Hyperons production in Y(1,2,3S) annihilation at Belle

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1 Hyperons production in Y(1,2,3S) annihilation at Belle Umberto Tamponi Second Year Seminar 02/17/2015 1

2 The Belle detector Calorimeter Inner tracking: 3 4 layers of Double Sided Silicon Strip Drift chamber (traking + de/dx) Particle Identification: Time of flight (TOF) Threshold Cherenkov counter Neutrals: NaI(Tl) calorimeter RPC + Fe for KL conversions PID Drift Chamber Silicon vertex 2

3 The Datasets For a summary of Belle's results: arxiv: v1 e e+ ~8 GeV Y(1S) 5.7 fb 1 R Y(2S) 24 fb 1 1 quarkonium states produced at rest ~3.5 GeV Y(3S) 3 fb 1 Off 89 fb 1 Y(4S) 711 fb 1 Y(5S) 121 fb 1 ~ 1 ab of e+e events World largest samples of Y(1S), Y(2S), Y(4S), Y(5S) and off resonance ~ 770 M of of Y(4S) BB events 3

4 Belle's enviroment Occupancy at Y(4S) Average multiplicity Hadronic Trigger rate Tau Trigger rate: 8 10 tracks ~ 0.5 khz ~ 1 khz Effective cross sections depend on beam energy spread and few other parameters Y(1S) Y(2S) Y(3S)Y(4S) Y(5S) Continuum is the main background for almost every energy 4

5 Introduction Bottomonium and its recent developments 5

6 Quarkonium: the general picture I = 0 (no charged partners) CP eigenstates Not relativistic Bound state of two heavy quarks S1 S2 Confinement BOTTOMONIUM Mass [GeV] L <v2(c)> ~ 0.3 c2 <v2(b)> ~ 0.1 c2 Non-relativistic potential 11 Y(6S) 10.8 Unresolved triplets Observed states Y(5S) 10.6 η (4S) Y(4S) b χbj (3P) Y(21D) Y(13DJ ) Y(11D) Y(2 DJ ) Y(3S) 1 gluon exchange h b (3P) η (3S) b 10.2 h b (2P) χbj (2P) 10 Y(2S) η (2S) b Small radius! 9.8 hb (1P) χbj (1P) 9.6 Theoretical predictions from Eur. Phys. J. C72 (2012), Issue 4, Y(1S) η (1S) b JP C 1 3 S1 0 1S + 0,1, P0,1, P1 + 1,2,3 3 D1,2, D2 6

7 Spin structure Eichten and Feinberg, PRD23, 2724 (1981) L S1 Mass [GeV] Long range term (spin orbit) Short range term (spin spin) S2 Non-relativistic potential 11 Y(6S) 10.8 Unresolved triplets Observed states Y(5S) 10.6 η (4S) Y(4S) b χbj (3P) 10.4 h b (3P) 3 Y(21D) Y(13DJ ) Y(11D) Y(2 DJ ) Y(3S) η (3S) b 10.2 h b (2P) χbj (2P) 10 Y(2S) η (2S) b If this is true 9.8 hb (1P) χbj (1P) Fine splitting Hyperfine splitting 9.6 Theoretical predictions from Eur. Phys. J. C72 (2012), Issue 4, Y(1S) η (1S) b JP C 1 3 S1 0 1S + 0,1, P0,1, P1 + 1,2,3 3 D1,2, D2 7

8 Quarkonium: the general picture Naively: transitions from above the theshold to narrow states are negligible OZI rule b b b Mass [GeV] u u b 11 BOTTOMONIUM Bro a innon-relativistic to d stat potential ~ 1 ope es: Unresolved tripletsd 00 % n flav ecay o Observed states ur Y(6S) 10.8 Y(5S) 10.6 η (4S) Y(4S) b u Y(3S) u d d u Y(21D) 3 η (3S) b h b (2P) χbj (2P) u b h b (3P) Y(2 DJ ) 10.2 b χbj (3P) Na Y(1 D ) Y(1 D) r wit row s ht h (1P) ran tates a χ (1P) nn ha ihilat sition : dec dro ay s i ns ons in or Theoretical predictions from lig Eur. Phys. J. C72 (2012), Issue 4, h 1981 t 1 J 10 Y(2S) η (2S) b b 9.8 bj Y(1S) η (1S) b JP C 1 3 S1 0 1S + 0,1, P0,1, P1 + 1,2,3 3 D1,2, D2 8

9 Mass [GeV] Bottomonium selection rules Non-relativistic potential 11 Y(6S) 10.8 Unresolved triplets 10.6 η (4S) Y(4S) b χbj (3P) 10.4 h b (3P) 3 Y(21D) Y(13DJ ) Y(11D) Y(2 DJ ) Y(3S) η (3S) b 10.2 h b (2P) χbj (2P) 10 Y(nS) (mp) Electric dipole h(np) (ms) Observed states Y(5S) transitions carry J=1 Y(nS) Y(mS) FORBIDDEN Y(nS) (ms) Magnetic dipole Y(2S) η (2S) b 9.8 h b (1P) χbj (1P) 9.6 Theoretical predictions from Eur. Phys. J. C72 (2012), Issue 4, Y(1S) η (1S) b JP C 1 3 S1 0 1 S0 + 0,1,2+ 3 P0,1, P1 + 1,2,3 3 D1,2, D2 9

10 Mass [GeV] Bottomonium selection rules Non-relativistic potential 11 Y(6S) 10.8 Unresolved triplets 10.6 η (4S) Y(4S) b χbj (3P) 10.4 Y(21D) 3 Y(3S) B[Y (2 S) ηy (1 S)] B [Y (2 S) π π Y (1 S)] h b (3P) Y(2 DJ ) η (3S) b 10.2 CLEO '08 h b (2P) χbj (2P) PRL 101, (2008) Y(13DJ ) 10 Y(nS) Y(mS) Spin preserving Y(nS) h(mp) Spin flipping Observed states Y(5S) Heavy quark spin is preserved Y(2S) Y(11D) BaBar '11 η (2S) PRD 84 (2011) b 9.8 h b (1P) χbj (1P) Belle '12 PRD 87 (2013) QCDME Theoretical predictions from Voloshin 2008 Eur. Phys. J. C72 (2012), Issue 4, Y(1S) QCDME η (1S) b JP C 1 3 S1 Kuang S0 + 0,1,2+ 3 P0,1, P1 1,2,3 3 D1,2, D R [x 10 ] 10

11 Progresses: breaking the rules... PRL108, simultaneous discovery of hb(1,2p) Combinatorial background subtracted Y(2S) Y(1S) Y(3S) Y(1S) 11

12 ... the exotica... PRL108, P Zb Z'b The heavy quark spin flip is predicted to suppress the hb transition No suppression Intermediate state? Look at hb yield in bins of M( hb) (Missing mass from ) 2P Zb Z'b Y(5S) Z'b Zb hb(2p) hb(1p) The transition is mediated by an intermediate charged state 12

13 .. the η b(ns)... PRL 109, (2012) 2P 1S 15 2P 2S 4.2 1P 1S 9 M[ b(1s)] = ( ± 1.5 ± 1.8)MeV [ b(1s)] = ( )MeV B[hb(1S) b(1s)] = 49.2 ± 5.7 % B[hb(1S) b(2s)] = 22.3 ± 3.8 % M[ b(2s)] = ( ± )MeV [ b(2s)] < 24 MeV B[hb(2S) b(2s)] = 47.1 ± 10.5 % +4.0 MHF(2S) = MeV 13

14 and the contribution from Torino Y(4S) hb(1p) hb(1p) b(1s) Y(4S) hb(1p) hb(1s) First single meson, 3S 1P transition observed with > 5 Y(1S) = 4 KeV Y(1S) = 1.7 KeV hb(1p) = 37 KeV No intermediate states One order of magnitude larger than any other Y(4S) transition BF[Y(4S) hb(1p)] = ( )x10 3 MHF( b) = ( ) MeV Presented at Moriond2014, DIS2014, QWG2014, QCHSXI b To e to P d i tte m sub RL 14

15 S) Y(n hbr. av g.) vg.) 00 2 y nar v. a v (pri (pri limi ) 9) 200 ) 008 ( ( 4 ( Pr e tive tive ad i a ia Rad le Bel PRL 0 81, RD le Bel ar P BaB 03 1, , PRL P RD 30 Potential pnrqcd ar BaB O CLE 004 1S Hyperfne splitting [MeV/c 40 ne Mei s Aart t Al. ch e 012 Bur Al l et l 20 wal Rod Tian 2 t al hl e Knie pk o, Re 7 fo r d 2 00 Rad p ko, Re 3 fo r d 20 1 Rad t al ao e i Zh We 3.7 discrepancy 80 Lattice 20 Y(2,3S) b(1s) 2 ] 90 hb(1p) b(1s) 1S hyperfine splitting hb(1,2p) b(1s) 15 15

16 Second part The production of hyperons in Bottomonium annihilations at Belle 16

17 Quarkonium annihilations: Y(1,2S) Yang Landau theorem: A Vector cannot decay into an even number of massless Vectors Y(1S) as a paradigm Hadronic events Y(1S) gg 2.2% Y(1S) ggg 82% b b b b Y(1S) qq 8.3% b q b q Leptonic events Y(1S) l+l 7.5% e+, +, + b b e,, Y(2S) (7.2%) Hadrons (52.2%) (25%) J(1P) (6.9%) (3.8%) (34%) J(1P) J(1P) Had. (98.3%) Hadrons (92.5%) Had. (81%) Had. (66%) (1.7%) Y(1S) (19%) Y(1S) radius ~ 0.2 fm Y(1S) mass: GeV Gluon density ~ 100 GeV/fm3 Realistic? 17

18 The Hyperon family Foundamental states in the representantion S= 3/2 S= 1/2 diquark representation Scalar diquark = (ud)0 + s1/2 = (ud)1 + s1/2 L s1/2 (ud)0 Vector diquark = (ss)1 + q1/2 = (ss)1 + s1/2 18

19 Y(1,2S) ggg : hyperons CLEO collaboration, PRL53, 1, (1984) Ratio /K in continuum and in Y(1S) Y(1S) qq x = 2 p / s us (ud)s (ud)s (ds)s Diquark are more easily produced by ggg fragmentation 19

20 Y(1,2S) ggg : hyperons CLEO collaboration, PRL53, 1, (1984) Argus collaboration, Z Phys C, 9, (1988) Ratio /K in continuum and in Y(1S) Y(1S) qq x = 2 p / s Suppression of spin 3/2 states Diquark are more easily produced by ggg fragmentation 20

21 Hyperons : ggg VS qq Hyperon production is enhanced in Y decays with respect to the nearby continuum and is large. Enhancement for baryon B : BF(Y(1S) + X ) ~ 10% [e+e Y(nS) B +X] BF(Y(1S) + X ) ~ 3% [e+e qq B +X] Phys.Rev.D76, Phys.Rev.D76, CLEO CLEO DATA MC 21

22 The H dibaryon Can an exotic state explain the high production of hyperons in Y(nS) annihilation? H dibaryon (Jaffe, 1977) completely antisymmetric arrangement of uuddss H H p, H p d s u d s u 22

23 Search for H dibaryon PRL 110, (2013) Analysis strategy: Inclusive reconstruction in Y(1S) and Y(2S) sample Decays with H H p, H p PRL 110, No unstable H dibaryon has been found at Belle Preliminary (2013) How to understand the inclusive production? Investigate exclusive annihilation modes 23

24 Y(1,2S) exclusive annhilations Belle has 100 Million of Y(1S) an 150 Million Y(2S) Can we better understand the hyperon production from the exclusive final states? Search for + long living particles Caveat: Conservation of Charge, B and S Y(1S) DATA pp, K+K, pairs only the distribution of # of charged tracks per event suggests to investigate the states with tracks (3 channels) tracks (6 channels) tracks (10 channels) Continuum contribution must be subtracted for each channel using a sample taken at s = GeV s indipended observable are needed Selection criteria: pair charge balance tracks and gamma quality Event closure pt)< 50 MeV, in each channel. 24

25 and selection decay with a clear V topology in the detector momentum resolution momentum resolution VS polar angle 10% resolution 1% resolution p = 1.5 MeV momentum [GeV] cos (67.8%) = 2.3 MeV (~100%) = 2.5 MeV 25

26 Y(2S) analysis Hadronic transition of Y(1S) if( with M_rec MY1S < 15 MeV) remove the event bj(1p) tag Y(2S b2 b1 b0 An event is selected as candidate if there is photon in the b0, b1 or b2 range ( MeV) < XT < Y(1S recoil mass in Y(2S) events 26

27 Signal fit Continuum qq sample is studied using a 79/fb sample collected below the Y(4S), properly rescaled Peak: Gaussian function Y(1S) width makes the radiative correction impact on the resolution negligible For the bj(1p) we fit the energy distribution for the tagged events Hadronic Momentum b0(1p) 27

28 Y(1,2S) exclusive + X Preliminary X = combination of,, pp and Max 9 bodies, Max one 48 channels X BF [Y (1S) X ] 2 x 10 4 X BF [Y (2S) X ] 0.7 x 10 4 First observation of Y(nS) exclusive decays with hyperons BF ratio (th. Prediction = 0.77) 28

29 Resonant substructures Preliminary Analysis of the K and KK invariant mass in reconstructed events no dominant resonant processes 29

30 interaction Dynamical interaction within the pair Statistical significane of the deviation form the phase space flat hypothesys of M( ) 30

31 Y(1,2S) exclusive + X: summary Preliminary be o T to P d i tte m sub RD 31

32 Future prospects Universal trend in baryon production from qq fragmentation Pei, Z Phys C 72 (1996) Baryon binding energy Normalization ( s enters here) Spin counting EB T 2 J +1 N N =C (γ s ) e CB s Meson to Baryon normalization Mass [GeV] Strangeness Suppression factor Hadronization temperature 32

33 Future prospects Universal trend in baryon production from qq fragmentation Pei, Z Phys C 72 (1996) Y(1S) ggg? Baryon binding energy Normalization ( s enters here) Spin counting EB T 2 J +1 N N =C (γ s ) e CB s Meson to Baryon normalization Mass [GeV] Strangeness Suppression factor Hadronization temperature 33

34 Excited hyperons uds) uds) 1/2+ 1/2 1/2+ 3/2 1/2 3/2+ 3/2 sss) dss) 1/2+ 5/2 3/2 3/2+ 3/2+ K K L=0 L=1 L=0 L=1 L= angular momentum between the quark and the diquark J = L + Squark Dominant decays only L=0 L=1 L=0 34

35 Future prospects Preliminary studies conducted at Y(1S) energy 35

36 Future prospects Argus 1988 r= Hyperons per Y(1S) hadronic event Hyperons per qq hadronic event Future plans (work in progress) Inclusive production rates of spin ½ and spin 3/2 states from Y(nS) Differential spectra with deconvolution of the detector acceptance and resolution (first time) Study of the associated production and the Hyperon Hyperon correlation functions 36

37 Summary of the activities Spectroscopy First observation of Y(4S) hb(1p) and new measurement of the b(1s) parameters paper in internal review (to be submitted to PRL) First observation of Y(5S) Y(1D) not covered in this presentation (see the backup) paper in preparation (to be submitted to PRD(rc)) Hyperon production First observation of exclusive Y(1,2S) +X annihilations paper in internal review (to be submitted to PRD) Service work (for BelleII) Construction of the laser calibration system for the BelleII Time of Propagation counter Preparation and Validation of the Y(nS) MC generators for the BelleII experiment (responsible person) Tuning of the Pythia8 fragmentation parameters for ggg and qq final states (responsible person) 37

38 Summary of the activities Conference talks (on behalf of the Belle Collaboration) EPS HEP 2012: Y(2S) transitions and decays at Belle ICFP 2012: Quarkonium like states at Belle DIS 2012: Bottomonium like states at Belle Moriond 2013 QCD : Study of Baryons in B decays and e+e production at BaBar and BELLE Quarkonium 2013: Bottomonium decays at Belle HEP MAD 2013: Recent QCD results from Belle DIS 2014 : Spin effects in Bottomonium at Belle Quark confinment 2014: Recent Bottomonium results from Belle Quarkonium 2014: Bottomonium like spectroscopy an transitions at Belle Seminars (not on behalf of the Belle Collaboration) HASPECT week 2014 : Exprimental techniques for Bottomonium physics 38

39 Backup

40 Super KEKB

41 Belle II

42 Belle II PID Challenging time resolution (100 ps)

43 BB interaction: the B meson decays B Baryon anti Baryon + X has large BF (6.8 %) and non trivial phenomenology Near threshold enhancement Baryon anti baryon pair (BB) is produced near BB threshold B ppk + + B0 ppk0 B+ p The short distance model (J.Phys.G34: , 2007): High M(BB) requires an highly off mass shell gluon, and thus is suppressed M(BB) enhancement Low multiplicity is suppressed Wrong angular distribution in B+ ppk+ The short distance model is not enough Purely dynamical effects or something more?

44 Charged track selection PID with atc_pid likelihood ratio Pion: atc_pid(p pi)<0.4 && atc_pid(k pi)<0.4 Proton: atc_pid(p pi)>0.6 && atc_pid(p K)>0.6 Kaon: atc_pid(k p)>0.6 && atc_pid(k pi)>0.6 Primary vertex cut: Dr < 1.5 cm && Dz < 5 cm Generic MC atc_pid(i j) = L(i)/(L(i)+L/(j)) ~ 1 if PID = i ~ 0 if PID = j atc_pid(i j) = 1 atc_pid(j i) The event is discarded if either or combined with a or K, reconstructs a or an (within 3 sigma) Generic MC

45 selection Standard values match == 0 E9/E25 > 0.9 shower width < 5.8 cm Optimized with Generic MC N_hits E_min Generic MC E_cm > 50 MeV 0 are reconstructed as pairs with m( ) m( 0) < 15 MeV Generic MC N_hits>= 2

46 0 selection A = E1 E2 /(E1+E2) pi0 is scalar flat energy distribution in boosted frame Optimal A thresolds: p* < 0.3 GeV : A < 0.76 p* > 2.2 GeV : A < GeV < p* < 2.2 GeV: optimization in bins of 0.2 GeV linear extrapolation of the optimal value Pi0 selection results: Solid: Real pi0 Open: Combinatorial

47 Feeddown from misrecontruction States with higher multiplicity can be partially reconstructed as states with lower mult Feeddown MC MC Signal events Data Feedback suppression: pt < 50 MeV, in each channel.

48 The KEKB B-factory ~8 GeV ~3.5 GeV CM energy: GeV Beam energy spread: 5 MeV Crab crossing head on collisions with finite crossing angle Current Luminosity World record

49 Hadronic transitions: lower states Kuang, Front.Phys.China 1, 19 (2006) QED multipole expansion term: a/ ~ ak < 1 In quarkonia: r ~ 0.1 fm k ~ 100 MeV rk < 1 a b r Photon momentum k B[Y (2 S) ηy (1 S)] B [Y (2 S) π π Y (1 S)] b Gluon Radius (potential model) hep-ph/ (QUARKS-2004) -1 r [ MeV ] momentum k P D 2P PRL 101, (2008) 1P BaBar ' MeV PRD 84 (2011) S 2D 2S Belle ' MeV PRD 87 (2013) QCDME 500 MeV 1S Voloshin MeV kxr=1 Frascati Phys.Ser. 46 (2007) S CLEO '08 QCDME Kuang Mass [GeV/c ] R [x 10 ] 2

50 Hadronic transitions: Y(5S) b quark spin flip no b quark spin flip Spin flip prediction Experiment Γ [Y (ns) η Y (ms)] 1 Γ[Y (ns) π π Y (ms)] Γ[Y (5 S) π π hb (2 P)] =0.77± Γ[Y (5 S) π π Y (2 S)] Γ[Y (ns) π π h b (mp)] 1 Γ[Y (ns) π π Y (ms)] Γ[Y (5 S) π π hb (1 P)] 0.07 =0.46± Γ[Y (5 S) π π Y (2 S)] PRL108, No suppression ± 1.5 MeV Z'b Zb Z'b B*B* ± 0.4 MeV Zb BB * 2 ± 2 MeV ± 2 MeV 2 ± 2.2 MeV ± 0.4 GeV Γ [Y (5 S) ηy (1 S)] Belle =0.16 Γ[Y (5 S) π π Y (1 S)] preliminary Γ [Y (5 S) ηy (2 S)] =0.48 Γ[Y (5 S) π π Y (2 S)] No suppression 3

51 Hadronic transitions: Y(4S) Mass [GeV] Γ [Y (4 S) ηy (1 S)] =2.41±0.40±0.20 Γ[Y (4 S) π π Y (1 S)] Spin flipping enhanced transition PRD 78, Non-relativistic potential 11 NR potential + Coupled channel Y(6S) Unresolved triplets 10.8 Observed states Y(5S) 10.6 Light quark dynamics is not negligible in both transitions and spectra η (4S) Y(4S) b χbj (3P) 10.4 h b (3P) 3 Y(21D) Light quark dynamics dominates over spin symmetry effects Y(13DJ ) Y(11D) Y(4S) hb(1p) Guo, PRL 105 Predicted as large as 10 3 (2010) Y(2 DJ ) Y(3S) η (3S) b 10.2 h b (2P) χbj (2P) 10 Y(2S) η (2S) b 9.8 h b (1P) χbj (1P) 9.6 Theoretical predictions from Eur. Phys. J. C72 (2012), Issue 4, Y(1S) Spin flipping suppressed Spin flipping non suppressed Missing information Y(5S) hb(1p) Y(5S) hb(2p) No predictions η (1S) b JP C 1 3 S1 0 1 S0 + 0,1,2+ 3 P0,1, P1 + 1,2,3 3 D1,2, D2 4

52 Y(5S) bb M( ) in data 121 fb 1 of e+e collisions at Y(5S) energy Reconstructed Y(5S) Belle Preliminary bb Belle Preliminary Y(2S) hb(1p) Y(1D) hb(2p) 5

53 Y(5S) bb Γ [Y (5 S) ηh b (1 P)] <0.94 Γ[Y (5 S) π π hb (1 P)] BF[Y(5S) Y(2S)] = ( ) x 10 3 BF[Y(5S) Y(1D)] = ( ) x 10 3 BF[Y(5S) hb(1p)] = < 3.3 x 10 3 BF[Y(5S) hb(2p)] = < 3.7 x 10 3 (90% CL) (90% CL) Combinatorial background subtracted Belle Preliminary hb(1p) Γ [Y (5 S) ηh b (2 P)] <0.62 Γ[Y (5 S) π π hb (2 P)] Y(1D) Y(2S) hb(2p) 6

54 Y(4S) bb Belle Preliminary Combinatorial background subtracted First single meson, 3S 1P transition observed with > 5 BF[Y(4S) hb(1p)] = ( )x10 3 Y(1S) = 4 KeV Y(1S) = 1.7 KeV hb(1p) = 37 KeV One order of magnitude larger than any other Y(4S) transition 7

55 Probing the spin structure Hyperfine splitting = M(triplet) M(singlet) Spin interaction term: P wave Odd r (0) 2 = 0 MHF(1P) = MeV/c2 MHF(2P) = MeV/c2 S wave Even r (0) 2 0 1P Hyperfine splitting 1S Hyperfine splitting pnrqcd: MeV/c2 Kniehl et al., PRL92,242001(2004) Lattice: 60 8 MeV/c2 Meinel, PRD82,114502(2010) PDG 12 : MeV/c2 8

56 Detecting spin singlets Signal MC simulation MC b hb Y(4S) b hb Belle Preliminary b(1s) = ( ) MeV b(1s) = ( ) MeV BF[hb(1P) b(1s)] = ( 52 4) % 10 MHF( b) = M( b) M(Y(1S)) = ( ) MeV Assuming Y(1S) mass = MeV 9

57 transitions: Th. VS Exp Y(2,3S) Y(4S) transitions Y(5S) transitions 9 9

58 1S HF splitting cc VS bb hb(1p) b(1s) M( b)m1 M( b)e1 = 12 3 MeV hb(1,2p) b(1s) 3.7 discrepancy M( c)m1 M( c)e1 = MeV M( c)line shape factor: 2 E 3γ exp( E 2 γ /(8 β )). priv E1 (.) a vg.) av g r el. le P Bel 1) 20 (201 8) le Bel (200 ) 30 v. (pri M1 ar BaB 10) 40 ( ar ( BaB 60 O CLE 1S Hyperfne splitting [MeV/c 2 ] Y(2,3S) b(1s) (2S) / J c(1s) uncorrected = MeV PRL 102 (2009) , Erratum ibid. 106 (2011) fusion B decays Same factor for the b(1s)? 2) 201 III ( BES ) 009 O (2 CLE 2) 201 III ( BES ) 009 O (2 CLE 03) ( 20 BES 00) ( 20 BES 00 ) ( 20 BES 1) 201 le ( 8) Bel 200 ar ( BaB 2) 201 le ( 11) Bel ( 20 ar BaB 10) ( 20 8) ar 200 BaB le ( Bel 4) 200 O ( CLE hc(1p) c(1s) (2S) / J c(1s) corrected 58 10

59 Y(5S) lineshape history PRL 100, (2008) 21.7 fb 1 at GeV PRD 89, (2010) ~1 fb 1/point SCAN Y(5S) Y(6S) Y(5S) (a.k.a. Yb) PRL 102, (2009) BaBar Belle 2010 M(5S)bb = MeV M(5S) = MeV M(5S) M(5S) = 9 4 MeV 11

60 Belle Y(5S) scan Full Belle scan For Rb: 61 points (50/pb each) every 5 MeV For R : 22 points (1/fb each) Both open and close [e e bb hadrons] Rb = [e+e ] + e+e qq suppression: R2 D. Santel, LLWS 2014 According to PRL 102, (2009) cross sections are visible ones, not Born + [e e Y(nS)] R = [e+e ] e+e + suppression: sidebands D. Santel, LLWS

61 Rb at Belle Same as PRL 102, (2009) Coherent continuum Amplitude Y(5S) relativistic Breit Wigner Y(6S) relativistic Breit Wigner According to BaBar's analysis,continuum is assumed to be flat Incoherent continuum Amplitude M(5S)bb = MeV Y(5S) fitted mass Y(5S) fitted mass preliminary (5S)bb = 51 2 MeV BaBar, same fit M(5S)bb = MeV M(6S)bb = MeV Rb maxima (6S)bb = 40 2 MeV 13

62 R at Belle No continuum contribution is visible preliminary Y(1S) Fixed by Rb Y(6S) Y(1,2,3S) First Evidence M(5S) = ± 1.4 ± 1.2 MeV (5S)bb = 51 ± 5 ± 5 MeV Y(2S) Belle 2010: M(5S) = MeV M(5S) M(5S)bb = 4.4 ± 2.5 MeV (1.8 ) (5S) (5S)bb = 0 ± 8 MeV Y(3S) Y(5S) mass Y(6S) mass 14

63 Rb versus R Rb an R are not independent Rb includes contribution form Y(nS) Rb includes contribution form hb(np) Pb = A5S(bb) x BW(5S) 2 bb contribution Y(nS) P( ns) = PHSP x A5S(nS) x BW(5S) 2 contribution Adding Y(5S) h (1,2P): P( bb) = (33 ± 7.5) % of Pb Assuming Isospin simmetry: P( bb) = (50 ± 14) % of Pb Adding Z B B : P( bb + Zb) = (132 36) % of Pb From R : P( ns) = (20 ± 6) % of Pb b (*) (*) b No or little room for Y(5S) BB*, BB, B*B*, BsBs direct decays these events come either from continuum, or from Zb decay Small interference between Y(5S) and continuum (different final states) Large interference Flat continuum is a crude approximation Resonance parameters from R are likely more reliable 15

64 Exotic Quarkonia Since 2009 we observe some states that are not neutral decay in conventional quarkonium with single pion transitions Molecule? Q Q Must contain two heavy quark (quarkonium like part) + 2 light quarks Tetraquark? q Q Q q q q 2009: Zc(4430) 2009: Z1 and Z : Zb and Z'b 2013: Z(3895) In this talk Molecule Tetraquark Mass close to open thresholds (DD, DD*, BB*...) No prediction (open flavour ) >> (narrow quarkonium) (open flavour ) ~ (narrow quarkonium) 4

65 hb(1,2p) from Υ(5S) PRL108, PRL108, Inclusive search : e+e Υ(5S) π π + X (inspired by e+e ψ(4170) π π Cleo) simultaneous discovery of hb(1,2p) Missing Mass Measured M(miss) = (Ec.m. E* )2 p2 Known Y(5S) M(miss) In Di pion transition: M(miss) = M(lower state) U.Tamponi, Bottomonium( like) states at Belle ICFP2012 4

66 hb(1,2p) from Υ(5S) PRL108, PRL108, simultaneous discovery of hb(1,2p) Combinatorial background subtracted Y(2S) Y(1S) Y(3S) Y(1S) U.Tamponi, Bottomonium( like) states at Belle ICFP2012 5

67 hb(1,2p) from Υ(5S) PRL108, PRL108, hb(np) is the singlet partner of (np) Hyperfine Splitting: M(singlet) M(triplet) MHF(nP) = M(hb(nP)) MAVG( (np)) simultaneous discovery of hb(1,2p) MAVG( (1P)) = (M b0 + 3 M b1 + 5 M b2) / 9 Spin averaged mass ΔMHF(1P) = 0.8±1.1 MeV/c2 Precise measurement Study ΔMHF(2P) = 0.5±1.2 MeV/c2 of spin effects in QCD U.Tamponi, Bottomonium( like) states at Belle ICFP2012 6

68 hb(1,2p) mass: Zb PRL108, P Zb Z'b The heavy quark spin flip is predicted to suppress the hb transition No suppression Intermediate state? Look at hb yield in bins of M( hb) (Missing mass from ) 2P Zb Z'b Y(5S) Z'b Zb hb(2p) hb(1p) U.Tamponi, Bottomonium( like) states at Belle ICFP2012 The transition is mediated by an intermediate charged state 7

69 Zb in Y(nS) final states PRL108, Y(nS) Clean final state Pure Y(nS) sample recoil tag 3 other observations of Zb's! PRL108, Belle has discovered two charged resonances: Zb bottomonium like simultaneous discovery of hb(1,2p) The states are observed in 5 final states, all with consistent masses, close to the BB* and B*B* threshold. M2(Y(1S) ) Analysis of angular distributions suggests JP=1+ for these states. U.Tamponi, Bottomonium( like) states at Belle ICFP2012 ArXiV:hep ex/ , to PRL 8

70 Zb Summary PRL108, Mass and measured in 5 different final states agree Angular analysis suggests JP = 1+ Zb(10610) M = ± 2.0 MeV = 15.6 ± 2.5 MeV Zb(10650) M = ± 1.5 MeV = 14.4 ± 3.2 MeV U.Tamponi, Bottomonium( like) states at Belle ICFP2012 The Di Pion transitions from the Y(5S) proceed via the intermediate charged state Zb The transition does not imply spin flip Masses are close to B*B and B*B* theresholds Molecules? The Y(5S) is an unexpected source of hb 9

71 hb (1P,2P) η b (1S,2S) arxiv: PRL108, hb(1,2p) is predicted to have large BF BF[hb(1P) ηb(1s)] = 41% BF[hb(2P) ηb(1s)] = 13% BF[hb(2P) ηb(2s)] = 19% Zb for radiative decays to ηb JP=1+ O(104) larger than in the Y(nS) system simultaneous discovery of hb(1,2p) Clean experimental signature with the hb(1,2p) and Zb tagging Means Less background than in the inclusive searches from Y(2,3S) Y(3S) γ η b (1S) U.Tamponi, Bottomonium( like) states at Belle ICFP

72 Search for the η b (1,2S) PRL108, arxiv: JP=1+ Zb simultaneous discovery of hb(1,2p) hb not reconstructed Missing mass analysis: miss miss miss hb U.Tamponi, Bottomonium( like) states at Belle ICFP2012 Y(5S) b hb Zb tag requested 11

73 Spin-parity of the Zb Preliminary New study of spin parity with a 6 D fit that includes contributions from non resonant S and D waves: S(s1,s2) = A(Zb) + A(Z'b) + A(f0(980)) + A(f2(1275)) + A(NR)+ A( ) Breit Wigner Flatte Breit Wigner Breit Wigner c1 +c2m2( ) Fit projections in M(Y(nS) ) 1+ is assigned unambiguously 6

74 Zb decay modes Y(5S) arxiv: v2 Reconstructed part BB* Zb B* B*B* Recoil mass from B* system tags the other B Zb Z'b BB* Z'b B(*) Not reconstructed B*B* Z'b Recoil mass form single pion in selected events 7

75 Zb decay modes arxiv: v2 Z'b B*B* Zb BB * From inclusive Y(5S) +X decays Kinematically favoured but absent Why Zb(10650) should not decay in BB*? Molecular Model Zb ~ BB *> Z'b ~ B*B* > with negligible BB*> component Proximity to open threshold (open flavour ) >> (narrow quarkonium) The Zb are BB* and B*B* molecules with JP = 1+ (?) 8

76 Search for Zb0 arxiv: Y(5S) Y(nS) e+e, BF[Y(5S) Y(1S)] = (2.25 ± 0.11 ± 0.20) x 10 3 BF[ ] = (4.45 ± 0.16 ± 0.35) x 10 3 BF[Y(5S) Y(2S)] = (3.79 ± 0.24 ± 0.49) x 10 3 BF[ ] = (7.97 ± 0.31 ± 0.96) x 10 3 BF[Y(5S) Y(3S)] = (2.09 ± 0.51 ± 0.34) x 10 3 BF[ ] = (2.88 ± 0.19 ± 0.36) x 10 3 Isospin symmetry : BF[ ] = 2x BF[ ] OK 9

77 Search for Zb0 arxiv: Again multidimensional fit that includes contributions from non resonant S and D wave S(s1,s2) = A(Zb) + A(Z'b) + A(f0(980)) + A(f2(1275)) + A(NR) Significance is calculated from the Multi dimensional fit Z0b(10610): 6.5 [4.9 from Y(2S) from Y(3S) ] Observed Z0b(10650): not observed but not excluded either 10

78 Discovery of Zc(4430) B0 Belle: PRL100, (2008) Zc(4430) BaBar: PRD79, (2009) K+ large K* background J/ Belle: Charged charmonium like M = Fully Compatible = MeV Very close to D*D1 threshold MeV BaBar: Effect of highly excited K* states We obtain mass and width values that are compatible with theirs [ ] bur only 1.9 s; fixing the mass and with increased this to only

79 Zc(4430) quantum numbers arxiv: Vetoed regions 4 D dalitz plot fit M(k ), M(, elicity, K*(892) and K*(1200) are vetoed broader K* resonances are included in the fit Belle confirms again the Z(4430) with a slightly different mass (No more close to D*D1 threshold) 1+ is preferred 0 cannot be excluded 12

80 Updated ISR e+e- J/ PRL 110, (2013) Belle updated its 2007 analysis of ISR process e+e- J/ using the full data sample Y(4008) Y(4260) Y(4008) and Y(4260) are confirmed with higher statistic 13

81 Updated ISR e+e- J/ PRL 110, (2013) Y(4260) J/ and Y(4170) hc The dalitz plot seems incompatible with phase space model 13

82 Discovery of Zc(3895) Belle: 927 fb-1 of ISR data at ϒ(nS) energy BES-III: 525 Y(4260) peak energy PRL 110, (2013) PRL 110, (2013) A new charged charmonium like state very close to DD* threshold! Significance > 5.2 Significance > 8 Mass = (3894.5±6.6±4.5) MeV Mass = (3899.0±3.6±4.9) MeV Width = (63±24±26) MeV Fraction = (29.0±8.9)% (stat. only) Full Agreement Width = (46±10±20) MeV Fraction = (21.5±3.3±7.5)% 14

83 What is Zc(3895)? Theoretical models Tetraquarks arxiv: , arxiv , arxiv , arxiv: Molecules arxiv: , , Meson loop ArXiv: , arxiv: ISPE model arxiv: Is it really a new state? f0, and other S wave dipion contribution are present, but not peaking f2 and other P wave dipion contribution are almost absent No peaking background or interference mechanism have been identified 15

84 What is Zc(3895)? Theoretical models Tetraquarks arxiv: , arxiv , arxiv , arxiv: Molecules Is the Zc the charmonium couterpart arxiv: , , of the Zb? Meson loop ArXiv: , arxiv: Similar production mechanism ISPE model Similar location (DD* vs BB* threshold) arxiv: Zc decays? Zc quantum numbers? Is it really a new state? f0, and other S wave dipion contribution are present, but not peaking f2 and other P wave dipion contribution are almost absent No peaking background or interference mechanism have been identified 15

85 The Nagara event beam on emulsion target (Phys. Rev. Lett. 87, ) binding energy = 7 MeV M(H) > MeV (90% CL) 2M( ) = MeV

86 Missing Mass Missing mass as a too for simplify the analysis of complicate final states Y(4S) Missing mass MM MM 2=( Pμcm Pμreco ) ( Pμ cm Pμ reco ) Missing mass in CM frame 2 MM =m Measured or fixed 2 reco +s 2 s E reco Measured Known Resolution assuming negligible natural width of the products σ 2MM 2=4 ( E 2R + s) σ 2p p 2i i p σ +4 σ ( E 2 R p s R +s) mi2 + p i Tracking / Calorimetry resolution i Beam Energy resolution 14

87 Missing Mass Resolution p 2i σ MM 2=4 ( E R + s) σ p p R i mi + p i Beam energy resolution: 5 MeV Y(4S) width: 20 MeV Y(2S) width: 31 KeV σ p +4 σ s ( E R + s) i Beam Energy resolution 15

88 Missing Mass Resolution p 2i Negligible (or small) σ MM 2=4 ( E R + s) σ p p R i mi + p i σ p +4 σ s ( E R + s) i Beam Energy resolution Beam energy resolution: 5 MeV Y(4S) width: 20 MeV Y(2S) width: 31 KeV When running at narrow quarkonia σs ΓY (ns) 16

89 Missing Mass Resolution p 2i σ MM 2=4 ( E R + s) σ p p R i mi + p i σ p +4 σ s ( E R +s) i Tracking / Calorimetry resolution Try to use charged tracks but eff( ) >> eff( ) 17

90 Missing Mass Resolution σ 2MM 2=4 ( E 2R + s) σ 2p p 2i i p σ +4 σ ( E 2 R p s R + s) mi2 + p i i Tracking / Calorimetry resolution Try to use charged tracks but eff( ) >> eff( ) Use a kinematic fit to constrain t meson mass MC simulation of Y(4S) hb(1p) 18

91 Continuum Suppression Quarkonium annihiltions are usually spherical Y(nS), hb(np) ggg b(ns) gg us r T Axis based Thrust Major Thrust Minor Multipole Moments t trust =Max( i [ p i t ]) B n= i, j [ p i P n (cos(θi ))] e e+ is x ta Beam Axis 7

92 Continuum Suppression Quarkonium annihilti are usually spherical Y(nS), hb(np) ggg b(ns) gg Axis based Thrust Major Thrust Minor Multipole Moments (3x3) matrix with = x,y,z Linear combination of Self correlation based Spherici the eigenvalues ty Oblatne ss Fox Wolfram moments Planarit 8

93 Fox-Wolfram moments PRL (1978) Original problem: Discriminate 2 VS 3 jets events in e+e collision Evolution of the Multipole moments Angle between Beam axis other particles' i and j momenta Legendre polynomial order n M n = i, j pi p j P n (cos θij ) j and i particle momentum M 0= i, j pi p j =s Massless approx M 1= i, j pi p j cos θij M 2= 12 i, j pi p j (3 cos2 θij 1) H n=m n / s=m n / M 0 Best discrimination: H2 (a.k.a. R2) ggg qq qqg 9

94 Y(1,2S) ggg : the deuteron Protons and neutrons can interact and bound to form a deuteron

95 Deuteron at Belle de/dx [KeV/cm] de/dx value has strong cos( ) and p_lab dependence Exp GeV < p < 0.3 GeV Positive tracks cos( Experiment dependent NOT Lumi dependent NOT Ecm dependent Our explanation: CDC calibration is splitted in forward backward CDC calibration is exp dependent Optimized for pi/k tricky interplay with the saturation when we deal with highly ionizing tracks We need to calculate a data driven correction using the positive tracks.

96 Angular dependence 575 MeV< plab < 600 MeV Exp 11 Exp 65 Exp 51 Exp 71

97 Deuteron in Y(1S) dataset More detailed study of Y(1S) dataset Analysis restricted in this region de/dx [kev/cm] GeV < plab < GeV cos( _lab)

98 Deuteron in Y(1S) dataset dedx(deuteron) / dedx(proton) At given momentum, the ratio dedx(deuteron) / dedx(proton) should be flat in cos( _lab) mass dependet saturation effects tracking biases for deuteron? Y(1S) data, positive tracks MeV MeV MeV MeV cos( _lab)