Tomi Živko. Belle Collaboration

Transcription

1 Hadronic spectroscopy at Belle Tomi Živko J. Stefan Institute, Ljubljana, Slovenia Belle Collaboration Bled Workshop 2009, Bled, Slovenia 29th June 6th July 2009

2 List of topics Experimental set-up and tools DsJ states Charmonium and charmonium-like states Summary and conclusions 2

3 Experimental set-up & tools The accelerator... 日本 Belle... an asymmetric-energy factory of B mesons e+ (4S) p(e+) = 3.5 GeV/c 茨城県 diameter ~ 1km ep(e ) = 8.0 GeV/c (4S): bound state of bb; (JPC = 1- -, radially excited); above the threshold for BB decays B (bu, bd) つくば 東京 Centre-of-mass energy: s = M(Y(4S)) c2 ~ 10.58GeV (4S) B (bu, bd) 3

4 Experimental set-up & tools (integrated) Luminosity # of events Resonance N = ℒ dt cross-section Continuum Daily! BB pairs: on (4S) resonance: 1fb-1~1.1M BB Other processes (continuum): u,d,s,c e+ γ* e- u,d,s,c 4

5 Experimental set-up & tools (integrated) Luminosity # of events N = ℒ dt Resonance cross-section Continuum Daily! BB pairs: on (4S) resonance: 1fb-1~1.1M BB Approaching 1 ab! ~ 0.8 x 109 BB pairs -1 Other processes (continuum): u,d,s,c e+ γ* e- u,d,s,c 5

6 Experimental set-up & tools (integrated) Luminosity # of events Resonance ch -fa ar ct o m ri e ( fa ch s a ct a r r e or m ie on als s! iu o m ) N = ℒ dt cross-section Continuum Daily! B BB pairs: on (4S) resonance: 1fb-1~1.1M BB Approaching 1 ab! ~ 0.8 x 109 BB pairs ~ 1.2 x 109 cc pairs -1 Other processes (continuum): u,d,s,c e+ γ* e- u,d,s,c 6

7 The Belle detector Long-life particles we detect: e±, ±, ±, K±, p, µ and KL detection system Decaying particles we reconstruct: B±, B0, D±, D0, 0, 0,... Aerogel Cherenkov Counter (n = ) (14/15 layers RPC+Fe) 3.5 GeV e+ Silicon Vertex Detector (3/4 layers DSSD) Electromagnetic Calorimeter (CsI crystals; 16X0) 8 GeV e Central Drift Chamber (small cells, He/C2H6; σp/p ~0.35%) ToF Counter Superconducting Solenoid (B = 1.5 T) 6

8 The Belle collaboration 8

9 Charmed strange mesons (DsJ states) 8

10 Charmed strange mesons (overview) BABAR : 91 fb-1 PRL 90, (2003) DsJ (2317) and DsJ(2460) first CLEO : 13.5 fb observed by BABAR and CLEO PRD 68, (2003) in inclusive cc continuum events Belle : 124M BB PRL 91, (2003) and by Belle also in B-decays Belle : 87 fb PRL 92, (2004) Both masses unexpectedly low: below D*K and DK threshold, respectively Only isospin-violating or electromagnetic decays kinematically allowed narrow widths * HQET: jq good Q# -1-1 j Decay patterns and angular distributions now well established as: Belle : 274M BB P-wave cs mesons BELLE-CONF-0461 (2004) with JP=0+ and JP=1+,respectively Belle : 152M BB PRL 94, (2005) More B-decay production modes: B0 DsJ- K+ (besides B0 DDsJ) Belle : 386M BB hep-ex/

11 DsJ*(2700)+ observed in B+ D0 D0 K+ New cs state: B+ D0 DsJ(2700)+, DsJ(2700)+ D0 K+ PRL PRL100, 100,092001(2008) (2008) BB BB veto D0 ψ(3770) fit region θ DsJ B+ D0 K+ spin assignment DsJ(2700)+ 182±30 events (8.4 σ) Dalitz plot illustrates the features, while background-subtracted distributions are fitted Ψ(3770) D0 D0 veto applied B+ K+ Ψ(4160) contribution, phase-space and threshold taken into account Signal yield is efficiency corrected 11

12 DsJ*(2700)+ in B+ D0 D0 K+ cont'd PRL PRL100, 100,092001(2008) (2008) BB BB agrees with WA DsJ(2700)+ threshold Ψ(3770) Ψ(4160) phase-space J=1 J=0 J=2 hel. & : JP=1- favoured 12

13 DsJ(2700)+ D0K+: Preferred: JP=1 Mass (GeV/c2) DsJ meson spectroscopy update Possible interpretations: Radially excited 23S1 (excited Ds*) with mass ~2720 MeV/c2 { Godfrey et al. PRD 32, 189 (1985); Close et al., PLB 647, 159 (2007) } Chiral doublet 1 state to 1+ Ds1(2536)+ with mass (2721 ± 10) MeV/c2 { Nowak et al., Acta Phys. Pol. B 35, 2377(2004) } Confirmation needed: Is it X(2690) seen by BaBar? (Compatible M,Γ; DK decay mode) 14

14 DsJ(2700)+ D0K+: Preferred: JP=1 Possible interpretations: Radially excited 23S1 (excited Ds*) with mass ~2720 MeV/c2 { Godfrey et al. PRD 32, 189 (1985); Close et al., PLB 647, 159 (2007) } Chiral doublet 1 state to 1+ Ds1(2536)+ with mass (2721 ± 10) MeV/c2 { Nowak et al., Acta Phys. Pol. B 35, 2377(2004) } Confirmation needed: Is it X(2690) seen by BaBar? {BaBar, PRL 97, (2006)} Mass (GeV/c2) DsJ meson spectroscopy update DsJ(2860)+ D0K+: Yet another new state from BaBar: Radial excitation of Ds0(2317)+? 14

15 Ds1(2536)+ D+π-K+, D*+KS0 PRD PRD77, 77, (2008) (2008) fb fb-1 Another result of the renewed interest in measurements of charm mesons after DsJ*(2317) & DsJ(2460)... First observation of: Ds1(2536)+ D+π-K+(in e+e- Ds1(2536)+X) - no D*0 { M(D*0) < M(D+)+M(π-) } - only 2nd three-body decay mode of Ds1(2536)+after Ds+ π+ π- D+π-K+ mode 1281±66 signal evts Also: Ds1(2536)+ D*+KS0 very clean and large sample improves PID efficiency for K±&π± and removes Ds1(2536)+ from B's D*+KS0 mode 5673±81 signal evts fast Ds1(2536)+ : xp=p*/p*max>0.8 15

16 Ds1(2536)+ D+π-K+, D*+KS0 PRD PRD77, 77, (2008) (2008) fb fb-1 Another result of the renewed interest in measurements of charm mesons after DsJ*(2317) & DsJ(2460)... First observation of: Ds1(2536)+ D+π-K+(in e+e- Ds1(2536)+X) - no D*0 { M(D*0) < M(D+)+M(π-) } - only 2nd three-body decay mode of Ds1(2536)+after Ds+ π+ π- D+π-K+ mode 1281±66 signal evts Also: Ds1(2536)+ D*+KS0 very clean and large sample partial wave analysis (PWA) D*+KS0 mode 5673±81 signal evts 16

17 Ds1(2536)+ D+π-K+, D*+KS0 PRD PRD77, 77, (2008) (2008) fb fb-1 Another result of the renewed interest in measurements of charm mesons after DsJ*(2317) & DsJ(2460)... First observation of: Ds1(2536)+ D+π-K+(in e+e- Ds1(2536)+X) - no D*0 { M(D*0) < M(D+)+M(π-) } - only 2nd three-body decay mode of Ds1(2536)+after Ds+ π+ π- D+π-K+ mode 1281±66 signal evts Also: Ds1(2536)+ D*+KS0 very clean and large sample partial wave analysis (PWA) Motivation: D*+KS0 mode 5673±81 signal evts HQET exact: D(S)-wave for jq=3/2 (1/2) HQET not exact: Ds1(2536)+ contains small admixture of jq=1/2 17

18 Ds1(2536)+ D*+KS0 : PWA PRD PRD77, 77, (2008) (2008) fb D (2536)+ is produced in e+e- D (2536)+X with small polarization 462 fb s1 s1 3D angular fit performed (,, ) (e+e- CMS ) D*+ rest frame Ds1(2536)+ rest frame ΓS / Γtotal= 1/(1 + D/S 2 )= bckg subtracted, eff. corrected and normalized distributions 0.72 ± 0.05 ± 0.01 S-wave dominates in Ds1(2536)+ D*+ KS0 decay (unlike HQET expectation for pure jq=3/2; projections of the 3D fit Ds1(2536)+ - Ds1(2460)+ mixing?) However: Small energy release D-wave suppressed even small S-wave component increases Γ 18

19 Charmonium(-like) states 19

20 cc[-like] production at B-factories Colour-suppressed B decays: e.g. B Xcc K(*) b B e+ e+ V *c b W Two-photon production: e+e- e+e- * * e+e-xcc c c V cs u,d X cc s K u,d c J/ c e- e- 0- +, 0+ +, 2+ + e+e- radiative return (ISR): e.g. e+e- ISR Xcc ISR e - ISR * e+ * c c Xcc states with C=+ Xcc * * 0- +, 1- -, 1+ + Double cc production: e.g. e+e- J/ Xcc e- * Xcc e only 20

21 Standard Charmonium States n(2s+1)lj cc c c n radial quantum number S total quark-antiquark spin L relative orbital ang. mom. (L = 0, 1, 2... S,P,D states) c" (3S) c0' c1' hc' c2' c2 " ' c' hc c0 J/ c c1 2 3 J=S+L P = ( 1)L+1 parity C = ( 1)L+S charge conjugation MD+MD*= MeV/c2 open-charm threshold 2MD c2 Below the DD threshold: black: measurements blue: predictions States are narrow All states observed well measured recently observed 21

22 Standard Charmonium States n(2s+1)lj ( cc ) 0) 6 c" ( 4 1 (3S) 0 ) ' c1' 4 ' ' 0 c0 4 2 c2 ( c 2 hc' 7 3 ( c' 0) 7 " hc c2 ' c0 J/ c c1 c c n radial quantum number S total quark-antiquark spin L relative orbital ang. mom. (L = 0, 1, 2... S,P,D states) 3 J=S+L P = ( 1)L+1 parity C = ( 1)L+S charge conjugation MD+MD*= MeV/c2 open-charm threshold 2MD c2 Above the DD threshold: black: measurements blue: predictions States expected to be wide Only five states measured and identified Many candidates available 22

23 Exotic Charmonium-like States Multiquark states Molecular states c π c u Exotic states: Are not forbidden in SM; Have exotic JPC (0+-, 1-+, 2+-,... forbidden for qq); Tetraquarks u c exotic decay modes Tightly bound diquark-diantiquark states c u (not possible for qq); strange properties (widths,...); c Charmonium hybrid states Multiquark states could also have c States with excited gluonic degrees of freedom g non-zero charge [cucd], strangeness [cdcs] Hadro-Charmonium or both [cucs] Compact charmonium states bound inside light hadronic matter Loosely bound pair of charm mesons u (q,g/pion exchange at short/long distances) Threshold-effects Virtual states at the threshold Charmonium states with shifted masses due to nearby D(*)D(*) thresholds Mixture of the above or something even more exotic? 23

24 and many candidates (X, Y, Z) S. L. PANIC 2008, Eilat, Israel, 9-14 Nov, 2008 (arxiv: v1[hep-ex]) 24

25 and many candidates (X, Y, Z) Only some of these states will be mentioned. S. L. PANIC 2008, Eilat, Israel, 9-14 Nov, 2008 (arxiv: v1[hep-ex]) 25

26 The good old X(3872): discovery Observed first by Belle in 2003: X(3872) ± ± + B K J/ψ = (2S) ℓ+ ℓ- (34 ± 7) events (~10 ) M=( ± 0.6 ± 0.5) MeV/c2 X(3872) BR(B- XK-)xBR(X J/ψ π+π-) = (1.3 ± 0.3)x10-5 Confirmed soon by: PRL 93, (2004) Belle : 152M BB PRL 91, (2003) b W Bu c c s u ' K- M( + - ℓ+ ℓ-)- M(ℓ+ ℓ-) PRL 93, (2004) PRD71,071103R(2005) PRD73,011101R(2006) 26

27 X(3872): properties PDG2008 mass: MX = ( ± 0.8) MeV/c2 hep-ex/ (close to D0D*0 threshold:mx M(D0D*0) <1MeV/c2) Narrow: Γ < 2.3 MeV (@ 90% CL) From M(π+π-): clustering on high end X(3872) J/ψ ρ (S or P wave) (J = 1 or 2) PRL96,102002(2006) Decay modes: - X(3872) J/ψγ (establishes C=+1) PRL 102, (2009) 3.6σ hep-ex/ ±4.4 (4σ) M(π+π-)) [GeV] 256fb-1 B+ X K+ small Br X γj /ψ =0.14±0. 05 Br X π π J /ψ 424fb-1 - comparable rate J/ψω and J/ψρ (large isospin breaking unlike charmonium) - DDπ (but no DD) favoured JPC = 1++ or

28 X(3872): interpretation No standard charmonium assignment... Other possible (popular) interpretations: [ cu ][ cu ] or [ cd ][ cd ] tetraquark: - Requires different X mass in B+ and B0 decays. - Charged X[ cu ][ cd ] is expected. { Maiani et al., PRD 71, (2005) ; Ebert et al. } c u Xu = u c c d Xd = d c D*0D0 molecule: - MX ~ m(d0) + m(d*0) - Isospin breaking expected - Favours DDπ over J/ψππ - JPC = 1++ (D0D*0 in S-wave) - Production in B0 suppressed wrt. B+ { Braaten et al., hep-ph/ } 28

29 X(3872): Searches for partners? Are there X(3872) production differences in BR's, depending on B charge? Are the produced X's different? c u Xu = u c c d Xd = d c X(3872) J/ψπ+π PRD77,111101,2008 B+ XK+ B XK σ diquark-antidiquark models Xu and Xd from B0 and B+ decays MX= 8±3 MeV {Maiani et al PRD71, } MX = (2.7 ± 1.6 ± 0.4 ) MeV/c2 MX = (0.18±0.89±0.26 ) MeV/c2 12.8σ 8.6σ B0 XK0s ArXiv: ΔM~0 : Not really supported by the 4-q hypothesis B0 XK0s 6.5σ Br(B0 XK0) / Br(B+ XK+) = 0.41 ± 0.24 ± ± 0.22 ± 0.05 R~1: Not really supported by the molecular interpretation 29

30 X(3872): D0D0π0 decay mode Belle : 447M BB PRL 97, (2006) B+ K+D0D0π 0/ B0 K0D0D0π 0 PRD77,011102,2008 ( 6. 4σ ) B+& B0 D0D*0K 4.9σ 347fb-1 B K D0D*0 D* D0π0 D* Dγ te a d p U ArXiv: New Belle vs New BaBar only ~2σ difference 605 fb-1 PDG Flatte vs BW similar result: 8.8σ 2 states X(3875) & X(3872)? Tetraquark interpretation {Maiani et al., hep-ph/ }: Xu D0D0π 0 (X(3875)) ; Xd J/ψπ + π (X(3872)) 30

31 X(3872): D0D0π0 decay mode Belle : 447M BB PRL 97, (2006) B+ K+D0D0π 0/ B0 K0D0D0π 0 PRD77,011102,2008 ( 6. 4σ ) B+& B0 D0D*0K 4.9σ 347fb-1 B K D0D*0 D* Dγ Tetraquark hypothesis not favoured. New Belle vs New BaBar only ~2σ difference e t Purely damolecular hypothesis not favoured. D* D0π0 p U ArXiv: fb-1 Favoured: Mixture of D0D*0 molecule and ccbar state. PDG Flatte vs BW similar result: 8.8σ 2 states X(3875) & X(3872)? Tetraquark interpretation {Maiani et al., hep-ph/ }: Xu D0D0π 0 (X(3875)) ; Xd J/ψπ + π (X(3872)) 31

32 Charged charmonium-like states (Z±) Z±(4430) Z±(4050) & Z±(4250) 32

33 Observation of Z+(4430) state New state observed in B K (2S) decays PRL PRL100, 100,142001(2008) (2008) BB BB B K ± (K=K±, KS0; ℓ+ℓ- or J/ψ( ℓ+ℓ-)π+π- with mπ+π->0.44gev) Clear signals in both ΔE and Mbc seen mk kinemat. constrained to mb σ~2.5mev for M(πψ') M( ± ) fit: S-wave Breit-Wigner and PS-like function K*(1430) M2( ) (GeV2/c4) K*(890) 2.5 σ window M2(K ) (GeV2/c4) 33

34 Observation of Z+(4430) state New state observed in B K (2S) decays PRL PRL100, 100,142001(2008) (2008) BB BB B K ± (K=K±, KS0; ℓ+ℓ- or J/ψ( ℓ+ℓ-)π+π- with mπ+π->0.44gev) Clear signals in both ΔE and Mbc seen mk kinemat. constrained to mb σ~2.5mev for M(πψ') M( ± ) fit: S-wave Breit-Wigner and PS-like function K*(1430) veto M2( ) (GeV2/c4) K*(890) veto 2.5 σ window M = (4433 ± 4 ± 2) MeV/c2 Γ = ( ) MeV M2(K ) (GeV2/c4) Z(4430)+ 121±30 events (6.5 σ) robust signal (subsamples;veto) too narrow state to be explained by interference of known S-, P-, D-wave K resonances M( ) (GeV/c2) 34

35 Observation of Z+(4430) state PRL PRL100, 100,142001(2008) (2008) BB BB Z(4430)+ ψ(2s)π+ : Charged state that decays like charmonium (= charged charmonium-like state) Br( B0 K- Z+(4430) ) Br( Z+(4430) + ' ) = ( 4.1 ± 1.0 ± 1.4 ) x 10-5 Not enough statistics to determine JP (Some) possible interpretations: [cu][cd] tetraquark with JP=1+ ( Radial excitation of X(3872) family? ) - Neutral partner in decays: ψ π0/η, ηc ρ0/ω? - Charged 1S state in decays: ψπ±, ηcρ±? { Maiani et al., arxiv:hep-ph/ } D*D1(2420) threshold effect { Rosner, PRD 76, (2007) } D*D1(2420) molecule with JP=0-, 1Decay to D*D*π expected. { Meng et al., hep-ph/ }... and more... First serious tetraquark candidate M( ) (GeV/c2) Confirmation needed 35

36 Z+(4430) update: Dalitz analysis The default Dalitz fit model used: All known K* resonances with J=0,1,2 below 1780 MeV/c2 B K (2S) Fit without a Z resonance: Dalitz plot slices: B C D E A B C D Pr e lim in ar y A Presented QWG'08 '08 22ndnd --55thth December December E CL=0.1% K*(890) band K*(1430) band Include a Z reson. 36

37 Z+(4430) update: Dalitz analysis The default Dalitz fit model used: All known K* resonances with J=0,1,2 below 1780 MeV/c2 B K (2S) Fit with a Z resonance: Dalitz plot slices: B C D E A B C D Pr e lim in ar y A Presented QWG'08 '08 22ndnd --55thth December December σ significance E CL of the fit with Z±(4430) is 36% K*(890) band K*(1430) band 37

38 Z+(4430) update: Dalitz analysis lim Pr e - Fit with Z±(4430) - without Z±(4430) - background To To be besubmitted submittedto to the theprd(rc) PRD(RC) (with (with BB) BB) in ar y Sum of A, C, E slices (= K* s veto) : Original result confirmed (w K* veto) & Z±(4430) parameters updated (w/o veto): M = ( ) MeV/c2 Γ = ( ) MeV Width larger than original (45MeV), but uncertainties are also large Systematics studies/crosscheks: Z±(4430) signif. in different fit models always > 5.4σ Not a B 'K3* (1780) reflection Br( B0 K- Z+(4430) ) Br( Z+(4430) + ' ) = ( ) x

39 More Z+ states: Z+(4050) & Z+(4250) Another B K- + (cc) mode : PRD PRD78, 78, (2008) (2008) BB BB New states observed in B0 K- + c1 decays B0 K- + c1 ( c1 J/ψγ ; J/ψ l+l- ) Clear signals in ΔE, Mbc, M(J/ψγ) Dalitz plot analysis: K0*(1430) K*(892) K2*(1430) K*(1680) K*(1780) ΔE M(J/ψγ) Fit model: Include all K* resonances below 1900 MeV/c2 Integrated χ, J/ψ angular distributions c1??? (no sensitivity) Correction for Lorentz non-invariance of helicity Binned (400x400) maximum likelihood fit Fit results depicted in M 2 for M 2 bands

40 More Z+ states: Z+(4050) & Z+(4250) Data favour fit with 2 resonant structures: one Z (10.7σ) ; Z1 and Z2 (13.2σ ; 5.7σ wrt. one Z) Spin of Z1,2 is not determined: J=0 and J=1 hypotheses give comparable results PRD PRD78, 78, (2008) (2008) BB BB M(χc1π+) for 1<M2(K-π+)<1.75GeV Z1,2 parameters: large syst. errors due to model uncertainties null hypothesis (CL=3x10-10) Z1+Z2 model (CL = 42%) Z1 contribution Z2 contribution BF product comparable to Z+(4430), X(3872) Z+(4050), Z+(4250) join Z+(4430) as charged charmonium-like exotics: Tetraquark candidates Experimental confirmation is still needed for all of them 40

41 Double cc production:j/ψ & C=+1 state Inclusive production: charmonia X factory ee+ Reconstruct J/Ψ ℓ + ℓ - Belle : 357 fb-1 PRL 98, (2007) X(3940) D(*)D? reconstruct J/Ψ + only one D (to increase reconstruction efficiency) constrain M recoil (J/Ψ D)=M(D(*)) (to improve resolution: σ(m recoil(j/ψ))~10 MeV/c2) (mass & vertex constrained fit) J/ψ Recoil mass (mass of X): M recoil = E cms E * 2 J /ψ p Mrecoi l ( J/ψ D) =M( D) 2 * J /ψ 266±63 events M~3936 MeV/c2 Mrecoi l ( J/ψ D) =M( D*) (24.5±6.9) evts 5σ σ(mrecoil) ~ 30 MeV/c2 New state M=(3943±6±6) MeV/c2 Γ < 52 C.L. 41

42 Double cc production: update Used the established method to look for the PRL PRL100, 100,202001(2008) (2008) fb fb-1 D(*)D(*) resonances in e+e- J/ψ D(*)D(*) with larger statistics... Reconstruct J/Ψ+D(*): Accompanying D(*) peaks seen in Mrecoil(J/Ψ D(*)) distr. Processes tagged in this way: J/ΨDD, J/ΨDD*, J/ΨD*D*, J/ΨD*D,J/ΨD*D* (all > 5σ) Mrec(J/ψD) D D* D*π Mrec(J/ψD*) D D* 693fb-1 Constrain Mrecoil(J/Ψ D(*))=Mnominal(D(*)) and look at Mrecoil(J/Ψ) = Mrecoil(D(*)D(*)) distributions... 42

43 Double cc prod.: X(3940) and X(4160) D D* D*π Mrec(J/ψD) PRL PRL100, 100,202001(2008) (2008) fb fb-1 D D* Mrec(J/ψD*) e+e- J/ψ D D* e+e- J/ψ D* D* X(3940) 6.0σ M(D*D) M=( ± 6) MeV Γ=( ± 12) MeV X(4160) 5.5σ New! 4.5 M(D*D*) M=( ± 15) MeV/c2 C =+1: X Γ=( ± 21) MeV/c2 X(4160) ψ(4160) Possible assignments: ηc(3s), (3S) ηc(4s), (4S) c0(3p) (but masses MeV too high) Needed to be done: angular analysis; search in DD*, D*D* 43

44 e+e- J/ψcc cross ~10.6 GeV Model-independent measurements of e+e- J/ψcc cross section - Simultaneous fit for all double charmonium final states PRD 79, (2009) PRD 79, (2009) fb fb-1 (below open-charm threshold) ηc χc0 ηc' J/ψ Mrecoil(J/ψ) ηc' ηc χ c0 ψ' Mrecoil(χc1) -Pairs of J/ψ and ground state charm hadrons: e+e- J/ψHcX (Hc=D0, D+, Ds+, Λc+) Hc=D0 J/ψ 10.1σ J/ψ ψ' Mrecoil(χc2) J/ψ Hc=Ds+ 3.2σ Hc sideband Hc sideband Mrecoil(ψ') J/ψ Hc=D+ + H = Λ c c J/ψ 7.8σ Hc sideband 2.2σ Hc sideband 44

45 e+e- J/ψcc cross ~10.6 GeV Model-independent measurements of e+e- J/ψcc cross section e+e- J/ψ X PRD PRD79, 79, (2009) (2009) fb fb-1 e+e- J/ψHcX e+e- J/ψ Xcc e+e- J/ψ cc e+e- J/ψ Xnon-cc Conclusions (new constraints for theoretical models): e+e- J/ψcc is the dominant mechanism for J/ψ production in e+e- annihilations e+e- J/ψcc is dominated by cc fragmentation into open charm ( only (16±3)% from double charmonium ) + + σ(e e J/ψ cc) / σ(e e J/ψ X ) ~ O(1) non-cc 45

46 Many Y states with Initial State Radiation 46

47 Study of 1- - states with ISR Initial state radiation (ISR) gives access to JPC = 1- - states ISR e - Information on 1- - charmonia above the open-charm threshold * Two main characteristics of ISR physics at B-factories: - Continuous ISR spectrum gives access to the wide s range Xcc1 -- e+ - High luminosity compensates for the emission of hard photons Sensitivity comparable to direct energy scan (e.g. CLEO-c, BES III) PRL 95,142001(2005) Y(4260) Y(4260) J/ψπ+π- observed via ISR by BaBar (confirmed first by CLEO) ψ(2s) 8σ 233 fb-1 BaBar's approach used also by Belle to search for these 1-- states 47

48 Study of 1- - states in e+e- ISRJ/ψπ+πUsing BaBar's approach Study of e+e- ISR J/ψπ+π- also by Belle Reconstruction: π+π- & J/ψ( e+e-,μ+μ-) (no extra tracks allowed; ISR not detected ) Missing(recoil) mass identifies ISR: M rec= E cms E * 2 + J/ ψ p * 2 J / ψ + - Y(4260) New? PRL PRL99, 99, (2007) (2007) Y(4008) 548 fb fb-1 Fit to M(J/ψπ+π-) with two coherent BW curves Y(4260) is confirmed also by Belle New Y(4008) resonance? { Might be: re-scattering from DD*; coupled-channel effect?} 48

49 Study of 1- - states in e+e- ISRJ/ψπ+πUsing BaBar's approach Study of e+e- ISR J/ψπ+π- also by Belle Reconstruction: π+π- & J/ψ( e+e-,μ+μ-) (no extra tracks allowed; ISR not detected ) Missing(recoil) mass identifies ISR: M rec= E cms E * 2 + J/ ψ p * 2 J / ψ + - Y(4260) New? PRL PRL99, 99, (2007) (2007) Y(4008) 548 fb fb-1 Fit to M(J/ψπ+π-) with two coherent BW curves Y(4260) is confirmed also by Belle New Y(4008) resonance? Not seen by BaBar... Update preliminary Y(4260) Y(4008)? (344±39) events 454 fb-1 49

50 Study of 1- - states in e+e- ISRψ'π+πSimilar approach also for: PRL PRL99, 99, (2007) (2007) fb-1 fb-1 Study of e+e- ISR ψ(2s)π+π- Reconstruction: π+π- & ψ(2s)( π+π-j/ψ( e+e-,μ+μ-)) (no extra tracks allowed; ISR not detected ) Missing(recoil) mass identifies ISR: M rec= E cms E ψ 2S pψ 2S * * Fit to M(ψ(2S)π+π-) with two coherent BW curves Belle's Y(4360) resonance: close to BaBar's Y(4325), but narrower New Y(4660) resonance by Belle? New? New? Y(4360) Y(4660) 50

51 Study of 1- - states in e+e- ISRψ'π+πSimilar approach also for: PRL PRL99, 99, (2007) (2007) fb-1 fb-1 Study of e+e- ISR ψ(2s)π+π- Reconstruction: π+π- & ψ(2s)( π+π-j/ψ( e+e-,μ+μ-)) (no extra tracks allowed; ISR not detected ) Missing(recoil) mass identifies ISR: M rec= E cms E ψ 2S pψ 2S * New? New? Y(4360) Y(4660) * Fit to M(ψ(2S)π+π-) with two coherent BW curves Belle's Y(4360) resonance: close to BaBar's Y(4325), but narrower New Y(4660) resonance by Belle? (Seen also by BaBar?) PRL 98, (2007) Y(4325) ψ (2S)π π Y(4660)? 298 fb-1 51

52 Study of e+e- ISR Λc+ Λc- : X(4630)? PRL101, 101, (2008) (2008) Reconstruction: Λc+( pks0, pk-π+, Λπ+ )& ISR detected; p (from Λc-) PRL 695 fb fb e e Λc Λc γisr X(4630)? w 8.2σ Ne Interpretations for the enhancement : Dibaryonic peak near the threshold seen e.g. in B pλcπ... PRL 97, (2006) 6.2σ Could be also: X(4630) = Y(4660) (compatible mass, width)? B Λc+p π... but there is no peaking structure in a similar decay: PRD PRL 76, 99,142002(2007) (2007) ee ΛΛ via ISR Can not exclude 53S1 charmonium : in some models M (53S1) ~4670MeV 52

53 Exclusive D(*)D(*) cross sect. with ISR PRD 77, (2008) 673 fb-1 Results: Difficult interpretation in terms of resonances (there are many maxima/minima, model dependent coupled-channels and threshold effects ) D0D- π+ PRL98, (2007) 548 fb-1 D*+D*Y(4660) PRL 100, (2008) 673 fb-1 Y(4360) ψ (4160) Method is well established D+D*- ψ (4415)? Y(4260) DD: fully reconstructed; ISR used if detected Recoil mass is again used to identify ISR events DD ψ(4040) e+e- DD, DD*, D*D* cross sections measured with ISR DD*, D*D*: using partial reconstruction; ISR detected Y(4008) PRL 101, (2008) 695 fb-1 Λc+Λc 53

54 1- - Y states: What are they? Difficult interpretation Charmonium options: Y states above DD threshold but don t match well the peaks in D(*)D(*) cross-sections Large widths for ψππ transition: not likely for conventional cc No cc assignments available in this mass region (there are too many 1-- states) + - J/ψ Y(4260) PRL PRL99, 99, (2007) (2007) Y(4008) Y(4660) Y(4360) + - ψ PRL PRL99, 99, (2007) (2007) Other options: Charm-meson threshold effects DD1 or D*D0 molecules cqcq tetraquarks ccg hybrids predicted@4.25gev DD1 mode should dominate Coupled-channel effects PRD PRD77, 77, (2008) (2008) Κ + Κ J/ψ 54

55 Summary and conclusions 55

56 Summary and conclusions DsJ states : Ds0*(2317)± and Ds1(2460)± better understood, but mass shift not clear yet... New DsJ state observed in B D0 D0 K+: DsJ(2700)+ D0 K+ Ds1(2460)± - Ds1(2536)± mixing? (HQET not so good ) Also DsJ(2860)+ from BaBar New results (from complete Dalitz) are eagerly awaited... 56

57 Summary and conclusions Charmonium(-like) states : Following the exciting X(3872) discovery New exotic state observed by Belle in B ψ(2s)π±k decays: Z(4430)+ (charged charmonium-like state)... also Z1+ and Z2+ in B0 K- + c1 decays New charmonium[-like] spectroscopy established at 4-5GeV? Good candidates for molecular states; multiquarks; hybrids;... X(3872); Z(4430)+, Z1+ and Z2+; Y's;... Q: Same type of XYZ spectroscopy in b(s)-quark sector? As the data taking/processing is still going on (until March 2010), more interesting results/new states could come from Belle stay tuned for more news! 57

58 Supplementary material

59 Asymmetric-energy e+e colliders 2 KEKB E CMS ~m 4S c =10.58 GeV 2.11x10 cm s-1(wr!) 8.5 GeV e (HER) 3.5 GeV e+ (LER) Ratei = Lumi. x σi 9.0 GeV e (HER) 3.1 GeV e+ (LER) PEP-II x10 cm-2s-1

60 Mass (GeV/c2) DsJ first results from cc (reminder) 3.4 Belle : 87 fb-1 PRL 92, (2004) 3.0 DsJ*(2317)+ Ds+ 0 DsJ(2460)+ Ds+ 2.6 Ds*+ 2.2 Ds+? 1.8 well-known DS mesons 0 D D + sj s e c s e- c s K+K- M inv = Σ i E i 2 - Σ i p i 2

61 DsJ first results from B decays (rem.) Belle : 124M BB PRL 91, (2003) B D DsJ DsJ (2317) * update Belle : 274M BB BELLE-CONF0461 (2004) Ds + Ds + 0 Angular distribution is D spin-dependent: DsJ B, 0 J=1 DsJ(2460) + Ds*+ 0 DsJ(2460)+ Ds+ J=1 J=0 DsJ*(2317)+ Ds+ 0 J=2 DsJ(2460)+ Ds+ Distributions are consistent with: JP=0+ (DsJ*(2317)+) and 1+(DsJ(2460)+) e.g. Br( B0 D- DsJ*(2317)+ ) = ( 10.1 ± 1.5 ± 3.0 ) x 10-4

62 DsJ states updates from B decays B D DsJ*(2317)+, DsJ*(2317)+ Ds+π0 Belle: 274M BB BELLE-CONF0461 (2004) DsJ*(2317) decay mode natural spin-parity DsJ*(2317) decay angular distribution spin 0 Dotted line: J=1 χ2/d.o.f = 38/8 π0 Solid line: J=0 χ2/d.o.f = 3/8 Natural spin-parity JP = 0+

63 DsJ states updates from B decays B D DsJ(2460)+ ; (b)dsj(2460)+ Ds+ ; (c)dsj(2460)+ Ds *(2112) +π0,ds*+ Ds+ Belle: 274M BB BELLE-CONF0461 (2004) Ds mode: absent, if J=0 Ds*π0 mode Dashed line: J=2 χ 2/d.o.f = 89/8 Solid line: J=1 χ2/d.o.f = 4/8 Solid line: J=1 S-wave JP = 1+ cos(θ D *π 0) s

64 DsJ more results from B decays(rem.) Belle : 152M BB PRL 94, (2005) First time observed: B0 DsJ*- K+ M(Ds 0)-M(Ds) 6.7 signif. E (GeV) 0.2 Br(B0 DsJ*(2317)-K+) Br(DsJ*(2317)- Ds- 0) Br(B D K ) 0 s + Br(B0 D-DsJ*(2317)+) Br(DsJ*(2317)+ Ds+ 0) Br(B0 D-Ds+) (GeV) = 1.8 ± 0.6 (same order of magnitude) = 0.13 ± 0.05 Initial and final q-content are completely different PQCD fact. W exchange tree with FSI Tetraquark content?

65 DsJ states updates from B decays B0 DsJ*(2317)+K- ; B0 DsJ(2460)+K- Belle : 386M BB hep-ex/ (Update with 386M BB) Two states are not from the same-spin doublet

66 Z(3930): conventional cc ( 'c2 ) Belle : 395 fb-1 PRL 96, (2006) e+ e+ * * Z D D ee un-tagged events (e+,e- undetected) D0 K- π+, K- π+ π0, K- π+ π+ πd+ K- π+ π+ pt(dd) < 0.05 GeV/c 64 ± 18 events M = (3929±5±2) MeV/c2 Γ = (29±10±2) MeV 5. 3σ D si de band M( DD) [ GeV/ c ] 2 acceptance corrected θ*: D, beam axis in γγ frame J=2 expectation 2/nof=1.9/9 J=0 expectation 2/nof=23.4/9 D si de band Γ γγ Z 3930 Br Z 3930 D D = 0.18±0.05 stat. ±0.03 syst. kev Z χ c2 23P2 cc S.Godfrey,N.Isgur,PRD32,189 (1985) C.R.Münz,Nucl.Phys.A609,364 (1996)

67 More info: Z+(4430) Dalitz analysis Different fit models and the significance of Z(4430)+: Significance of Z(4430)+ in different fit models is always larger than 5.4σ

68 Z1+ & Z2+ in B0 K- + c1 decays: fit Fit results: M2(χc1π+) projections in 4 M2(K-π+ ) bands Low M2(K-π+ ) Null hypothesis: all known K* s; poor fit : C.L. 3*10-10 Add Z χc1π+: signif. 10.7σ ( (-2lnL/L0) ), C.L. = 0.5% MZ=( ) MeV/c2 ΓZ=( ) MeV Two Z χc1π+: signif. wrt 1 Z: 5.7σ, C.L. = 42% Mid_L M2(K-π+ ) data background fit function... fit function without Z Mid_H M2(K-π+ ) High M2(K-π+ )

69 Z1+ & Z2+ : fit fractions There is small net interference effect

70 e+e- ISRψ'π+π- : BaBar & Belle combined fit