New Resonances a t Belle Jolanta Brodzicka INP Kraków For the Belle Collaboration

New Resonances New Resonances aat Bellet Belle

Jolanta BrodzickaJolanta BrodzickaINP KrakówINP Kraków

For the Belle For the Belle Collaboration Collaboration

XLXLIV Cracow SchoolIV Cracow School of Theoretical Physic of Theoretical Physicss,, ZakopaneZakopaneMay 28 - May 28 - June June 66, , 20042004

TopicsTopics : :• heavy-light mesons heavy-light mesons

• cs : Dcs : DSJSJ in e in e+ + ee-- cc continuum and B cc continuum and B exclusive decaysexclusive decays

• cu : D** in B cu : D** in B D D((**) ) + + - - decaysdecays

• charmonium-like state X(3872)charmonium-like state X(3872)

Jolanta BrodzickaJolanta Brodzicka, , INP INP

KrakówKraków

The Belle Collaboration The Belle Collaboration

A World-Wide Activity: A World-Wide Activity: ~300 People from ~50 Institiutions~300 People from ~50 Institiutions

, Belle , Belle CollColl..

KEK-B FactoryKEK-B Factory

Jolanta BrodzickaJolanta Brodzicka, , INP INP KrakówKraków

KEKB : Asymmetric eKEKB : Asymmetric e++ee--

collidercollider•Two separate ringsTwo separate rings

ee++ ( (LERLER) : 3.5 GeV) : 3.5 GeV

ee-- ( (HERHER) : 8.0 GeV) : 8.0 GeV• CM energy : 10.580 GeV at CM energy : 10.580 GeV at

(4S) (4S)

e+e- e+e- (4S) BB BB • Parameters Parameters

•3016 m circumference3016 m circumference•±11 mrad crossing angle ±11 mrad crossing angle

• History: Physics run since June History: Physics run since June

19991999

• Luminosity Luminosity peakpeak:: 1.31.3x10x103434

cmcm-2-2ss-1-1

(achieved: (achieved:

20May200420May2004))

• Integrated LuminosityIntegrated Luminosity: : 250 250

fbfb-1-1

~ 260 x 10~ 260 x 10 6 6 BB BB

~ 300 x 10~ 300 x 10 6 6 cc cc

continuum eventscontinuum events


Particle identificationParticle identification K/ separation

CDC : dE/dx Aerogel Cherenkov Counter (ACC) Time of Flight Counter (TOF)

electron identification ECL

KL and identification KL and muon detector (KLM)

VertexingVertexing SVD

Belle Detector Belle Detector


Event reconstructionEvent reconstruction Charged track Central Drift Chamber (CDC)

Silicon Vertex Detector (SVD) Electron and photon Electromagnetic Calorimeter (ECL)


Silicon Vertex Detector

KL / Detector

SC Solenoid 1.5T

Central Drift Chamber

Aerogel Cherenkov Counter

Electromagnetic Calorimeter

Time of Flight Counter

Topic of this

talk

• BaBarBaBar with with 91 fb-1 on/off (4S) discovered resonancediscovered resonance DDSJSJ(2317) (2317) D DSS

±± 0 0

• isospin violating decay , narrow state isospin violating decay , narrow state ( ( < 10MeV ) < 10MeV )

• BaBarBaBar also also ssawaw peak peak in in DDS S 00 mass distribution mass distribution @ @ ~2460 2460 MeVMeV

Interpreted as cInterpreted as cross-feed from 2317ross-feed from 2317 ((DDSS from 2317 + random from 2317 + random ) )

• CLEO CLEO ((13.5 fb-1)) confirmed confirmed DDSJSJ(2317) (2317) establishedestablished DDSJSJ(2463)(2463) D DS S **±±

0 0

• BelleBelle ((87 fb-1)) saw both : DDSJSJ(2317) D(2317) DSJSJ(2457) (2457) states in cc continuum

& in B decays


NNew observationsew observations at B at B--FactoriesFactories


DDSJSJ(2317) D(2317) DSJSJ(2457)(2457) identified with :identified with : 00++ , 1 , 1++ orbitally orbitally excited P-wave cs statesexcited P-wave cs statesInconsistentInconsistent with model predictions. with model predictions.

Expected:Expected: broad states with masses: 2.48 2.53 GeV (above D broad states with masses: 2.48 2.53 GeV (above D((**))K threshold)K threshold)

InterpretatioInterpretations:ns:

more exotic assignments :more exotic assignments : DK molecule, multiquark DK molecule, multiquark state, mixing P-wave cs states with 4-quark csqq state, mixing P-wave cs states with 4-quark csqq

states (states ( masses shifted below masses shifted below DD((**))KK ))

Potential Model for Q q Potential Model for Q q Godfrey-IsgurGodfrey-Isgur (1985)

QQ

qq


qSLqj

QSqjJ Total spin of a

meson

Angular momentum of the light quark

Inter-quark potential : Inter-quark potential :

Basic hypothesBasic hypothesees s of of constituent quark model : constituent quark model : • mesons : valence-quark configurationmesons : valence-quark configuration• dynamics described by a Hamiltonian:dynamics described by a Hamiltonian:

• relativizedrelativized• confinement with running confinement with running s s • one gluon exchange dominates at short distanceone gluon exchange dominates at short distance

VQq Hconf + Hspin-spin (color-hyperfine) + Hspin-

orbit (1-gluon-exch)

+ Hspin-orbit (Thomas precession)

Q Q at rest at rest (no chromomagnetic field, static source of (no chromomagnetic field, static source of chromoelectric field)chromoelectric field) , Q decouples from q , Q decouples from q

dynamics of the q dynamics of the q meson properties meson properties

Heavy Quark Symmetry:Heavy Quark Symmetry: mmQ Q

(~hydrogen atom)(~hydrogen atom)

separately conservedseparately conserved


Predictions for cu and cs mesonsPredictions for cu and cs mesons


• L = 1 Parity+• jq= ³/2 J =2

J = 1

• jq= ½ J = 1

J = 0• L = 0 Parity -

• jq = ½ J= 1

J= 0

D*D*22 (2462)(2462)DD1 1 (2421) (2421) D’D’1 1 2.44 GeV

D*D*0 0 2.40 GeV

DDSJSJ(2573)(2573) DDS1S1(2536)(2536) D’D’S1 S1 2.53 GeV

DDS S 00 2.48 GeV

Ds* (2112) Ds (1968)

D* (2007) D (1865)

uc sc

• P-wave states with jq= ½ : expected to be broad (S-wave decays)) difficult to identify experimentally (jq= ³/2 states: narrow)• Also some predictions that: m( jq= ½ ) > m(jq= ³/2 )

based on Heavy Quark Symmetry based on Heavy Quark Symmetry

Missing Missing doublets doublets

till last till last summersummer

spin-orbit spin-orbit relativistic correction to relativistic correction to HQ S : HQ S : an expansion in powers of an expansion in powers of

11//mmQQ

spin-spin spin-spin hyperfine splittinghyperfine splitting



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DDSJSJ((23172317) @ Belle ) @ Belle

M(M(DDSJSJ(2317)(2317)) = 2317.2 ± 0.5) = 2317.2 ± 0.5 (stat) ± 0.9(stat) ± 0.9 (syst) MeV/c (syst) MeV/c 22

< 4.6 MeV< 4.6 MeV/c /c 2 2 ((90% C.L90% C.L.).)

• data sampledata sample: : 87 fb 87 fb-1-1 • e+e- e+e- cc cc D Dss

± 0 0 X X (inclusively-produced)(inclusively-produced)

• DDss ±± ((KK- - KK++ ))±± p* (p* (DDs s

±± 00 ) > ) > 3.5 GeV 3.5 GeV (p in CMS)(p in CMS) (to reduce

combinatorial background)

0 /DS±

sidebands

M( DM( DS S 0 0 ) - M( D) - M( DS S ) GeV/c ) GeV/c 22

Eve

nts

/5M

eV DK thresholdDK threshold Fitted signal:Fitted signal: 761 761 44 44 (stat)(stat) 30 30 (syst)(syst)

M( M( DDS S 00 ) - M( ) - M( DDS S ) GeV/c ) GeV/c 22

Small peak : feed-down from DDSJSJ(2457)



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DDSJSJ((24572457) @ Belle ) @ Belle

M( DM( D**S S 0 0 ) - M( D) - M( D**S S ) GeV/c ) GeV/c 22M( M( DD**

S S 00 ) - M( ) - M( DD**S S ) GeV/c ) GeV/c 22

Eve

nts

/5M

eV

• e+e- e+e- cc cc D Dss**± 0 0 X X ( D( Dss**

± 00 inclusively inclusively produced )produced )• DDss**

± D Dss±± DDss

±± ((KK- - KK++ ))+ + p* (p* (DDss**±±

00 ) > ) > 3.5 3.5 GeVGeV

„Peaking” background sources:• Signal feeddown from DSJ(2317)+ random soft •„Broken” DSJ(2457) signal : Ds* with „bad”

Fitted signal:Fitted signal:126126 2525 (stat)(stat) 12 12 (syst)(syst)

M(M(DDSJSJ(2457)(2457)) = 2456.5 ± 1.3(stat) ± 1.3(syst) MeV/c ) = 2456.5 ± 1.3(stat) ± 1.3(syst) MeV/c 22

< 5.5 MeV< 5.5 MeV/c /c 2 2 (90% C.L.)(90% C.L.)

DS* ±

sideband

Sideband-subtracted distribution

Test of nature ofTest of nature of DDSJ SJ :: search for other search for other decay modes decay modes , Belle , Belle CollColl..

59 59 11 11


Decay modes ofDecay modes of DDSJSJ

M( M( DDS S ++ -- ) - M( ) - M( DDS S ) GeV/c ) GeV/c 22M( M( DDS S ) - M( ) - M( DDS S ) GeV/c ) GeV/c 22

Eve

nts

/3M

eV

Eve

nts

/5M

eV

DDSJSJ(2457) (2457) D DSS± + + --

152 152 18 18

DDSJSJ(2457) (2457) D DSS±

BR( DBR( DSJSJ(2457) (2457) D DSS± ))

BR( DBR( DSJSJ(2457) (2457) D Dss**± 0 0 ))

= 0.55 ± 0.13(stat) ± 0.08(syst)= 0.55 ± 0.13(stat) ± 0.08(syst)

• No signal observed in:No signal observed in: DDSJSJ(2457) (2457) DDss**

± , D, Dss± 00

DDSJSJ(2317) (2317) DDss± , D, Dss**

± , D, DSS±

+ + - -

DDSJSJ(2457)(2457) : : JJPP 00+ + ,,00- - favours favours J JPP= 1= 1+ +

DDSJSJ(2317)(2317) : : favours favours J JPP= 0= 0+ +

From From cconservation of onservation of angular mom. and parity angular mom. and parity

DDSS1 1 (2(2536536))DDSJSJ(2317) region(2317) region

Dipion Dipion mode mode

11stst timetime observedobserved

((D’D’S1S1 assumption: 0.62 )assumption: 0.62 ) ((D’D’S1S1 assumption: 0.16 )assumption: 0.16 )Godfrey,Phys.Lett.B 568, 254 (2003)Godfrey,Phys.Lett.B 568, 254 (2003)


BR( DBR( DSJSJ(2457) (2457) D DSS± + + - - ))

BR( DBR( DSJSJ(2457) (2457) D Dss**± 0 0 ))

= 0.14 ± 0.04(stat) ± 0.02(syst)= 0.14 ± 0.04(stat) ± 0.02(syst)


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DDSJ SJ in cc continuum - in cc continuum - summarysummary

• Belle Belle observed observed DDSJSJ(2317)(2317) D DSS±±

0 0

and and DDSJSJ(2457)(2457) DDS S **±± 0 0

inclusively produced in e+e- inclusively produced in e+e- cc continuum cc continuum

• radiative and dipion decay modes of radiative and dipion decay modes of DDSJSJ(2457)(2457)

observedobserved • the spin-parities the spin-parities 00++ ((DDSJSJ(2317)(2317)) ) and and 11++ ((DDSJSJ(2457)(2457)) ) are are

favoured favoured


--

• Assignments ofAssignments of DDSJSJ(2317)(2317) andand DDSJSJ(2457)(2457) being being orbitally excited cs mesonsorbitally excited cs mesons need confirmation need confirmation

• IfIf DDSJSJ(2317)(2317) andand DDSJSJ(2457)(2457) areare cs cs states states : : can be observed incan be observed in BB D D DDsJsJ decaysdecays

expectedexpected BF ~ 10 BF ~ 10-2-2 10 10-3-3 , quite large , quite large

• States States cs with jcs with j q q= ½= ½ “easier” produced in B decays than those with jeasier” produced in B decays than those with j q q= ³/= ³/2 2 (HQET) (HQET)

• States produceStates producedd in B decay can be polarized: from angular distributions in B decay can be polarized: from angular distributions J J PP

• In B decays : background reductionIn B decays : background reduction

DDSJSJ iin B exclusive decays n B exclusive decays


Motivations: Motivations:


Tree type diagramprocesses

Kinematical Variables:Kinematical Variables:

•Energy differenceEnergy difference

•Beam-constrained Beam-constrained mass mass


KKinematical constraints are usedinematical constraints are used

beam*

n

i

i* EEΔE

2n

i

i*2

beam*

bc PEM

• For B decay to specific final state: For B decay to specific final state: B B f f 1 1 f f 2 2 …… f f nn

B*

n

i

i* EE B

*n

i

i* PP

MeV300P B* beam

*B

* EE

• Experimental conditions:

Method of full B Method of full B reconstructionreconstruction

e+e- e+e- (4S) BB m BB m (mB+mB)

In (4S) frame Energy-Momentum conservation:


resolution resolution improvement, improvement, background background separationseparation


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BB D D DDsJsJ decays decays

Reconstructed modes:Reconstructed modes: BB0 0 DD- - DDsJsJ++B+ B+ DD00 D DsJsJ

++

0π

sD)2317(sJD)2317(sJDD B

0π

*

sD)2457(sJD)2457(sJDD B

s

D)2457(sJD)2457(sJDD B

M( M( DDSJ SJ ) GeV/c ) GeV/c 22E GeVE GeV

Eve

nts

/10M

eVBoth isospin related modesBoth isospin related modes

data sampledata sample: : 115115 fb fb-1-1


Signal extracted in E, Mbc and M(DSJ)

Plot one of them with cuts on the others

DDSS± ddecayecay angle of angle of

in in DDSJSJ (2457) (2457) D DSS± ( (B B D D D DSJ SJ ))

J=1 J=1 hypothehypothesissis

J=2J=2 hypothehypothesissis

DDSJSJ iin exclusive B decays – n exclusive B decays – summary summary


• first observation first observation of of DDSJSJ states in B decay states in B decay in Bellein Belle• no new Dno new DSJSJ decay modes decay modes in comparison to inclusive production in comparison to inclusive production • masses and widths consistent masses and widths consistent • DDSJSJ (2457) (2457) angular analysis consistent with angular analysis consistent with J=1J=1• measured measured BR’s do not exclude cs statesBR’s do not exclude cs states assignments assignments


BR(BBR(BDDDDSJSJ) ) BR( BR(DDSJSJ) comparison:) comparison:

BR(DDBR(DDSJSJ)xBR( D)xBR( DSJSJ(2457) (2457) D DSS± ))

BR(DDBR(DDSJSJ)xBR( D)xBR( DSJSJ(2457) (2457) D Dss**± 0 0 )) 0.0.44


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New DNew D****00 states states

• data sampledata sample : : 60 fb60 fb-1-1 • Dalitz analysis for :Dalitz analysis for :

BB+ DD- + + + + (~1100 signal events) (~1100 signal events) andand BB+ D*D*- + + + +

(~600 events)(~600 events)

• unbinned likelihood fit performedunbinned likelihood fit performed with with signal density signal density function:function:

S S (M (M 1122, M, M22

2 2 )) = = Ai exp(ii ) BWi (MM1 1 22, M, M2 2

22 ) + ) + Aexp(i ) 2 2 R(MR(M22))

both with good

S/B

expected decay modes: Dexpected decay modes: D- + , + , D*D*- ++


coherent sum of the amplitudes of D** states which can contribute and phase space termcoherent sum of the amplitudes of D** states which can contribute and phase space term convolution with experimental resolution convolution with experimental resolution


DD****00 mesons mesons Dalitz plot Dalitz plot

projections projections with with fit results fit results

First observationFirst observationof of D*D*0 0 and and DD11’’00

Background

Background

M ( M ( D D minmin ) ) GeV/c GeV/c 22 M ( M ( D D minmin

) ) GeV/c GeV/c 22

M ( M ( D* D* minmin ) ) GeV/c GeV/c 22 M ( M ( D* D* minmin

) ) GeV/c GeV/c 22



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DD****00 - summarysummary

• Belle observed for the first timeBelle observed for the first time broadbroad D*D*00 and and DD11’’00

states in B decaysstates in B decays

(observed also by FOCUS, (observed also by FOCUS, poor poor

agreement in measured massesagreement in measured masses))

• Identified as Identified as 00++ and and 11++ orbitally excited orbitally excited cu cu doublet doublet

(with(with jj q q= ½= ½ ))

• Narrow Narrow 11++ , , 22++ states: states: DD1100 and and DD22** 0 0 also seenalso seen

(already (already

observed by CLEO)observed by CLEO)

• Masses and widths of four D** states were Masses and widths of four D** states were

measured measured


Measured masses versus Measured masses versus model predictionsmodel predictions



• In In cucu spectrum: masses of D, D*,D** consistent with model expectations spectrum: masses of D, D*,D** consistent with model expectations • In In cscs case: masses of new case: masses of new DDSJSJ (2 (231317) 7) andand D DSJSJ (2457) (2457) inconsistent inconsistent

Nowak’s talk Nowak’s talk

Chiral symmetry broken Chiral symmetry broken chiral partners split off (chiral partners split off (states with opposite paritystates with opposite parity))

DDSJSJ (2 (231317) 7) andand D DSJSJ (2457) (2457) interpreted asinterpreted as chiral partners of chiral partners of DDS S andand D*D*S S ? ?

Model expectatiModel expectatioon:n:M(M(cscs ) – M( ) – M(cucu) ) 100 MeV 100 MeV

DDiiscoveryscovery of of X(3872)X(3872)


• Belle Belle data sampledata sample: : 140 fb 140 fb-1-1 • in B decayin B decay B B ± K K± + + -- J/ J/ J/J/ l l+ + ll--

For B signal For B signal extracted in extracted in E, ME, Mbcbc

New state is not New state is not reflection from reflection from any known stateany known state

M( M( + + - - ll+ + ll- - ) - M() - M( ll+ + ll- - ) GeV ) GeV M( M( + + - - ll+ + l l - - ) - M() - M( ll+ + l l - - ) )

new narrow charmonium-like state : new narrow charmonium-like state : X(3872) X(3872) J/ J/ + + --


X(3872)X(3872)


Eve

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eV

Eve

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eV

Eve

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eV

E GeVE GeVMbc GeVMbc GeV M ( J/M ( J/ + + - - ) GeV ) GeV

• Signal Signal B B ±± X(3872)KX(3872)K± ± extracted in extracted in E, ME, Mbcbc and and M( J/M( J/ + + -- ))• Plot one of them with cut on the othersPlot one of them with cut on the others • Simultaneous fit Simultaneous fit in 3 variables in 3 variables

MMXX = 3872.0 ± 0.6(stat) ± 0.5(syst) MeV = 3872.0 ± 0.6(stat) ± 0.5(syst) MeV XX < 2.3 MeV < 2.3 MeV ((90% C.L.90% C.L.))

S = 35.7S = 35.7 6.8 6.8 (10(10 ) )

• MMX X > M(D + D> M(D + D )) open-charm decay possible, open-charm decay possible, why so narrowwhy so narrow ? ? • X produced in B decays: J cannot be high X produced in B decays: J cannot be high • Is it Is it charmoniumcharmonium state? state? • One of the unobserved higher charmonium states One of the unobserved higher charmonium states 1133DDJJ 1111DD2 2 2233PP1 1 2211PP11 ??

(predicted masses @ X mass region)(predicted masses @ X mass region)• MMX X M(D M(D00 + D* + D*00 ) ) loosely boundedloosely bounded molecular or hybrid state? molecular or hybrid state? , Belle , Belle CollColl..


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Properties of X(3872) Properties of X(3872)

• B B ±± K K± ± c1c1 c1c1(1P) (1P) J/ J/

• B B ±± K K± ± c2 c2 c2c2(1P) (1P) J/ J/

33DDc 2c 2 3 3DDc 3c 3 ?? X(X(38723872) ) cc11 , ,

cc22

Eve

nts

/4M

eV

Eve

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/8M

eV

Eve

nts

/5M

eV

Eve

nts

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eV

Mbc GeVMbc GeV

Mbc GeVMbc GeV

M (M ( c1c1 ) GeV ) GeV

M (M ( c2c2 ) GeV ) GeV

No signal in No signal in X(3872) regionX(3872) region

(( X(X(38723872) ) cc11 ))

(( X(X(38723872) ) J/J/ + + - - )) 0.89 0.89 ((90% C.L.90% C.L.))

(( X(X(38723872) ) cc22))

(( X(X(38723872) ) J/J/ + + - - )) 1.11.1 ((90% C.L.90% C.L.))

33DDc 2 c 2 && 33DDc 3 c 3 ruled outruled out

2. 2. ((33DDc 2c 2 cc11 ) )

((33DDc 2c 2 J/J/ + + - - ))Theory:Theory:


• Checking hypothesis that X(3872) is charmonium state Checking hypothesis that X(3872) is charmonium state radiative X decays should be observed radiative X decays should be observed (Eichten,Lane,Quigg)(Eichten,Lane,Quigg)

Properties of X(3872) Properties of X(3872)


2233PP11 ?? X(X(38723872) ) J/J/ ( ( 2233PP11 J/J/ ) )

( ( 2233PP11 J/J/ + + - - )) 11keV 11keV // 0.3keV 0.3keV 30 30 TheorTheor

y:y:

’’c1 c1 (( 2233PP1 1 )) ruled outruled out

M (M ( J/J/ ) - M () - M ( J/J/ ) GeV ) GeV

B B ±± K K± ± J/J/

Absence of Absence of X(3872) X(3872)

h’h’c c (( 2211PP1 1 ) ? ) ?

cos cos (J/(J/ ))

X(3872) X(3872) J/ J/ + + -- ((B B K X(3872) K X(3872) ) )

J/J/ ddecay ecay angle angle in in

Prediction for 1Prediction for 1+ + : : 1- cos1- cos22 (J/ (J/ ))

h’h’c1 c1 (( 2211PP1 1 )) ruled outruled out, Belle , Belle CollColl..


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X(3872) – summary X(3872) – summary

• New unexpected New unexpected state state X(3872) X(3872) observed by Belleobserved by Belle

(also seen at Fermilab in (also seen at Fermilab in

pp collisions and BaBar )pp collisions and BaBar )

• Still no obvious charmonium assignmentStill no obvious charmonium assignment

• Is it Is it DD0 0 D*D*00 molecule? molecule?


MMXX = 3872.0 ± 0.6(stat) ± 0.5(syst) MeV = 3872.0 ± 0.6(stat) ± 0.5(syst) MeV

XX < 2.3 MeV < 2.3 MeV ((90% C.L.90% C.L.))

Summary Summary


• Many charm results from Many charm results from BelleBelle..

Some of them Some of them

unexpected or/and inconsistentunexpected or/and inconsistent with theoretical with theoretical

expectations.expectations.

• B-Factory is a Charm Factory, too. B-Factory is a Charm Factory, too.

In aditionIn adition B decays B decays areare good and clear ground good and clear ground

to study charm spectroscopy.to study charm spectroscopy.



KrakówKraków, Belle , Belle CollColl..

DD mesonsmesons DDss mesons mesons

L=1L=1L=1L=1




KrakówKraków, Belle , Belle CollColl..

New Resonances a t Belle Jolanta Brodzicka INP Kraków For the Belle Collaboration

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