and form hadrons ?

Quest in low-energy QCD
Are there exotics beyond meson(qq) /baryon (qqq) ?
Sakata Model(p, n, Λ)

6 quark model

Gell-Mann(u,d,s)qqIIIII

uctup

charm

topflavor

dsbcolor (R,G,B）

down strange

Ordinal Hadrons

mesonIbaryon

q=u, d, s, c, b, tbottom

New Hadrons（Exotics）

Tetra-quark Penta-quark

MoleculeqqqQCD just require hadrons to be colorless, and allow exotics.
Such exotic states exist ?
3

Gell-Mann 1964

Existence of such exotics have long been discussed
4
since the birth of the quark model.

Discoveries in 1974
 Discovery of J/ψ SLAC, Burton Richter et al.
 BNL, Samuel Ting et al.

c c

And following qurkonium spectroscopy established physicalexistence of quarks and qq picture of mesons.

5Discoveries at B-factories
 Discovery of X(3872) and other many XYZ states etc.
 Unexpected bonus of the B-factories

Integrated luminosity (fb-1)

Discoveries of new resonances at BelleY(4660)Y(4008)
DsJ(2860)
DsJ(2700)
Xcx(3090)
X(3940), Y(3940)
Σc* baryon
tripletD0*0 & D1*0Z(4430)

Y(4320)χc2’Y(4260)

X(3872)
DsJ(2317/2460)
ηc’ & e+e-cccc

6Z(4430)
cu dc

X(3872)cu uc

Charmonium-like Spectroscopy
Above DD threshold?

Below DD thresholdwell understood by

4 αS
VQCD =−+ kr
3 r

We do not understood yet how hadrons areformed from QCD.

7XYZ at B Factories
StateMass (MeV)

Width (MeV)

DecayProductionYs(2175)

2175±8

58±26

φf0

ISR

X(3872)3871.84±0.33<0.95J/ψππ, J/ψγ

B decayX(3872)3872.8 +0.7/-0.6

3.9 +2.8/-1.8

D*0D0, J/ψω

B decayY(3915)3915±417±10J/ψωγγZ(3940)3929±529±10DD

γγX(3940)3942±937±17

DD*

Double-charmY(3940)3942±1787±34J/ψωB decay

Y(4008)4008 +82/-49

226 +97/-80

J/ψππISR

Z(4051)+4051 +24/-43

82 +51/-28

πχc1

B decayX(4160)4156±29

139 +113/-65

D*D*Double-charmZ(4248)+4248 +185/-45

177 +320/-72

πχc1

B decayY(4260)4264±1283±22J/ψππISRX(4350)

4350 +4.7/-5.1

13 +18/-14J/ψφγγ

Y(4350)4361±1374±18ψ’ππISR

Z(4430)+4433±545 +35/-18

ψ’π

B decayY(4660)4664±1248±15ψ’ππISR

Yb(10890)

10889.6±2.3

54.7 +8.9/-7.6ππΥ(nS)e+e- annihilation

Zb(10610)

10608.4±2.0

15.6±2.5(Υ(nS) or hb) πΥ(5S) /Yb decay

Zb(10650)

10653.2±1.5

14.4±3.2(Υ(nS) or hb) πΥ(5S) /Yb decay

Tetraquark“Di-quark”ucc uD(*)D(*) Molecule
π ccuuHybridccg8

The KEKB Collider
SCC RF(HER)

ARES(LER)- (8.0GeV) × e+ (3.5GeV)e
Belle detector⇒Υ(4S) →BB⇒Lorentz boost:βγ = 0.425
 Finite crossing angle- 11mrad ×2
 Operated 1999-2010

Ares RF cavity

Peak luminosity

e+ source

2010/10/29

Toru Iijima, seminar at Konan

2.1 x 1034 cm-2s-1 !

9Luminosity at B Factories∫ L > 1ab−1@ Belle

10

Belle Detector
 Acceptance: 0.9 ×4π
 Vertex resolutions(J/ψ ll) ~75nm
 Momentum resolution
σ(Pt) = 0.19・Pt ⊕ 0.34/β % Energy resolution
σ(Eγ)/Eγ =1.8% @ 1GeV Particle IDe, µ, π, K, p
 Minimum bias trigger
Evis >= 1GeV & Ntrk >= 2& Ncluster >= 4
essentially no loss for BB.
11

Production of cc in B Factories
B factories can produce charmonium (-like) states
in four ways.

12

World-wide Activity

BES III

CLEO

Results are mainly from Belle for this talkChamonium-like Exotics14X (3872)
Discovery by Belle in 2003, followed by D0, CDF, BaBar.

(90%CL)15

X(3872) at LHC
CMS (40 pb-1,√s = 7 TeV)R≡

CMS PAS BPH-10-018

σ ( pp → X(3872) +K ) × Br(X(3872) →J /ψ π +π − )σ ( pp → ψ (2S) +K ) × Br(ψ (2S) →J /ψ π +π − )=0.087 ± 0.017 ± 0.009
LHCb (34.7 pb-1,√s = 7 TeV)
arXiv: 1112.5310

σ ( pp → X(3872) +K )× Br(X(3872) →J /ψ π +π − )=[4.7 ± 1.1 ± 0.7] nb

M X (3872) = [3871.95 ± 0.48 ± 0.12]MeV

Looking forward to results with >1fb -1 data.

16

PC
J of X(3872)
CDF(780pb-1) PRL 98, 132002 (2007)

1++2-+1-0++

Belle (711fb-1) PRD 84, 052004 (2011) BaBar (420fb-1) PRD 82, 011101 (2010)• All JPC values other than 1++ or 2-+ are ruled out with high confidence.
• Need more statistics to distinguish 1++ vs 2-+.

Properties of X(3872)
 C = +1

 JPC = 1++ or 2-+
 I=0X(3872)  J/ψ γ, J/ψ ρ seen
Angular distribution
No charged partner so far

isospin violating decay X(3872)  J/ψ ρ (π+π-) Mass just around D*D

 M X − M D *0 − M D 0 = − 0.12 ± 0.35 MeV M X − M D *+ − M D − = − 7.74 ± 0.35 MeV

 Possible interpretation
 Conventional cc : cc1(23P1) for 1++, hc2(11D2) for 2-+
 Exotics:
 D*0 D0 molecule : [cq ][c q] Tetra-quark :[cq][c q ]D*0 D0 molecule

Tetra-quark18

Z(4430)+, Z (4050)+, Z(4250)+ by Belle Belle found Z(4430)+ in BK π+ ψ’ decays.
 One-dimensional fit on ψ’π+ distribution afterK*(890) /K*(1430) vetos.
PRD80, 031104(2009) Confirmed by analysis with a full Dalitz plot.
2+19M = (4443 +15)MeV/c−12 −13

PRD80, 031104(2009)+74
Γ = (107 +86−43 −56 )MeVM2(ψ’π+) Belle found also another two states,Z(4050)+ & Z(4250)+, in BK π+ χc1 decays.
2M1 = (4051± 14 +20−41 )MeV /c2+180
M 2 = (4248 +44)MeV/c−29 −35+47
Γ1 = (82 +21−17 −22 )MeV+316Γ2 = (177 +54−39 −61 )MeV

Their minimum quark
content must be exotic:cc ud19

Bottomonium-like Exotics

20

Anomalies in ϒ(5S) decayϒ(11020)

11.00

10.75

ϒ(10860)
260

Mass, GeV/c22M(B)
10.50

10.25

10.00

9.75

ϒ(4S)
2
ϒ(3S)

430

1

ηb(2S) ϒ(2S)290

partial Γ(keV)
9.50

Γ[ϒ(5S) →ϒ(1,2,3S) π+π–]>> Γ[ϒ(4,3,2S) →ϒ(1S) π+π–]ηb(1S)
JPC = 0π+π–hb production

330
hb(2P)
190

hb(1P)

hb(2P)

hb(1P)

6

Belle PRL108,032001(2012)

ϒ(5S) → hb(1,2P) π+π– are not suppressed

ϒ(1S)

-+ -1

Belle PRL100,112001(2008)

Expect suppression ∼ΛQCD/mb
1+-Heavy Quark Symmetry
Violation

21

Anomalies in ϒ(5S) decayϒ(11020)

11.00

10.75

ϒ(10860)
260

Mass, GeV/c2

2M(B)
10.50

π–

ϒ(4S)
2
ϒ(3S)

10.25

430

10.00

ηb(2S) ϒ(2S)

9.75

9.50

ηb(1S)
JPC = 0π+hb(2P)

hb production⇒ via intermediatecharged states Zb

1290

partial Γ(keV)

Z+bhb(1P)

6

ϒ(5S) → hb(1,2P) π+π– are not suppressed
Expect suppression ∼ΛQCD/mb

ϒ(1S)

-+ -1

1+-

Heavy Quark Symmetry
Violation22

hb (1P, 2P) π+ πhb(1P) π+hb(2P) π+M miss (π ) to look at hb π+++Fit with A(Z b1 ) + A(Z b 2 ) + A(NR)
Two peaks at the positions
same as ϒ(nS)π+π−
23

Charged Bottomonium-like Zb+ in ϒ(nS)π+Two peaks at the same positions in the 3 modes.
ϒ(1S)

ϒ(2S)

ϒ(3S)

Two resonances: Zb+(10510), Zb+(10560)24

Zb(10610) & Zb(10650)

M=10608.4±2.0 MeV

M=10653.2±1.5 MeV
Γ=15.6±2.5 MeV
Γ=14.4±3.2 MeV
25

Molecular Explanation of Zb+

Bondar et al, PRD84,054010(2011)

Proximity to thresholds favors molecule pictureZb+(10510)

Zb+(10560)

ūū

B-

B*-

Each of them is mixture ofspin triplet and singlet bb

This model explains• Why hb is unsuppressed relative to • Relative phase ~0 for  and ~1800 for hb• Production rates of Zb(10610) and Zb(10650) are similar widths

If Zb+ is B*B(*) molecule, it should decay into B*B(*)…
26

Study of Zb→B*B(*)
For the ϒ(5S) →B*B(*) π+ channel:_ Fully reconstruct one B meson in five exclusive decaymodes.
 Look at recoil mass of Bπ (for missing B) rM(Bπ)
and of the pion (for two B combination) rM(π).

27

__Clear BB*π and B*B*π signals
Full reconstruction of one Bin 5 modes
M(B)→ B(*)B(*)π ]BF[ ϒ(5S)__ BB _
BB* +_BB*
B*B*

Mmiss(Bπ)
recoil masspreliminary

Select two peaks_BB*π_BBπ_
B*B*π121.4 fb-1significance<0.60 % at 90% C.L.
(4.25 ± 0.44 ± 0.69) %(2.12 ± 0.29 ± 0.36) %

9.3σ
5.7σ

28

Observation of Zb→BB* and Zb’→B*B*Zb_M (BB*)

8σ

Z b’ ?

phsp__Zb’ → BB* is suppressed w.r.t. B*B*
despite larger PHSP
Molecule ⇒ admixture of_BB* inZb’ is smallAssuming Zb decays are saturated bythese channels:_M (B*B*)
Z b’

6.8σ
phsp

arXiv:1209.6450

29

Fit ϒ(2S)π0π0 structure

arXiv:1207.4345

Dalitz plot analysis
with Zbs

withouto Clear Zb0 signals are seen in ϒ(2S)π0π0o Significance of Zb0(10610) is 5.3σ (4.9σ with systematics)

o Zb0(10650) is less significant (~2σ)

o Fit gives M(Zb0(10610) ) =10609±8±6 MeV

cf: M(Zb+)=10607.2±2.0 MeV

30

H-Dibaryon search @ Belle CLEO’s observation:

Br(Υ(1S)  d + anything)=3x10-5 large !
 Belle has (102+158) x 106 Υ(1S+2S)

Talk by Bong Ho Kim @ Busan New Hadron WS (Nov.19-21, 2012)
http://newhadron.snu.ac.kr/New_Hadron_Workshop/Home.html

Search ResultsBr (Υ(1S,2S)  H + X ) < 10-6 @ 90%CL.
〜

Future Prospects

33

SuperKEKB/Belle II Lpeak=8x1035cm-2s-1

Nano-beamcrossing

 Higher beam currents
 Smaller beam size Lint = 50ab-1 (goal)e- 2.6 A
New beam pipes& bellows

Improve beam monitorsand control systeme+ Damping ring
Low emittanceelectron gun

O(104) X(3872)
e+ 3.6 A

Reinforce RF systems forhigher beam currents
New positron
capture section

Reinforced background immunity
Improved performance
GRID-based computing

SuperKEKB / Belle II Construction
New beam pipe instock

Installation ofnew magnets

Construction of e+
dumping ring

Belle II waiting
for installation

QC1LE prototype

Beam test of new PID

Beam commissioning: 2015Physics run: 2016-Final Remarks

36Summary of this talk
 Low energy QCD is one of the least understood area of theSM.

 High luminosity B factories have brought many discoveriesof new hadronic states, especially the quarkonium-likeexotics
 Recent discoveries in bottomonium region(Molecular picture seem to be favored.) More data are expected Other exotics states: H dibaryon, pentaquark (including

heavy flavor), Tcc(ccud)…

 New data from LHC, SuperKEKB, …

 Collaboration w/ lattice QCD is essential.
 Impact on Astro-particle physics and cosmology.

“New Hadron”
Grant-in-aid for innovative scientific research area
”Elucidation of new hadrons with a variety of flavors”.

Crossover
Low energy QCD is one of the least understood partof the SM, and makes a developing interdisciplinaryarea.

Crossover is important
Particle Physics

Nuclear Physics

ColliderFixed target

Phenomenology(Model)Lattice QCD

Crossover workshop
新ハドロン x 素核宇宙融合 X HPCI-分野5
2011.6.23-24 @ RIKEN AICS2012.7.12-13 @ Nagoya

Hadron 2013

(XV International Conference on Hadron Spectroscopy) 2013.11.4-8 in Nara (Nara Prefecture New Public Hall ) Co-chairs:
 Atsushi Hosaka (RCNP, Osaka) Toru Iijima (Nagoya) Kenkichi Miyabayashi (Nara) About 200 participants Main topics include













Spectroscopy of light- andheavy-quark mesons
Baryons
Quarkonia
Glueballs, hybrids, and multiquarks
Phenomenological models
Effective field theories
QCD on the lattice
Hadron structure
Hadrons in matter

Heavy-ion collisions
Future facilitiesThank you !

Backup Slides

PRD79, 112001(2009)

Z+ (cont’d)

Belle BaBar does not confirm Z+’s

 Z(4430)+ search in BKπ+ψ’ Z(4050)+/Z(4250)+ search in BKπ+χc1
 Excess is < 2σ w.r.t. Kπ reflection.

 But, do not rule out Belle’s results.
 UL is statistically compatible with Belle

BaBar

PRD85, 052003(2012)

results
Br(B 0 →Z +K − ) × Br(Z + → π +ψ ' / χc1 )BaBar U.L.

BelleZ(4430)+< 3.1 (95%CL)

Z(4050)+< 1.8 (90%CL)

4.1 ± 1.0 ± 1.4+3.7
3.0 +1.5−0.8 −1.6Z(4250)+< 4.0 (90%CL)+19.7
4.0 +2.3−0.9 −0.5

Note: In the BaBar analyses, Z+ amplitudes are added
Incoherently, therefore, interference effects are notincluded. They are included in the Belle analyses (seeS.Olsen’s summary talk at CHARM2012, and also backup) .

43

Exotics in light flavors ?
• e+e- ISR :Y(4260)  π+ π− J/ψ; Y(4360)  π+ π− ψY(2175)  π+ π− φ (f0 φ)seen by BaBar, Belle, BES III• γγ (two-photon)
X(3915)  ω J/ψ; X(4350)  φ J/ψ
What about ωφ, φφ ?

44

γγ  VV(ωφ, φφ, ωω) 870 fb-1 near Υ(nS)[n=1,…5]
 4 charged tracks + π0;

φK+K-, ωπ+π-π0 Signals are extracted by fitting

distribution for each M(VV) bin.

ηc χ χc0 c2

 Obvious structures in low M(VV) region.
 JP of the structure is extracted fromangular distributions.

Phys. Rev. Lett. 108, 232001(2012)45

Maximum CM energy at SuperKEKB

 Want √s12GeV to explore bottomonium

spectroscopy.

 Present attainable Emax = 11.24 GeV; limited by e-linac, e+ BT magnet, QC1E quench limit.

 Study possibility of ramping up HER8.6 GeV, forexample, by S-band linac  C-band.

Preliminary Upper LimitInternational Cooperation
LEPS2

Super-KEKB

GSI/FAIR

J-PARC

JLAB

LHC

BEPCI
I

RHIC
J-LAB