The meson landscape

The meson landscape

Scalars and Glue in Strong QCD

New states beyond

Weird baryons: pentaquark problems

“Diquarks,Tetraquarks, Pentaquarks and no quarks”

1

Diquarks, Tetraquarks, Pentaquarks and no quarks

“Exotics: what needs to be measured”

Belle e+e- to + X ???

Claim of Hybrid Charmonium by BELLE

Is this the same as X(3940)?Is it hybrid charmonium as claimed?….probably not, but this might be…….

e+e- \to psi pi pi BaBar sees new vector cc*

Y(4260)

Maiani talk

Y(4260) = Non resonant S-wave threshold

Y(4260) Three Possibilities

Experimental distinctions….later this talk

Especially, but not exclusively, the role of charmoniumin achieving these aims

Strong QCD:

What theory expects

Can experiment rule it out?

What present and future experiments can test for…Glueballs; hybrids; diquarks; tetraquarks; pentaquarks

2S: 1-

1S: 1-

1D: 1-

2+

1+

0+

9460

10023

9860

9893

9913

3686

3097

3415

3510

3556

3772

cc*)

Narrow below MM threshold

2S: 1-

1S: 1-

1D: 1-

2+

1+

0+

9460

10023

9860

9893

9913

3686

3097

3415

3510

3556

3772

cc*)

Lattice QCD: Linear: Flux tube…..implies…

Gluonic hybrid mesons

c.m

.c.m

.

e.g. p=1e.g. p=1

Exciting the flux tube

Lattice and model agree spectrum; decays in FT not yet lattice

Glueballs spectrum from Lattice

Far away from qq* lowest multiplets… except for 0++

Hybrids later: First – what can be said about glueballs?

2S: 1-

1S: 1-

1D: 1-

2+

1+

0+

770 780/1020

1460

1700

I=1 vector : I=0 nn*; ss*

1320 1270/1525

1300 1285/1530

1420

+ Problem of nn* ss* flavour mixing

Clean below S-wave MM thresholdsAnd no prominent G expected

Glueballs also predicted: Strong QCD spectrum from Lattice

Far away from qq* lowest multiplets… except for 0++

Only scalar glueballbelow 2 GeV

2S: 1-

1S: 1-

1D: 1-

2+

1+

0+

770 780/1020

1460

1700

I=1 vector : I=0 nn*; ss*

1320 1270/1525

1300 1285/1530

1420 1370/1500/1710

+ Problem of nn* ss* flavour mixing

2S: 1-

1S: 1-

1D: 1-

2+

1+

0+

770

1460

1700

I=1 vector : I=0 JP = 2+ 1+ 0+

13201270/1525

13001285/1530

1420 1370/1500/1710980 980/600

2S: 1-

1S: 1-

1D: 1-

2+

1+

0+

770

1460

1700

I=1 vector : I=0 JP = 2+ 1+ 0+

1270/1525

1285/1530

0+ 1370/1500/1710980/600

? qq* + Glueball

Lattice G =1.6 \pm

2S: 1-

1S: 1-

1D: 1-

2+

1+

0+

770

1460

1700

I=1 vector : I=0 JP = 2+ 1+ 0+

13201270/1525

13001285/1530

1420 1370/1500/1710980 980/600

[qq][q*q*]

2S: 1-

1S: 1-

1D: 1-

2+

1+

0+

770

1460

1700

I=1 vector : I=0 JP = 2+ 1+ 0+

1270/1525

1285/1530

0+ 1370/1500/1710980/600

? qq* + Glueball

Lattice G =1.6 \pm

Data do not imply GBut given lattice and qq*Does consistent pic emerge?

Can data eliminate it; or even make it robust?

Tensor and axial qq*

ss* 1525

nn* 1270

G 2 – 4 GeV

Scalar Glueball and Mixing

s

n

G


Meson

1710

1500

1370

s

n

G


Meson G ss* nn*

1710 0.39 0.91 0.15

1500 - 0.65 0.33 - 0.70

1370 0.69 - 0.15 - 0.70

s

n

G

LEAR/WA102Meson pair decays

Meson G ss* nn*

1710 0.39 0.91 0.15

1500 - 0.65 0.33 - 0.70

1370 - 0.69 0.15 0.70

s

n

0- 0- meson decays LEAR/WA102

FC Kirk

Scalar Glueball and Mixinga simple example for expt to rule out

Nontrivial correlationwith relative masses

heavy

l

lightmiddle

Scalar Glueball and Mixing:how to measure flavour state

Meson G ss* nn*

1710 0.39 0.91 0.15

1500 - 0.65 0.33 - 0.70

1370 0.69 - 0.15 - 0.70

s

n


Meson G ss* nn*

1710 0.39 0.91 0.15

1500 - 0.65 0.33 - 0.70

1370 0.69 - 0.15 - 0.70

s

n

Coming soon from BES and CLEO-c

A flavour filter for 0++ 0-+ 2++mesons and glueballs

>1 billion 1000 per meson

Challenge: Turn Lattice QCD Glueball spectrum into physics

OZI rule and flavor tagging in J/ hadronic decays

Known ss*/nn*

measure ss*/nn*

Example of “known”ss*/nn* = 1– or 2+“ideal” flavour states


• In J/ hadronic decays, an or Φ signal

determines the or

component, respectively. OZI rule

dduu ss

/J /J

dduu

ss


/J /J

dduu

ss2++:(1270) 2++:(1520)

Works nicely for 2++ where BOTH are ideal


/J /J

dduu

ss

Fails completely for 0^{++} !!!

Leading diagram if 0+ meson contains qq* only

Extra diagram if 0++ has glueball in its wavefunction

Unusual properties of f0(1370), f0(1500) f0(1710)

Scalar Puzzle

\psi \to 0^{++} V

A consistentpattern in these two experiments can establish role ofScalar Glueball

Challenge: quantify the predictions

Glueballs and central production

G qq*

Reality: qq* (also) produced

How to separate G and qq*? FC Kirk Schuler 97-00

Central Production pp \to pMp 0+ and 2+

qq* G ?

States outside the quark

model:tetraquarks

2S: 1-

1S: 1-

1D: 1-

2+

1+

0+

770

1460

1700

I=1 vector : I=0 JP = 2+ 1+ 0+

1270/1525

1285/1530

0+ 1370/1500/1710

980/600

? qq* + Glueball

[qq][q*q*]

+ +

- -

How can we tell if its this

Or this? +

-

Jaffe model of light scalar mesons

Strong QCD attraction of 3*c 3*f qq into 0+ diquark e.g. Maiani et al heavy and light flavours

Inverted flavour multiplets

1020 ss*

890 su* sd*

780 uu*+dd*770 uu*- dd*

980 (uu*+dd*)ss*980 (uu*- dd*)ss*

800 (su*)uu* (sd*)dd*

500 uu*dd*

1- 0+

e.g.Tetraquarks v Hybrids: One swallow don’t make a summer. Need the whole flock/multiplet.

New states outside the quark

model:

D_s(cs*) states that might beDK or tetraquarks

Leave discussion to Maiani talk


model:

cc* X(3872) anomalous charmonium

An extra narrow charmonium state

Seen in B \to K X(3872)

X(3872) mass compared with DD* thresholds

DD* molecule “tetraquark” Mass = neutral threshold to better than 1 in 10,000

cuc*u* S-wave JPC = 1++ isospin maximally broken

Close+PageTornqvistSwanson

cc*1++ 3550; 1++* 3950:

DD* (neutral) thresholdPsi rho; psi omega S-wave 1++ mesons

P-wave cc*

D

D*

psi

uu* vector

D

D*

D*

D

pi

Energy degeneracy will drivethis >> model details.

Psi rho:psi omega \sim 1Deviations = dynamics

Specific model: Swanson

Decays driven by meson-meson wavefunction

Production by cc* residue: like psiprime

18

Mass coincidenceonly happens withCharm, not strange or bottom

• Molecule or radial 1++ cc*?

• Suzuki: cc* with cc*uu* admixture (also FC+ Page)

• Further tests: Production in B+ bigger than Bo

Test:

X \to K+K-\pi>> K0K0\pi

CLEOc/BES precision test for 1++ 3550 also


model:

Hybrid Mesons

Gluonic hybrid mesons

c.m

.c.m

.

e.g. p=1e.g. p=1

Exciting the flux tube

flux-tube degrees-of-freedom

c.m

.c.m

.

e.g. p=1e.g. p=1

are new degrees-of-freedom, not present in the quark model.

Isgur showed that they have measurable effects on conventional states

Close Dudek: E1 excitation of hybrids = r^2 meson: Cabibbo Radicatti

(Lattice only now beginning to look at this)Costs about 1 to 1.5GeV energy to excite phonon“pi/R”Hybrid nn* @ 2GeV; Hybrid cc* @ 4-4.5GeV

1-+ signals:

resonant? (Pennington); hybrid or molecule? (Klempt)

E1 photoproduction of hybrids gamma p to n H^+ \sim 50% relative to conventional mesons (Isgur; FC Dudek)

2+- also expected. Diffractive Photoproduction!! Should exceed 1-+ strength

flux-tube breaking and decays

c.m

.c.m

.

e.g. p=1e.g. p=1

Break tube: S+P states yes; S+S suppressed

S+S = 0 for hybrid charmonium(FC + Page)

Look for DD_{0,1}; a bit of DD* and absence ofDD or D*D* and of DsDs or Ds*Ds*

\psi f_0; \psi pipi; \chi \eta; h_c \eta also

More new anomalous

charmonium states:

cc* 2++(3930) X(3940) Y(4260)

Belle e+e- to + X ???

Belle Inconsistent strengths?

big

?

radial

??thresholds

and1+

?

Belle Y(3940) claimed “hybrid charmonium”

….but seems also to be in DD* (need to measure b.r)….

Is this the same as X(3940)?Is it hybrid charmonium as claimed?….probably not, but this might be…….


Y(4260)

But small relative to psiprime

\Gamma(e+e-) 5 to 80 eV


But width 90MeV dominantly psi pipi !

f0(980)?

All consistent with predictions for hybrid charmoniumFC+Page 1995

This is a clear distinction with hybrid for which this is ~ zero

Is it really a resonance?

D

D_1 uu * pi pi

psi

e+e- DD_1 is first S-wave charm thresholdand occurs \sim 4.2 GeV !

S-wave, relative mom \sim 0; DD_1 interchange constituents to make psi pipi “strongly”(c.f. Swanson model of 3872 DD* \to psi omega)

e+e- Ds Ds_1 psi KK should show similar

e+e- KK_1

phi pi pi

Future need to do:Compare this with theDD_1 / psi pipi case:

M(pipi); phi (psi) polarisation

Psi polarisation test inX(4260) \to psi pipi

D

D_1 (pipi)_S wave

psi

Hybrid cc* has spin(cc*)=0 (!)Swanson exchange model psi polarised transverseFC Swanson

If spin cc* = 1 (conventional) psi polarisation differentbut model dependence to be understood

In any event, poln measure should be done andcompared with phi in the KK_1 region


model:

Pentaquark baryons

Exotic Pentaquarks Exotic Mesonsgeneral problem with clustered quark models, for example triquark - diquark:

Kochelev, Lee & Vento

S=+2 meson =

suppresses decay width

narrow, strangeness +2 meson near 1600 MeV

apply same logic to

1-+ and 1- - 10 and 10* multiplets

1-- members in 1.2 to 1.6 Gev region

rho( 1250?? 1450;….1700….)omega/phi(1420;1650;1680…..)

Nonet has one I=1 (rho) and two I=0 (omega,phi)10/10* has two I=1 and one I=0

How many vector mesons are there in the 1-2GeV rangeAnd what is the I=0:1 ratio?

Check in e+e- with ISR, photoprod at Jlab …..

ArndtBuccellaCarlsonDyakanovEllisFaberGianniniHuangInoueJaffeKarlinerLipkinMaltmanNussinovOhPolyakovQiangRosnerStechTrillingUVenezianoWilczekXiangYangZhu

If Theta doesn’t exist,then these (and many other theorists)should be congratulated on their creativity

SELEX weird stateArtefact (IMHO)Can discuss later if wish

A conjecture: T.Barnes, F.E.Close, H.J.Lipkin, hep-ph/0305025, PRD.

Reminiscent of Weinstein and Isgur’s KKbar molecules,bound by level repulsion of the KKbar continuum against higher mass qqbar 0+ scalars at ca. 1.3 GeV.

f0(1370) at BES

• f0(1370) (uu*+dd*)

clearly seen in

J/ ,

but not seen in

J/ .

/J

BES IIPreliminary

/J

PWA 0++ components

f0(1370)

NO f0(1370)

MeV

MeVM

40265

501350

dduu


Meson G ss* nn*

1710 + + +1500 - + - 1370 + - -

s

n

G

3 state mixingRelative phases

2S: 1-

1S: 1-

1D: 1-

2+

1+

0+

3686

3097

3415

3510

3556

3772

cc*)

29801S: 0-

36252S: 0-

Either no G with these JPCin this regionor don’t couple strongly to G

2S: 1-

1S: 1-

1D: 1-

2+

1+

0+

3686

3097

3415

3510

3556

3772

cc*)

29801S: 0-

36252S: 0-

Possible 0-+Glueball \sim 3.6 GeVImpact on eta_c’ ??

Compare in B decay, gamma gamma;ee \to psi + eta_c’


model:

D_s(cs*) states

DK

DK

D*K

Whatever makes scalar f_0(980) light (= just below KK)(compared to qq* p-wave)

Probably makes scalar 2317 light (= just below DK)(compared to qq* p-wave)

…and 2460 axial light (just below D*K)

S-wave meson-meson beats P-wave qq* (continued)27

Expt: Are there other cs* 0+ 1+ as well? (thy. confused) Production of two 1+ in B decays via W current Radiative transitions….

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The meson landscape