Bottomonia & charmonia at B-factories

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1 Bottomonia & charmonia at B-factories Pavel Krokovny Budker Institute of Nuclear Physics, Novosibirsk, Russia Introduction Bottomonium states Z b (10610) and Z b (10650) Charmonium states Study of X, Y, Z states Evidence for ψ 2 Summary Moriond QCD 2013

2 Introduction ϒ(4S): 433 fb-1 ϒ(3S): 30 fb -1 ϒ(2S): 14 fb -1 ϒ(5S): 121 fb -1 ϒ(4S): 703 fb -1 Heavy Quarkonia are ideal tool for testing QCD 2

3 Discovery of Z b In analysis of ϒ(5S) h b (mp)π + π and ϒ(5S) ϒ(nS)π + π h b (1P) yield / 10MeV M(h b π), GeV/c 2 h b (1P) yield / 10MeV M(h b π), GeV/c 2 fit M miss (π + π ) in M(h b π) bins PRL 108, (2012) 3

Summary of Z b parameters Average over 5 channels M 1 = 10607.2±2.0 MeV Γ 1 = 18.4±2.

4 Summary of Z b parameters Average over 5 channels M 1 = ±2.0 MeV Γ 1 = 18.4±2.4 MeV M(BB*)= ± 0.4 MeV M 2 = ±1.5 MeV Γ 2 = 11.5 ± 2.2 MeV M(B*B*)= ± 0.8 MeV 4

5 Z b angular analysis Zb (10610) Belle PRELIMINARY Zb (10650) Angle between prompt pion and beam axis ϒ μ + μ helicity angle Angle between planes formed by (π + π ) and (ϒ, beam axes) Confirms J P =1 + hypothesis 6D amplitude analysis of decays ϒ(5S) ϒ(nS)π + π 5

6 ϒ(5S) B * B (*) π: Selection Masses of Z b (10610) and Z b (10650) are close to BB* and B*B* threshold. Search for Y(5S) Z b π decay with Z b B ( * ) B*; reconstruct only one B and prompt pion Data 2 body ϒ(5S) decays Data (B signal) B*B* BB* BB Data (B side bands) Effective B fraction: Br[B f] = 1.4 x 10 3 Charged B: D 0 [Kπ,Kπππ]π, J/ψ[μμ] K Neutral B: D + [Kππ]π, J/ψ[μμ] K* 0, D* + [Kπ,Kππ 0,Kπππ]π 3 body ϒ(5S) >B(*)B(*)π decays & ISR to ϒ(4S): P(B)<0.9 GeV/c Belle PRELIMINARY 6

7 ϒ(5S) B * B (*) π: Fit MC: B*Bπ Recoil mass to Bπ combinations Belle PRELIMINARY BB*π B*B*π MC: B*B*π (shifted by 45MeV) Fit yields: N(BBπ) = 0.3 ± 14 N(BB*π) = 184 ± 19 (9.3σ) Red histogram: right charge combination Bπ; Hatched histogram: wrong charge combination; The curve show the fit to the data. arxiv: N(B*B*π) = 82 ± 11 (5.7σ) 7

8 ϒ(5S) B * B (*) π: Search for Z b BB*π Z b (10610) B*B*π Z b (10650) 8σ Z b (10610) + Z b (10650) PhSp Z b (10610)+ PhSp Z b (10610) + Z b (10650) + PhSp Points represent the data. Curves show the fit with various models. Hatched histogram is the background contribution. Belle PRELIMINARY 6.8σ Z b (10650) alone PhSp Z b (10650)+ PhSp arxiv: B*B*π candidates are well described by Z b (10650) only contribution. BB*π can be described by two models: Z b (10610) + Z b (10650); Z b (10610) + non-resonant amplitude. 8

9 Z b branching fractions ϒ(5S) branching fractions: BBπ < 0.60% (90%CL) BB*π = 4.25 ± 0.44 ± 0.69% B*B*π = 2.12 ± 0.29 ± 0.36% Assuming Z b decaying to ϒ(nS)π, h b (mp)π and B(*)B*only: arxiv: Belle PRELIMINARY B(*)B* is the dominant mode of Z b decays 9

10 ϒ(5S) ϒ(nS)π 0 π 0 arxiv: ϒ(1,2,3S) μ + μ, e + e, ϒ(2S) ϒ(1S)π + π μ + μ π 0 π 0 e + e π 0 π 0 μ + μ π + π π 0 π 0 ϒ(1S) ϒ(2S) ϒ(3S) ϒ(1S) ϒ(2S) ϒ(2S) reflection BF[ϒ(5S) ϒ(1S)π 0 π 0 ] = (2.25±0.11±0.20) 10 3 BF[ϒ(5S) ϒ(2S)π 0 π 0 ] = (3.79±0.24±0.49) 10 3 Belle PRELIMINARY Consistent with ½ of Y(nS)π + π 10

11 ϒ(2S)π 0 π 0 Dalitz analysis arxiv: with Z b 0 w/o Z b 0 Belle PRELIMINARY Z b0 resonant structure is observed in ϒ(2S)π 0 π 0 Statistical significance of Z b0 (10610) signal is 5.3σ (4.9σ with systematics) Z b0 (10650) signal is not significant (~2σ), not contradicting with its existence Z b0 (10610) mass from the fit M=10609 ± 8 ± 6 MeV/c 2 M(Z b+ )=10607±2 MeV/c 2 11

12 ϒ(1S)π 0 π 0 Dalitz analysis Dalitz analysis with Z b 0 w/o Z b 0 Belle PRELIMINARY Signals of both Z b0 are not significant. Data is not contradicting with their existence. arxiv:

13 Update of X(3872) J/ψπ + π Observed 10 years ago by Belle in B J/ψπ + π K PRL 91, (2003) Update using BB PRD 84, (2011) M(3872)= ± 0.27 ± 0.19 MeV/c 2 ; Γ(3872)<1.2 90% CL Mass difference of X(3872) from B + and B 0 : ΔM = ± 0.97 ± 0.19 MeV/c 2 13

14 Search for charged X Charged partner can exist if X(3872) is exotic. Search for X(3872) + in J/ψρ + B 0 K - ρ + J/ψ B + K 0 ρ + J/ψ B(B 0 X + K - )xb(x + J/ψρ + )< B(B + X + K 0 )xb(x + J/ψρ + )< PRD 84, (2011) 14

15 Search for C-odd partner of X(3872) ψ no X(3872)? Μ(χ c1 γ) 15

094019 (2004) Β ψ K, ψ χ c1 γ Belle PRELIMINARY Β ψ 2 K, ψ 2 χ c1 γ First ψ 2

16 Evidence for ψ 2 χ c1 γ ψ 2 χ c1 γ was predicted, Γ(ψ 2 χ c1 γ)=260 KeV Godfrey & Isgur, PRD 21, 189 (1985); Eichten, Lane & Quigg, PRL (2002) & PRD 69, (2004) Β ψ K, ψ χ c1 γ Belle PRELIMINARY Β ψ 2 K, ψ 2 χ c1 γ First ψ 2 evidence ψ 2 significance is 4.2σ including systematics Γ(ψ 2 ) = 4 ± 6 MeV from the fit 16

17 e + e J/ψπ + π and ψ(2s)π + π by ISR ψπ + π ψ(2s)π + π PRD (2012) Y(4260): M = 4245 ± 5 ± 4 MeV/c 2 Γ = 114 ± 15 ± 7 MeV arxiv: Y(4360): M = 4340 ± 16 ± 9 MeV/c 2 Γ = 94 ± 32 ± 13 MeV Y(4660): M = 4669 ± 21 ± 3 MeV/c 2 Γ = 104 ± 48 ± 10 MeV Consistent with previous Belle results 17

18 e + e - J/ψη by ISR First time ψ(4040) and ψ(4160) have been observed in final states not involving charm meson pair. No signal from Y(4260/4360/4660). arxiv:

19 X(3915) J/ψω in two-photons collisions 7.6σ significance M = ± 2.2 ± 1.6 MeV/c 2 Γ = 13 ± 6 ± 3 MeV J P =0 + Consistent with older studies by BaBar & Belle PRD (2012) 19

20 Summary New results on bottomonium states come from B factories: Observation of Z b+ (10610) and Z b+ (10650) decays to BB * and B * B * main decay mode, supporting molecular hypothesis 6D amplitude analysis of ϒ(5S) ϒ(nS)π + π - confirmed J P =1 + for both Z b Evidence for neutral partner Z b (10610) in analysis of ϒ(5S) ϒ(2S)π 0 π 0 consistent with expectation from isospin and on charmonium states: No charged or C-odd partners of X(3872) have been found A first evidence of ψ 2 is obtained in B Kχ c1 γ decay Y(4260/4360/4660) are seen in ψ(1,2s)π + π, however no evidence in J/ψη 20

21 Back up 21

22 Comparison with ϒ(nS)π + π - Fit to the Y1Sπ + π - data Fit to the Y2Sπ + π - data Background subtracted YnSπ 0 π 0 data 22

Heavy quark structure in Z b Bondar, Garmash, Milstein, Mizuk, Voloshin Phys.Rev.D 84 054010 Wave func.

23 Heavy quark structure in Z b Bondar, Garmash, Milstein, Mizuk, Voloshin Phys.Rev.D Wave func. at large distance B(*)B* Z Z ' b b = = Explains bb bb 1 1 Qq Qq bb Why h b ππ is unsuppressed relative to ϒππ bb 0 0 Qq Qq Relative phase ~0 for ϒ and ~180 0 for h b Production rates of Z b (10610) and Z b (10650) are similar Widths Predicts Existence of other similar states Other Possible Explanations Coupled channel resonances (I.V.Danilkin et al, arxiv: ) Cusp (D.Bugg Europhys.Lett.96 (2011),arXiv: ) Tetraquark (M.Karliner, H.Lipkin, arxiv: ) 23

24 Observation of ϒ(5S) h b (np)π + π PRL 108, (2012) spin-flip no spin-flip = for h b (1P) for h b (2P) Process with spin flip of heavy quark is not suppressed: mechanism of ϒ(5S) h b (np) π + π - decay violates Heavy Quark Spin Symmetry 24

25 Search for decay h b η b γ Decay chain + ϒ(5S) Z b π - h b (np) π + η b (ms) γ reconstruct Use missing mass to identify signals MC simulation M(η b ) true π + π - fake γ fake π + π - true γ true π + π - true γ ΔM miss (π + π - γ) M miss (π + π - γ) M miss (π + π - ) + M[h b ] Approach: fit M miss (π + π - ) spectra in ΔM miss (π + π - γ) bins M(h b ) h b (1P) yield vs. ΔM miss (π + π - γ) search for η b (1S) signal 25

Observation of h b η b (1S) γ h b (1P) η b (1S) 15σ M [η b (1S)] = 9402.4 ± 1.5 ± 1.8 MeV/c 2 + 4.0+ 4.5 Γ[η b (1S)] = MeV 10.8 3.7 2.

26 Observation of h b η b (1S) γ h b (1P) η b (1S) 15σ M [η b (1S)] = ± 1.5 ± 1.8 MeV/c Γ[η b (1S)] = MeV potential models : Γ = 5 20 MeV Β[h b (1P) η b (1S)γ] = (49.2 ± ) % -3.3 Godfrey & Rosner : BF = 41% h b (2P) η b (1S) ΔM HF [η b (1S)] = 57.9 ± 2.3 MeV/c 2 9σ PRL 109, (2012) 26

Evidence of h b η b (2S) γ h b (2P) η b (2S) 4.2σ + 2.8 M [η b (2S)] = 9999.

9 Β[h b (2P) η b (2S)γ] = (47.5 ± 10.5 +6.8 ) % -7.7 4.0 ΔM HF [η b (2S)] =.

27 Evidence of h b η b (2S) γ h b (2P) η b (2S) 4.2σ M [η b (2S)] = ± 3.5 MeV/c Γ[η b (2S)] = MeV Β[h b (2P) η b (2S)γ] = (47.5 ± ) % ΔM HF [η b (2S)] =.3 MeV/c ΔM HF = 23.5 ±4.7 MeV Lattice Meinel PRD82,114502(2010) PRL 109, (2012) 27

28 ϒ(5S) ϒ(1D)π + π 5 3 S 1 π + π First and only one L=2 state found in radiative decay chain CLEO(2004): ϒ(3S) χ b (2P)γ ϒ(1D)γγ χ b (1P)γγγ ϒ(1S)γγγγ Belle measured a new production chain ϒ(5S) ϒ(1D)π + π χ b (1P)γπ + π ϒ(1S)γγπ + π CLEO M = ±0.6±1.6 MeV B[ϒ(3S) ϒ(1D)γγ ϒ(1S)γγγγ] = (2.5±0.5±0.5) 10 5 Belle preliminary B[ϒ(5S) ϒ(1D)π + π ϒ(1S)γγπ + π ] = (2.0±0.4±0.3) 10 4 Y(2S) Y(1D) Y(2S)[Yπ + π ]η[γγ] reflection statistical significance 9s

29 ϒ(2S) ϒ(1S)η η γγ η π + π π 0 Phys.Rev.D Β[ϒ(2S) ϒ(1S)η]=(3.41 ± 0.37 ± 0.35) 10-4 Β[ϒ(2S) ϒ(1S)π 0 ]< Β[ϒ(2S) ϒ(1S)η]=(2.39 ± 0.31 ± 0.14) 10 PRD 87, (R) (2013) -4 Β[ϒ(3S) ϒ(1S)η]<

30 Observation of ϒ(5S) ϒ(1,2S)η MM(π + π π 0 ) Three modes: ϒ(1,2S)[μ + μ ] η[π + π π 0 ] ϒ(2S)[ϒ(1S)π + π ] η[γγ] ϒ(1S)[μ + μ ] η [ηπ + π ] M(γγ) B[ϒ(5S) ϒ(1S)η] = (7.3±1.6±0.8) 10-4 preliminary B[ϒ(5S) ϒ(2S)η] = (38 ± 4 ± 5) 10-4 B[ϒ(5S) ϒ(1S)η ] <

Study of Transitions and Decays of Bottomonia at Belle

1 Study of Transitions and Decays of Bottomonia at Belle Saurabh Sandilya University of Cincinnati (On behalf of the Belle Collaboration) Outline Introduction (Bottomonia, KEKB & Belle detector) Transitions