how babar can decide what charmonium-like states 4260, 4360…. really are

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How BaBar can decide what charmonium-like states 4260, 4360…. really are. The accidental discovery of a new spectroscopy?. Work by FC with Clark Downum (in PRL) and Chris Thomas (preliminary). 4 to 4.5 GeV region. Gluonic charmonium (hybrid) predicted couples to DD1 and D*D0. - PowerPoint PPT Presentation

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How BaBar can decidewhat charmonium-like states4260, 4360…. really are

The accidental discovery of a new spectroscopy?

Work by FC with Clark Downum (in PRL) and Chris Thomas (preliminary)

4 to 4.5 GeV region

Gluonic charmonium (hybrid) predictedcouples to DD1 and D*D0

Strong attractive forces between D* D1 also between DD1 and D*D0

How BaBar can resolve the dynamics !

2

And enigmatic state(s) observed in expt

1++(3872) 1--(4260)

JPC?(4430)

I=1 !?

DD* DD1

D*D1

17

1- - (4360) psiprime pipi

D*D1

3

1++(3872) 1--(4260)

JPC?(4430)

I=1 !?

DD* DD1

D*D1

17

1- - (4360) psiprime pipi

D*D1

all areS wave in s-channel!

4

Why are nuclear binding energies \sim O(1) MeV per nucleon ?

5

Why are nuclear binding energies \sim O(1) MeV per nucleon ?

Pi exchange is in P-wave= penalty

6

Why are nuclear binding energies \sim O(1) MeV per nucleon ?

=> binding energies \sim O(100) MeV per hadron

Pi exchange is in P-wave= penalty

What if Pi exchange is in S-wave= no penalty

7

Why are nuclear binding energies \sim O(1) MeV per nucleon ?

=> binding energies \sim O(100) MeV per hadron

Pi exchange is in P-wave= penalty

What if Pi exchange is in S-wave= no penalty

Can happen for D1 => D* pi in S wave

8

Why are nuclear binding energies \sim O(1) MeV per nucleon ?

=> binding energies \sim O(100) MeV per hadron

Pi exchange is in P-wave= penalty

What if Pi exchange is in S-wave= no penalty

Can happen for D1 => D* pi in S wave

D1D* deep bound molecules

And in S-wave = 1^{- -}Examples 4260; 4360 …..9

1++(3872) 1--(4260)

JPC?(4430)

I=1 !?

DD* D*D1

D*D1

17

1- - (4360) psiprime pipi

D*D1

all areS wave in s-channel!

gluonic degrees-of-freedom

Costs about 1 to 1.5GeV energy to excite phonon“pi/R”Hybrid qq* @ 2GeV; Hybrid cc* @ 4-4.5GeV

Barnes FC Swanson 93

11

R

Predicted 1-+ Hybrid masses (with spin splittings)

charmonium

Predicted 1-+ Hybrid masses (with spin splittings)

charmoniumNear D(L=0)+D(L=1) thresholds: DD0; DD1; D*D0;D*D1 and strongly coupled to these channels…..how distinguish hybrid from DD1 etc molecules?

Predicted 1-+ Hybrid masses (with spin splittings)

Spin hyperfine splittings

1- - (4.25) Y(4260?)1- + (4.1) HQLGT0- + (3.95) X(3940?)

Barnes FC 82Chanowitz Sharpe

e+e- feebly coupled

e+e- \to \psi + X?

14

Novel states in e+e- to + X

???

0-+;1-+

15

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

Y(4260)

\Gamma(ee) 5-80eVCompare \sim 1 keV !!

But width 90MeV typical hadron !

psi pipi violate OZI

D

D_1 uu * pi pi

psi

16

To do more need dynamics:Production; decays; selection rules

Lattice hints about dynamicsHybrids and DD1 decays

35/18

Beyond Spectroscopy

17

What properties

18

What properties

Michael McNeile 06

FC Burns 06

confirms Flux Tube for hybrid:conventional

Lattice S-wave decays now calculated Michael McNeile

Exactly WHAT is Lattice revealing about dynamics:What significance if ratio \sim 2?

18

2

qq* create in S=1

qq* create in S=0 0

19

J – S = “L” Factorisation of S and L

qq* created in S=1

Factorisation and S=1 creationis powerful result if generally true.

Determine nature of Y(4260) by DD_1 pattern

20

SL Factorisation and S=1selection rules for psi*(cc*) \to DD_1

Also applies to KK_1 decays of ss* vectorse.g. ISR around 2.2 GeV

21

4260 decays….

…using strong selection rulesto distinguish candidates…

Conventional charmoniumHybrid charmonium Tetraquark csc*s*; Charm molecule D*D1 or DD1

22

flux-tube breaking and hybrid decays

c.m

.c.m

.

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

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

Isgur Paton 92 light exotics

FC Page 95 all

Look for DD_1 and D*D_0 near threshold

Absence of DD; DD*; DsDs …

24

Y(4260): D_s and D_s* channels

NoDsDsresonance

eliminatestetraquarkcsc*s*

25

Y(4260): D and D* channels

NoDDDD* orD*D*resonance

25

All consistent with predictions for hybrid charmoniumFC+Page 1995

Search DD_1 and D*D_0 in DD\pi\pi

If NOT hybrid cc* then why not/where is it ?!27

The large psi +pi pi = hint of large D(*)D1

D

D_1 uu * pi pi

psi

e+e- psi(hybrid) D(*)D_1

S-wave, relative mom \sim 0; DD_1 interchange constituents to make psi pipi “strongly”

28

The large psi +pi pi = hint of large D(*)D1

D

D_1 uu * pi pi

psi

e+e- psi(hybrid) D(*)D_1

S-wave, relative mom \sim 0; DD_1 interchange constituents to make psi pipi “strongly”

28

Problem: Heavy cc* preserve their spin. Psi has cc* with S=1 Hybrid has cc* with S=0 (h1c eta or etac omega ?)

Problem: and other states: 4360;4430…

Hybrid affected by thresholds

Attractive force from pi exchange:

4260 a result of D1D* (!!) threshold: look for e+e- \to DDbar + 3pi

And what about 4360 in psiprime pipiand 4430 in psiprime pi …..????

29

The Answer: A new spectroscopy?

• At least…..something unexpected!

• 1++(3872) DD* via \pi exchange in p-wave

• 1– (4260 etc) D1D* via \pi exchange

………

30

The Answer: A new spectroscopy?

• At least…..something unexpected!

• 1++(3872) DD* via \pi exchange in p-wave

• 1– (4260 etc) D1D* via \pi exchange

in s-wave!

31

D* to D pi (P wave) O(q^2)DD* to D*D binding O(1 MeV)X(3872)

N N pi: deuteron; O(1 MeV)

32

D* to D pi (P wave) O(q^2)DD* to D*D binding O(1 MeV)X(3872)

N N pi: deuteron; O(1 MeV)

32

1++(3872)DD*

D* to D pi (P wave) O(q^2)DD* to D*D binding O(1 MeV)X(3872)

N N pi: deuteron; O(1 MeV)

D1 to D* pi (S wave) O(mA-mB)^2D1 D* binding O(100 MeV)

M = D*D1(4440) - O(100MeV) 4260; 4360 ??33

Look at I=1 D1D* 1^{--}S wave pi exchangeFind it does NOT bind

34

I=1 feeble binding if anyZ(4430)Liu et al PRD77 034003

35

I=1 feeble binding if anyZ(4430)Liu et al PRD77 034003

I=0 strong binding

36

Binding Energy: variational wfns

Ground state B.E can be 100-200 MeV !! Radial excitation bound also??37

Psi(1S)pipi (4260)

Psi(2S)pipi (4360) and (?) 4600

38

2S

1S

4360

4260

D*D1 threshold 4430 I=1

D*D1 spectroscopy

1P 4350

Potential is similar to Coulomb

39

2S

1S

4360

4260

D*D1 threshold 4430 I=1

Vector D*D1 spectroscopy

D*

D_1 uu * pi pi

cc* psi

40

2S

1S

4360

4260

D*D1 threshold 4430 I=1

Vector D*D1 spectroscopy

D*

D_1 uu * pi pi

cc* psi

1S; 2S

(1S; 2S)

41

2S

1S

4360

4260

D*D1 threshold 4430 I=1

Vector D*D1 spectroscopy

Psi(2S) pi pi

Psi(1S) pi pi

42

2S

1S

4360

4260

D*D1 threshold 4430 I=1

Vector D*D1 spectroscopy

Psi(2S) pi pi

Psi(1S) pi pi

DD pi pi pi

43

The immediate test is 4260 decay to

Then look for other exotica. Also in Bottomonium and strangeonium

Phys Rev Letters (in press)

44

Since PRL: (n.b. preliminary - not yet guaranteed)

Sensitivity to D1 and D0 widths for pointlike mesons (value of h)

Effect of finite D meson size (h function of momentum)

Effect of extended pion (Lambda)

And discovery of DD1/D*D0 molecules too: including exotic J(PC)=1(-+)

45

h^2 width of D_1 to D^* \pi

D and pi pointlike:

Data: h \sim 0.7 – 0.8

h=1 3800

h=0.9 4050

h=0.8 4250

h=0.7 4350

Pion size (Lambda)

Reduces BE:

Extended pion provides smaller force

BE tends to zero.

Bad news

Pion size (Lambda)

Reduces BE:

Extended pion provides smaller force

BE tends to zero.

Bad news

Good newsFinite D size:

h(q) => h(0) increases to > 1

Scale of BE increases

51

52

4260

4360

Threshold 4440

52

Surprisingly robust !

Can force-fit because so sensitive so not a real “pre”-diction

Need direct unambiguous tests = decay channels

53

Surprisingly robust !

Can force-fit because so sensitive so not a real “pre”-diction

Need direct unambiguous tests = decay channels

Look for D Dbar pi pi pi (for D1 D* deep bound molecules)

Look for D Dbar pi pi (not D*D*) for DD1/D*D0 molecules and threshold “accidents”

53

Surprisingly robust !

Can force-fit because so sensitive so not a real “pre”-diction

Need direct unambiguous tests = decay channels

Look for D Dbar pi pi pi (for D1 D* deep bound molecules)

Look for D Dbar pi pi (not D*D*) for DD1/D*D0 molecules and threshold “accidents”

DD1/D*D0 molecules also: and exotic 1-+

Look in e+e- \to (D Dbar pi pi) gamma

54

D*D1 threshold4430

D D1 threshold4290

4260

4360

55

D*D1 threshold4430

D D1 threshold4290

D D1 b state or hybrid at threshold4260

spurious4360

Option 1: 4360 spurious; 4260 hybrid or cc* attracted to DD1 threshold

D D pi pi ( DD1 or D*D0; not D*D* )

560

D*D1 threshold4430

D D1 threshold4290

1S psi pi pi4260

2S psiprime pi pi4360

Option 2: 4360 and 4260 D*D1 molecules

D D pi pi pi57

4260 in psi pi pi @ 90 MeV width MUST be due to some charm meson pair

Finding which => reveals dynamicsin the 4 to 4.5 GeV region where hybridsalso predicted.

DDpipi (not D*D*) and DDpipipiare where the answers are to be found

The antidote to Angels and Demons: available from Amazon et al

e+e- KK_1

phi pi pi

Intriguing resonantsignal at 2175

2175 – m(phi)=4265 – m(psi)!!??

41/12

Study KK1 pattern

Psi(1S)pipi (4260)

BaBar and Belle and CLEO

Psi pipi (4260)

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