Meson Spectroscopy at B factories

8 GeV e-

3.5 GeV

e+

BaBar Belle

Talk Outline

X(3

872)

Y(4

260)

X(3

940)

Y(3

940)

Y(4

325)

DsJ(2317)

DsJ(2460)

Stephen OlsenU. of Hawai’I

&高能所 北京

PPP7 NTU, TaipeiJune 7-11,2007

B-factories are Charm & Charmonium factories

c & cc meson production mechanisms

• B meson decays

• e+e- annihilation

• collisions

• e+e- radiative return (isr)

D & Ds production in B decays

More than 1 charmed particle/B meson

u

q

d

D,D*,..

,..

s

c

q D,D*,

Ds,Ds*,..

cc production in B decays

j=½

j=½

J = 0 or 1

Spectator model says Jcc= 0 or 1 shoulddominate exclusive BK(cc) decays.

Allowed decays all have Bf~10-3 from PDG2004

cK 0.9 x10-3

JK 1.0 x10-3

J/K* 1.4 x10-3

’K 0.7 x10-3

’K* 0.9 x10-3

c0K 0.6 x10-3

c1K 0.7 x10-3

J/K12701.8 x10-3

BK cc(J=2) still not seen

DD

JPC = 0++, 2++

e+e- cc (continuum)c

c

(e+e-cc)>((4S))

Radiative return

JPC = 1--

cc

e+e- DD

e+e- (cc)

D,D*,..

D,D*,..

e+e- J/ + (cc)J/

X

X (almost) alwayscontains (cc)

C(X) = +1consistent with bkg

c

c0

c’

M(X)

All of these processes have produced

discoveries/surprises

• B decays: c’, X(3872), Y(3940)

• e+e-cc continuum: D**’s,DsJ(2317),…

• DD: Z(3940)

• Radiative return: Y(4260), Y(4320)

• e+e-J/ cc: X(3940)

These results have received considerable

interest

SPIRES: find cn BaBar and topcite=250+

1) Observation of a narrow meson decaying to D+(s) pi0 at a mass of 2.32-GeV/c**2.By BABAR Collaboration (B. Aubert et al.).. Published in Phys.Rev.Lett.90:242001,2003.

Cited 393 times

2) Observation of CP violation in the B0 meson system.By BABAR Collaboration (B. Aubert et al.). SLAC-PUB-8904, BABAR-PUB-01-18, Jul Published in Phys.Rev.Lett.87:091801,2001.

Cited 385 times

3) Measurement of the CP violating asymmetry amplitude sin 2beta.By BABAR Collaboration (B. Aubert et al.).. Published in Phys.Rev.Lett.89:201802,2002.

Cited 364 times

DsJ=most cited

BaBar result

SPIRES: find cn Belle and topcite=250+

1) Observation of large CP violation in the neutral B meson system.By Belle Collaboration (K. Abe et al.). Published in Phys.Rev.Lett.87:091802,2001. Cited 398 times

2) Observation of a narrow charmonium - like state in exclusive B+- ---> K+- pi+ pi- J / psi decays.By Belle Collaboration (S.K. Choi et al.). Sep 2003. 10pp. Published in Phys.Rev.Lett.91:262001,2003Cited 279 times

3) A Measurement of the branching fraction for the inclusive B ---> X(s) gamma decays with BELLE.By Belle Collaboration (K. Abe et al.). Published in Phys.Lett.B511:151-158,2001Cited 278 times

4) An Improved measurement of mixing induced CP violation in the neutral B meson system.By Belle Collaboration (K. Abe et al.). Published in Phys.Rev.D66:071102,2002. Cited 252 times

X(3872)J= 2nd most

cited Belle paper

The D** mesons

B+→D*- π+π+

B+→D-π+π+Belle: 65 M BB

PRD 69, 112002 (2004)

Spectroscopy and allowed transitions of D mesons

The DsJ mesons

DsJ(2317)→Dsπ0 DsJ(2460)→Ds*π0

BABAR: 91 fb-1 PRL 90, 242001 (2003

CLEO: 13.5 fb-1 PRD 68, 032002 (2003

BaBar: 240 fb-1

PRL 97, 222001 (2006)Belle: 449 M BB

hep-ex/0608031

DsJ(2860)→DK

The D**/DsJ meson puzzle(two slides only)

~145 MeV

~145 MeV

~0 MeV

~0 MeV

BaBar

CLEO

Belle

Replace a u/d quark with an s quark

uc

sc

+ ~145 MeV≈(ms-mu)

S-Wave P-Wave

uc

sc

No penalty

Charmonium is of particular interest

because it is a good system to use to search

for non-qq mesons

a cc meson has to fit into these slots:

“XYZ” particles • X(3872)

– J/ in BKJ/

• Z(3930)– DD in DD

• Y(3940)– J/ in BK J/

• X(3940)– e+e- J/X & e+e- J/ DD*

• Y(4260)– J/ in e+e- J/

• Y(4320)– +-’ in e+e-+-’

Are these charmonium states?

Z(3931) DD at Belle

41 11 evts (5.5)

M=3931 4 2 MeV

208 3 MeV

sin4 (J=2)

Matches well to c2’ expectationsM(DD) GeV

Uehara (Belle) PRL 96, 082003 (2006)

Z(3930): candidate for the c2’

3931M= 3931 MeV is

~45 MeV low

=20MeV too narrow?

Masses fromBarnes, Godfrey & Swanson

PRD 72, 054026 (2005)

e+e- J/ X(3940)

e+e-J/ + X

Pakhlov (Belle) PRL 98, 802001 (2007)

X(3940)D*D is strong(DD & J/ not seen)

B(D*DD)>45%

consistent with 100%

B(DD)<41%

From X(3940) → D*D:M = (3943 ± 6 ± 6) MeV = (15.4 10.1) MeV< 52 MeV at 90%CL

Pakhlov (Belle) PRL 98, 802001 (2007)

Higher

statistic

s Belle

results th

is

Summer

Higher

statistic

s Belle

results th

is

Summer

Is the X(3940) the c”?

3940M= 3943 MeV is ~150 MeV low

<52MeV too narrow?

X(3872) in BKJ/

M(J)

’J/

X(3872)J/

PRL 91, 262001

2.9 MeV

Also seen in pp

X(3872)

CDF

hep-ex/0406022

11.6

Production properties similar to those of the ’

X(3872)D0

PRL 93, 072004 (2004)

PRL 93, 162002 (2004)

C=+1 is pretty well established

X(3872)J/ seen in:

&

PRL 96 102002

M( looks like a

X(3872)””J/ seen

CDF Belle

Belle

hep-ex/0505037

Belle

Swanson PL B588, 189(2004)

l

|cosl|

2/dof = 34/9

|cos|

|cos|

2/dof=34/9

0++ 0-+

rule out 0++ & 0 -+

J kxJ

Ruled out by Belle

Angular analysis from CDF

CDF PRL 98 132002 (2007)

1++

or2-+

X(3872) has no satisfactory cc assignment

3872

rJ/ too small& r(J/) too big

c1’

• cJ/ ispin forbidden• D0D00 @ thresh. suppressed• BKcc(J=2) suppressed

c2

Mass is near theD0D*0 threshold

PDG06: mD0+ mD*0 = 3871.1 ± 0.8 MeV

PDG MX3872: 3871.2 ± 0.5 MeV

D*0D0”binding energy” = 0.4 ± 0.6 MeV

CLEO hep-ex/0701016 3871.7 ± 0.4 MeV

My average: 3871.6 ± 0.4 MeV

hh bound states (hadronium)??

p n D D*

deuteron:

loosely bound 3-q

color singlets with Md = mp+mn-

Hadronium (dueson):

loosely bound q-q color

singlets with M = mD + mD* -

attractive nuclear force attractive force??

N.. A. Tornqvist, Phys Lett. B 590, 209(2004)F. Close, P.R. Page, Phys. Lett. B 578, 119 (2003)

E.S. Swanson, Phys. Lett, B588 189(2004) E. Braaten, M. Kusunoki, S. Nussinov, Phy. Rev. Lett. 93, 162001 (2004)

M. Voloshin & L. Okun , JETP Lett. 23, 333 (1976)A. DeRujula H.Georgi & S.Glashow , PRL 38, 317 (1977)

Belle: Threshold peak in BKD0D00

M=3875.4 0.7 0.8 MeV

Br(XD0D00)Br(XJ/)

~ 9

+0.3-1.6

M(D

D)

E

Gokhroo (Belle) PRL 97 162002 (2006)

~2 higher than in the J/y mode

BaBar confirms the B(D0 D*0) K threshold enhancement

BaBar, Moriond 2007

1.41.53875.6 0.7M MeV

The is also 2.5σ high

Molecular models have trouble with a large DD

decay rate

X(3872) = D0D*0 bound state?

• JPC = 1++ is favored

• M ≈ mD0 + mD0*

• Large isospin violation is natural (& was predicted):

|D0D*0> = 1/2(|10> - |00>)

• (XJ/) < (XJ/) was predicted

• (XD0D00) too large?

• XDD peak mass > mD0 + mD0*

Equal mixture of I=1 & I =0

Swanson PLB 598, 197 (2004)

Tornqvist PLB 590, 209 (2004)

Swanson PLB 588, 189 (2004)

Real or virtual DD* state?

hep-ph/0704-0605

J/

DD J/

DD

diquark-antidiquark?u c

ucd c

dcXu= Xd=

B+K+Xu B0K0Xd

BaBar BaBar

Maiani et al predict: M = M(Xu) – M(Xd) = 8 3 MeV

BaBar PRD 73 011101R (2006): M = 2.71.3 0.2 MeV

L. Maiani, F. Piccinini, A. D. Polosa,

V. Riquer PRD71: 014028 (2005)

Predict a doublet of states:

Y(3940) in BK J/

M≈3940 ± 11 MeV≈ 92 ± 24 MeV

Belle PRL94, 182002 (2005)

M(J/) MeV

(Y3940 J/ > 7 MeV (an SUF(3) violating decay)

~

this is 103 x (’ J/ (another SUF(3) violating decay)

if the Z(3930) is the c2’the Y(3940) mass is toohigh for it to be the c1’

Is there a cc slot for Y(3940) ?

Can M(c1’)>M(c2’)?c1’

Mass is lowc”

“ “ “ “c0

’

39403931

e+e- isr Y(4260) at BaBar

233 fb-1

ee+J/pb

(Y4260 J/) > 1.6MeV @ 90% CL

Y(4260)

X.H. Mo et al, PL B640, 182 (2006)

4260

4260

BaBar PRL95, 142001 (2005)Not seen in e+e- hadrons

BES data~3nb

~50pb

Y(4260) at Belle

M=4295 10 +10 MeV

= 133 26 +13 MeV -6

-3

For ’J/ in the same data:

M(’) = 3685.3 0.1 MeV(PDG: M(’)=3686.09 0.04)

Belle hep-ex/0612006

Y(4260) at CLEO-III

Consistent results

13.3 fb-1

ISR(1S)-(4S)

13.3 fb-1

CLEO PRD 74 091104 (2006)

M = 4284+17-16 4 MeV

= 73+39-25 5 MeV

No 1-- cc slot for the Y(4260)

42804260

X.H. Mo et al, hep-ex/0603024

Is the Y(4260) a cc-gluon hybrid?

c c

•qq-gluon excitations predicted in 19787 •lowest 1-- cc-gluon mass expected at ~4.3 GeV •relevant open charm threshold is D**D (~4.28 GeV) • (J/) larger than that for normal charmonium • (e+e-) smaller than that for ordinary charmonium

Horn & Mandula PRD 17, 898 (1977)

Banner et al, PRD 56, 7039 (1997); Mei & Luo, IJMPA 18, 15713 (2003)

Isgur, Koloski & Paton PRL 54, 869 (1985)

McNeile, Michael & Pennanen PRD 65, 094505 (2002)

Close & Page NP B443, 233 (1995)

Y(4260)seems to fit all of the above!!!

DD** threshold in relation to the “Y(4260)”

4.28-mD

D** spectrum

M(J/) GeV

No obviousdistortions

D1D

D2D

A ’ enhancement at 4325MeV

Incompatible with (4415), nor well described by Y(4260)

A single resonance can describe the structure (<5.7 GeV/c2) well

mass=(432424) MeV/c2, =(17233) MeV (statistical errors only)

Nbkg = 3.1 1.0

Nevt = 68 (<5.7 GeV/c2)

2-prob < 5.7 GeV/c2

Y(4260) 6.5 10-3

(4415) 1.2 10-13

Y(4320) 29%

e+e-ISR ’

M=4324 24 MeV

= 172 33 MeV

above all D**D thresholds

S.W.Ye QWG-2006 June 2006

Not Compatible with the Y(4260)

D1D

D2D

298 fb-1 (BaBar) hep-ex/0610057

BaBar hep-ex/0607083

(e+e- DD)

Y(4325)

(e+e- D*D(*)) @ s 4 GeVBelle: ISR + Partial Reconstruction

Pakhlova (Belle) PRL 98, 092001 (2007)

(e+e- D*+D*-)

(e+e- D+D*-)

(4

040)

(4

160)

(4

415)

Y(4

260)

Y(4

325)

D*D*

DD*

DD

tot

The parameters ofthe above-threshold

1– charmonium statesdetermined from fits to totwith incoherent

BW’s are probablynot very reliable

summary (XYZ)• Z(3931) (DD)

– Probably the c2’

• X(3940) (e+e- J/ X)– C=+1

– Could be the c” (albeit with some stretching)

• X(3872):– JPC = 1++

– Br(X J/) large– Br(XD0D00) seen; ~ 9xBr(XJ/y)

D*D

Summary (XYZ) cont’d• Y(3940)J/

– ( Y3940 J/) >7 MeV (huge!)

• “Y(4260)”+-J/– (y4260J/)>1.6 MeV

– JPC=1--, not seen in e+e- hadrons- no obvious D**D threshold distortions

• “Y(4325)”+-’– above allD**D thresholds

233 fb-1

conclusions• There seems to be a new hadron spectroscopy

in the 3.5~4.5 GeV mass region– Maybe more than one– Bodes well for BESIII, Super B factories & PANDA

• The new states are characterized by large partial widths (Bfs) to hadrons+J/

– Br(X(3872)J/) > 4.3% (Isospin=1)– (Y(3940)J/) > 7 MeV (SU(3) octet)– (Y(4260)J/) > 1.6 MeV

• There is no apparent transition at the D**D mass threshold

• The above-threshold 1-- charmonium state parameters listed in the PDG are probably not reliable

(mine)

Expect lots of results from Belle

this summer

謝謝

Look at e+e-J/ D(D(*))

•Reconstruct a J/ & a D•use D0K-+ & D+K-++

•Determine recoil mass

Inclusive BKx from BaBar

?

Fully reconstructed B- tags

Braaten et al: XD D*0 mass spectrumTheoretical prediction for a loosely bound D D* state.

BaBar looked for a charged partner of the X(3872) and excluded isospin 1: BF(B0 X- K+ ) BF(X J/ψ - 0 ) < 5.4 x 10-6

BF(B- X- K0 ) BF(X J/ψ - 0 ) < 2.2 x 10-5

c.f BF(B0 X0 K+ ) BF(X 0 J/ψ -- + ) =(1.28 0.41 ) x 10-5

Comments on the D0D00 mass peak

Fitted M: 3875.4 0.7 0.8 MeV+0.3-1.6

M–(mD0+ mD*0) = +4.3 0.7 MeV+0.3-1.6

2xPDG06 error on mD0

(could be 2.0 MeV)

PDG MX3872: 3871.2 0.5 MeV

Here error onmD0 drops out

Nominally ~2.3above D0D*0 threshold(but errors are non-Gaussian)

~2 discrepancy

DD* “Binding Energy?”:

Y(4260) at Belle

MX

Select e+e- ℓ+ℓ- +X; Nchg=4

Mℓ+ℓ-=MJ/30MeV; pJ/y>2 GeV; M>0.4GeV

| data4.2<MJ/<4.4

MC

M=4295 10 +11 MeV

= 133 26 +13 MeV -6

-5

For ’J/ in the same data:

M(’) = 3685.3 0.1 MeV(PDG: M(’)=3686.09 0.04)

M

Another one from BaBar?(4352)’ (produced via radiative return)