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1 Recent Results on ϒ(5S) from Belle Alexey Garmash, BINP Novosibirsk on behalf of the Belle Collaboration HEP-MAD 2011, Antananarivo, August

2 KEKB & Belle KEKB an asymmetric energy 3.5GeV e+ vs. 8.0GeV e collider With continuous injection mode Delivering luminosity of ~1fb 1/day 1/day 2

BINP Chiba U. U. of Cincinnati Ewha Womans U. Fu-Jen Catholic U. U. of Giessen Gyeongsang Nat l U. Hanyang U. U. of Hawaii Hiroshima Tech.

of Nucl. Phys. Kyoto U. Kyungpook Nat l U. EPF Lausanne Jozef Stefan Inst. / U. of Ljubljana / U. of Maribor U.

Nihon Dental College Niigata U. Nova Gorica Osaka U. Osaka City U. Panjab U. Peking U. Princeton U. Riken Saga U.

of Tech. Tokyo Metropolitan U. Tokyo U. of Agri. and Tech. INFN Torino Toyama Nat l College VPI Yonsei U.

3 BINP Chiba U. U. of Cincinnati Ewha Womans U. Fu-Jen Catholic U. U. of Giessen Gyeongsang Nat l U. Hanyang U. U. of Hawaii Hiroshima Tech. IHEP, Beijing IHEP, Moscow Belle International Collaboration IHEP, Vienna ITEP Kanagawa U. KEK Korea U. Krakow Inst. of Nucl. Phys. Kyoto U. Kyungpook Nat l U. EPF Lausanne Jozef Stefan Inst. / U. of Ljubljana / U. of Maribor U. of Melbourne Nagoya U. Nara Women s U. National Central U. National Taiwan U. National United U. Nihon Dental College Niigata U. Nova Gorica Osaka U. Osaka City U. Panjab U. Peking U. Princeton U. Riken Saga U. USTC Seoul National U. Shinshu U. Sungkyunkwan U. U. of Sydney Tata Institute Toho U. Tohoku U. Tohuku Gakuin U. U. of Tokyo Tokyo Inst. of Tech. Tokyo Metropolitan U. Tokyo U. of Agri. and Tech. INFN Torino Toyama Nat l College VPI Yonsei U. 13 countries, ti 57 institutes t 13 countries, 57 institutes, ~400 collaborators 8/24/ countries, 57 institutes, ~400 collaborators 3

4 Bottomonium Family 4

02), 14 fb -1 ϒ(3S): (10.36), 30 fb -1 ϒ(4S): (10.

5 e+e- Hadronic Cross-section ϒ(1S) ϒ(2S) ϒ(3S) 2M(B) ϒ(4S) Res: (E CM (GeV)), lum ϒ(1S): ( 9.46), 6 fb -1 ϒ(2S): (10.02), 25 fb -1 ϒ(3S): (10.36), 3 fb -1 ϒ(4S): (10.58), 710 fb -1 ϒ(5S): (10.87), 121 fb -1 Off resonance: 87 fb -1 ϒ(2S): (10.02), 14 fb -1 ϒ(3S): (10.36), 30 fb -1 ϒ(4S): (10.58), 433 fb -1 Off resonance: 54 fb -1 ϒ(4S) ( ) 2M(B s ) ϒ(5S) ϒ(6S) Belle took data at E = 10867± 1 MэВВ L = fb -1 e + e >ϒ(4S) >_ BB, where B is B + or B 0 e + e > bb (ϒ(5S)) > B ( * ) _ B ( * ), B _ ( * ) B ( * ) π, BBππ, _ B ( ( s( * ) B s( * ), ϒππ, ϒ X 5

6 Puzzles of ϒ(5S) Decays Anomalous production of ϒ(nS) π + π observed Dedicated energy scan shapes by Belle with 21.7 fb 1 of R b and σ(ϒππ) differs at 2σ level PRL100,112001(2008) Γ(MeV) ~10 2 (1) Rescattering ϒ(5S) BBππ ϒ(nS)ππ Simonov JETP Lett 87,147(2008); Meng et al. Phys.Rev.D78:034022,2008 (2) Exotic resonance Y b near ϒ(5S) analogue of Y(4260) resonance with anomalous Γ(J/ψ π + π ) Hou et al., Phys.Rev.D74:017504,2006 Ali et al. Phys.Rev.Lett.104:162001,2010 PRD82,091106R(2010) (3) Tetraquarks Karliner et al. arxiv: v2; Xiang Liu et al. Eur. Phys. J. C (2009) 61: 411; Yan Rui Liu et al. Eur.Phys.J.C56:63 73,2008; N. Brambillaet bll al, Eur.Phys.J. C71 (2011) 1534 Now Belle recorded 121fb 1 of data at ϒ(5S) 6

7 Input from Charm Sector Observation of e + e π + π h c by CLEO CHARM2010 Energy dependence of the cross section arxiv: σ(h c π + π ) is Y(4260) σ(h b π + π ) is Y b? 7

8 h States _ (bb) : S=0 L=1 J PC =1 +- Expected mass (CoG of χ bj ) Eid Evidence from BB BaBar: ϒ(3S) π 0 h b (1P) π 0 γη b (1S) M hb (Mχ b0 + 3 Mχ b1 + 5 Mχ b2 ) / 9 ΔM HF test of hyperfine interaction For h c ΔM HF = 0.12 ± 0.30 MeV/c 2, and even smaller deviation is expected for the h b (np). 3.0σ B(ϒ(3S) π 0 h b )xb(h b γη b )=( )x10 4 b b γη b arxiv:

9 h b Reconstruction Missing Mass to π + π - system M hb(np) = (P ϒ(5S) P π+π ) 2 MM(π + π ) Simple selection : π ± : good track quality, consistent PID information Suppression of continuum events with Fox Wolfram moment R 2 <0.3 Search for h b (np) peaks in MM(π + π ) spectrum 9

10 h b Reconstruction Missing Mass to π + π - system M hb(np) = (P ϒ(5S) P π+π ) 2 MM(π + π ) Simple selection : ϒ(1S) h b (1P) ϒ(2S) h b (2P) ϒ(3S) π ± : good track quality, consistent PID information Suppression of continuum events with Fox Wolfram moment R 2 <0.3 Search for h b (np) peaks in MM(π + π ) spectrum Data: fb 11 ~1M events in 1MeV bin! 10

Fitting The MM(π + π - ) Spectrum Three fit regions Fit to region 1 1 2 3 ϒ(1S) Residual BG: Chebyshev polynomial: max C.L.

11 Fitting The MM(π + π - ) Spectrum Three fit regions Fit to region ϒ(1S) Residual BG: Chebyshev polynomial: max C.L. of fit (order 6 or 7) Signal: shape is fixed from exclusive μ + μ π + π data Residual subtract polynomial from data points K S contribution: subtract bin by bin (for Region 3 only) 11

12 Fitting The MM(π + π - ) Spectrum Raw spectrum Background subtracted 3S 1S 2S 1 1S

13 Background Subtracted Results h b (1P) 5.5σ h b (2P) 11.2σ Significance with systematic uncertainties included For more details see arxiv:

14 Summary of h b Results Deviations from CoG of χ bj masses consistent with zero. Ratio of production rates Process with spin flip is not suppressed in ϒ(5S) However, no signal of h b is observed in at ϒ(4S) Mechanism of ϒ(5S) h b (np) π + π decay should be exotic! 14

15 Resonant Substructure in Y(5S) h b (1S)π + π - P(h b ) = P ϒ(5S) P(π + π ) M(h b π + ) = MM(π ) phase space MC combine

16 Resonant Substructure in Y(5S) h b (1S)π + π - measure ϒ(5S) h ππ yield P(h b ) = P ϒ(5S) P(π + π ) M(h b π + ( ) ) = MM(π ) b in bins of MM(π) phase space MC data combine PHSP Fit function P wave Breit Wigner functions Significances 2 vs.1 : 7.4σ (6.6σ w/ syst) 2 vs.0 : 18σ (16σ w/ syst) non-res. amplitude ~0 16

17 Resonant Substructure in Y(5S) h b (2S)π + π - phase space MC data combine PHSP M 1 = M 2 = Γ 1 = Γ 2 = h b (1P)π + π h b (2P)π + π MeV/c 2 MeV MeV/c 2 MeV MeV/c 2 MeV MeV/c 2 MeV a = ϕ = degree degree Significances 2 vs.1 : 2.7σ (1.9σ w/ syst) 2 vs.0 : 6.3σ (4.7σ w/ syst) 17

18 Exclusive Y(5S) Y( Y(nS)π + π - ϒ(5S) ϒ(nS) π+π ϒ(nS) μ+μ (n = 1,2,3) 123) ϒ(3S) ϒ(2S) ϒ(5S) decay band ϒ(1S) reflections & cascade decays 18

19 Y(nS) Signal Selection Projections onto MM(π + π - ) axis ϒ(1S) ϒ(2S) ϒ(3S) Plot these events as M(ϒπ) 2 vs. M(π + π ) 2 arxiv: v1 19

20 Y(5S) Y( Y(nS)π + π - Dalitz Plots Signal Signal Signal ϒ(1S) Photon conversions ϒ(3S) ϒ(2S) Sideband Sideband Sideband 20

21 Y(5S) Y( Y(nS)π + π - Decay Amplitude Flatte: m=950 MeV/c 2 ; g ππ =0.23; g KK =0.73 From the analysis of B Kππ by Belle D-wave Breit-Wigner MB M.B. Voloshin, Prog. Part. Nucl. Phys. 61:455, M.B. Voloshin, Phys. Rev. D74:054022, Combinatorial background is parameterized as just a constant. Unbinned ML fit to signal Dalitz plots 21

22 Results: Y(5S) Y(1S) Y(1S)π + π - χ2 = 52.1/56 χ2 = 54.9/48 χ2 = 62.3/56 M(ϒ(1S)π + ) and M(ϒ(1S)π - ) projections: χ2 = 58.0/63 χ2 = 61.5/62 signals M(ϒ(1 S)π + ), GeV M(ϒ(1S)π - ), GeV reflections 22

23 Results: Y(5S) Y(2S) Y(2S)π + π - χ2 = 62.5/54 χ2 = 48.9/45 χ2 = 65.4/53 M(ϒ(2S)π + ) and M(ϒ(2S)π - ) projections: signals χ2 = 57.7/52 χ2 = 57.1/54 reflections M(ϒ(2S)π + ), GeV M(ϒ(2S)π - ), GeV 23

24 Results: Y(5S) Y(2S) Y(2S)π + π - 24

25 Results: Y(5S) Y(2S) Y(2S)π + π - 25

26 Results: Y(5S) Y(3S) Y(3S)π + π - χ2 =18.9/26 χ2 =51.9/38 χ2 =25.1/26 M(ϒ(3S)π + ) and M(ϒ(3S)π - ) projections: χ2 = 41.3/36 χ2 = 22.4/33 M(ϒ(3S)π + ), GeV M(ϒ(3S)π - ), GeV 26

27 Summary of Results on Z b Masses & Widths Masses, widths and relative amplitudes from five channels are consistent. Relative phases are swapped for final states ϒ and h b Z b (10610): M= ±2.0 4±20MeV Z b (10650): M= ±1.5 MeV Γ=15.6±2.5 6±25MeV Γ=14.4±3.2 MeV 27

28 Angular Analysis Expected angular correlations for ϒ(5S) Z b π 1 [ϒ(nS) π 2 ] π isotropic λ beam direction 2 neglect Z b recoil motion (β<0.02 very good approximation) (formulae for modes with h b are also available) θ 1, θ 2 polar angles of 1 st and 2 nd pions ϕ p angle btw planes defined by (1) π 1 & Z axis, (2) π 1 & π 2 θ ππ angle between two pions 28

29 Angular Analysis Consider 1D projections. Interference terms vanish (except for cosθ ππ ) after integration over other angular variables subtraction of non resonant contribution is possible. Best discrimination is provided by: cosθ 2 for 1 and 2 ; cos θ 1 for 2 + Example: ϒ(5S) Z b + (10610) π [ϒ(2S)π + ] π Color coding: J P = (0 ± is forbidden by parity conservation) 29

30 Angular Analysis Summary Probabilities at which various J P hypotheses are disfavoured compared to assignment is favourable. 1 -, 2 +,2 - are disfavoured at typically 3σ level. Confidence Levels of angular fits to ϒ(5S) Z b+ π [h b (1P)π + ] π decay with hypothesis

Possible Nature of Z b States B*B and B*B* S wave molecules arxiv:1105.

of Z b are close to B*B(*) thresholds b Quantum numbers J P =1 + Amplitude ratio

Explains why h b ππ is unsuppressed relative to ϒππ Neutral partners of Z b should

31 Possible Nature of Z b States B*B and B*B* S wave molecules arxiv: Z Z ' b b = = bb bb 1 1 Qq Qq bb bb 0 0 Qq Qq Masses of Z b are close to B*B(*) thresholds b Quantum numbers J P =1 + Amplitude ratio A[Z b (10610)] / A[Z b (10650)] ~1 Relative phase ~0 for ϒ and ~180 for h b Explains why h b ππ is unsuppressed relative to ϒππ Neutral partners of Z b should exist Measurements in B*B and B*B* modes should be done Existence of other molecular states is predicted 31

32 Summary h b (1P) and h b (2P) bottomonium states are observed for the first time. Masses are consistent with expected ones COG arxiv: First observation of two charged bottomonium like charged resonances. Z b (10610) Z b (10650) M = ± 2.0 MeV Γ = 15.6 ± 25MeV 2.5 M = ± 1.5 MeV Γ = 14.4 ± 3.2 MeV arxiv: Both Z b are seen in 5 different final states with consistent parameters. Masses are close to B*BB and B*B* B thresholds J P =1 + assignment is favorable; other J P are disfavored at about 3σ level Amplitude ratio A[Z b (10610)] / A[Z b (10650)] ~ 1. Relative phase is ~0 for modes with ϒ and ~180 for ones with h b. 32

33 Fits to MM(π + π ) spectra in MM(π) bins h b ϒ(2S)

34 Search in ϒ(4S) data ϒ(1S) h b ϒ(2S) ISR ϒ(2S) ϒ(1S) π + π no h b (2P) h b L = 711fb 1 [ 6 ϒ(5S) sample] No significant signal of h b (1P): (34±20) 10 3 (1.7σ) σ[e + e - h b (1P) π + π - ϒ(4S) σ[e + e - h b (1P) π + π - ϒ(5S) <0.28 at 90%C.L. 34 ϒ(4S) does not exhibit anomalous properties

35 Reflection from K S π + π Ks M(π+ +π-) kinematic boundary Ks generic MC Data ϒ(3S) MM(π+π-) Fit to M(π + π ) in MM(π + π ) bins K S yield from data example 35 M(π+π-) MM(π+π-)

Bottomonium results at Belle

Bottomonium results at Belle A.Kuzmin BINP For Belle Collaboration Hadron 2011, June 14, 2011 1 PRL100,112001(2008) Puzzles of ϒ(5S) decays At 21.7 fb 1 ϒ (5S) >ϒ(nS) π+π two orders of magnitude larger