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New BES and CLEO Results Weiguo Li Institute of High Energy Physics,

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  1. New BES and CLEO Results Weiguo Li Institute of High Energy Physics, Beijing 100049, P.R. China liwg@ihep.ac.cn ICHEP06, Moscow, July 31, 2006

  2. Outline • Introduction • Hadron Spectroscopy from J/ Decays • (2S) and CJ Physics • D/Ds physics and (3770) Decays • Future Plan • Summary Selected topics, thank CLEO and Hanna Mahlke_Kreuger for providing CLEO results

  3. BES and CLEOc are two Recent e+e- Experiments in the Energy Range 2 –5 GeV BESII (1997 - 2004) CLEOc (2003-now) 2-5 GeV R measurements 6+85 energy points (till 2000) Several points in 2004 J/ 5.8107 (2S) 1.4 107 (3770) ~27 pb-1 (2S) 3 106 (3770) 281 pb-1 4170 MeV ~200 pb-1 CLEOc detector has better performances than BESII

  4. Light Hadron Spectroscopy from J/ Decays • Scalars: ,  clearly observed • Possible pp bound state in J/  pp • X(1835) in J/  ’ • The  threshold enhancement in J/   • New observation of a broad 1- - resonance in J/  K+K- 0 Refer to BES talk by Shan Jin

  5. The  pole in at BESII 0 M(+-0)  M()  M(+-)  Averaged pole position: MeV Phys. Lett. B 598 (2004) 149

  6. κ Phys. Lett. B 633 (2006) 681

  7. Phys. Rev. Lett. 91, 022001 (2003) Observation of an anomalous enhancement near the threshold of mass spectrum at BES II J/ygpp BES II acceptance weighted BW +3 +5 -10 -25 M=1859 MeV/c2 G < 30 MeV/c2 (90% CL) c2/dof=56/56 0 0.1 0.2 0.3 3-body phase space M(pp)-2mp (GeV) acceptance

  8. This narrow threshold enhancement is NOT observed in J/pp at BESII • This indicates X(1860) has a production property similar to ’ meson. • This also indicates X(1860) may have strong coupling to gluons as ’ meson. Preliminary J/ pp No narrow strong enhancement near threshold

  9. Not seen in pp experiment • In pp experiments, its expected cross-section is much smaller than continuum process. • In pp elastic scattering, I=1 S-wave dominant, while in J/ radiative decays I=0 S-wave dominant. • Pure FSI disfavored not seen in: B+ K+ pp (BELLE) Y(1S) pp(CLEO)

  10. X(1835) 5.1  X(1835) 6.0  Observation of X(1835) in J/+- Phys. Rev. Lett., 95 (2005) 262001

  11. Combine two channels 7.7 Statistical Significance 7.7  X(1835) Phys. Rev. Lett., 95 (2005) 262001

  12. Re-fit to J/pp including FSI Include FSI curve from A.Sirbirtsev et al. ( Phys.Rev.D71:054010, 2005) in the fit (I=0) M = 1830.6  6.7 MeV  = < 153 MeV @90%C.L. In good agreement with X(1835)

  13. X(1860) and X(1835) might be the same state • masses and widths are consistent. • both connected with ’ meson.  Its spin-parity should be 0-+: this would be an important test. Excited ’ ? Glueball? pp bound state? A mixture of glueball and pp bound state?

  14. Observation of  thresholdenhancement in J/   K+K- +-0   M(K+K-)  Dalitz plot M(+-0) M(K+K-)   M2(g) M(+-0) M2(gw)

  15. A clear threshold enhancement is observed Phase Space Eff. curve Side-bands Side-bands do not have mass threshold enhancement!

  16. The decay of J/ is observed and an enhancement in  is found near the threshold. • PWA shows: the enhancement favors 0++ • Is it the same 0++ observed in KK or , or is it a • glueball, or a hybrid …..? • Further study in , K*K*,  …. desirable ! Phys. Rev. Lett., 96 (2006) 162002

  17. New observation of a broad 1-- resonance in J/  K+K- 0 K*(1410) 0 K*(892) 0 sideband background ? hep-ex/0606047

  18. What is the threshold bump? • JPC should be 1--, 3--, … (Parity conservation) • PWA results • Following components are neededK*(892), K*(1410), (1700), X • 1– is much better than 3— • Pole position of X is • Br • Big destructive interference among X, (1700) and PS Width ~ 800 MeV

  19. More Checks • Replace X by (770), (1900), (2150) with interference among each other, S = 85 not from the interference of known particles • Replace X by (1450) S = 36 ( 8.2)& Br((1450) K+K-) < 1.6  10-3 (95% C.L.)  not (1450) • Further look in to determine its isospin • Search for its K*K, KK decay modes

  20. Property of X(1580) • The width is much broder than other mesons, such as (1450), (1700) Could have different nature from conventional mesons. • The large width is the expectation for a multiquark state(Tetraquark interpretation: M. Karliner, H.J. Lipkin, hep-ph/0607093) hep-ex/0606047

  21. (2S) and CJ Physics Continuum contribution and phase in (2S) decays Branching ratios Phase Interference needs to be considered. Continuum contribution should be subtracted … The interference are neglected in many of the current analyses.

  22. With BESII 14 M (2S) events and 6.4 pb-1 (s=3.65 GeV) and CLEOc 3 M events and 21 pb-1(s=3.67 GeV)12% rule are tested for different modes and the phases between three glue and one photon processes for some modes are measured.

  23. The universal -90°phase? |φ| J/ψ Decays: 1. AP: 90°M. Suzuki, PRD63, 054021 (2001) 2. VP: (106 ±10)°J. Jousset et al., PRD41, 1389 (1990) D. Coffman et al., PRD38, 2695 (1988) N. N. Achasov, talk at Hadron2001 3. PP: (90 ±10)°M. Suzuki, PRD60, 051501 (1999) (103±7)°BES, PRD69, 012003 (2004) 4. VV: (138 ±37)°L. Köpke and N. Wermes, Phys. Rep. 174, 67 (1989) 5. NN: (89 ±15)°R. Baldini et al., PLB444, 111 (1998) ψ(2S) Decays: 1. VP: φ=180°(± 90 ° ruled out!)M. Suzuki, PRD63, 054021 (2001) φ=180° or φ=-90°P. Wang et al., PRD69, 057502 (2004) 2. PP: (-82±29)°or(121±27)° BES, PRL92, 052001 (2004) & Yuan, Wang, Mo, PLB567, 73 (2003) More modes and more (ψ(2S) and continium data are needed

  24. “12% rule”and“ puzzle” M. Appelquist and H. D. Politzer, PRL34, 43 (1975) • Violation found by Mark-II , confirmed by BESI at higher sensitivity. • Extensively studied by BESII/CLEOc • VP mode:  , K*+K-+c.c., K*0K0+c.c., 0,… • PP mode: KSKL, K+K-, +- • BB mode: pp, , … • VT mode: K*K*2, f2’, a2, f2 • 3-body: pp0, pp, +-0, … • Multi-body: KSKShh, +-0 K+K- , 3(+-), …

  25. ’ + - 0 BESII: PLB619, 247 (2005) CLEOc: PRL94, 012005 (2005) 2290s 1960s BESII CLEOc BES and CLEOc in good agreement!

  26. ’ + - 0 Dalitz plots after applying 0 mass cut! Very different from J/3! CLEOc BESII J/ Similar Dalitz plots, different data handling. PWA vs counting! ’ is observed, it is not completely missing, BR is at 10-5 level!

  27. J/, ’ VP BESII : PLB614, 37 (2005); PRD73, 052007 (2006) CLEOc : PRL94, 012005 (2005)

  28. Summary of “12%” rule, Seems no obvious rule to categorize the suppressed, the enhanced, and the normal decay modes of J/ and ’. The models developed for interpreting specific mode may hard to find solution for other (all) modes. • ’ VP suppressed • ’ PP enhanced • ’ VT suppressed • ’ BB obey/enh • Multi-body obey/sup Similarly ’’ decays have a rule of 0.02%, more data and more sophisticated analysis needed to extract the branching fractions from the observed cross sections. Here because the time limitation, I will omit here. • Model to explain J/, ’ and ’’ decays naturally and simultaneously? • S-D mixing in ’ and ’’[J. L. Rosner, PRD64, 094002 (2001)] • DD-bar reannihilation in ’’(J. L. Rosner, hep-ph/0405196) • Four-quark component in ’’[M. Voloshin, PRD71, 114003 (2005)] • Survival cc-bar in ’(P. Artoisenet et al., PLB628, 211 (2005)) • Other model(s)?

  29. cJ production at BESII and CLEO-c CLEO: Phys.Rev. D70 (2004) 112002 • ψ(2S)→cJ, J=0,1,2 - BJ~9%,“cJ factory” - observed in inclusive analysis - B(cJ→hadrons)are not well known c1 c0 c2 • Selected analyses of cJ hadronic decays: • -cJ →η(’)η(’) • -cJ → VV (V = φ, ω) • -cJ → h+h−h0,3-body • decays BES preliminary CLEO preliminary CLEO-CONF-06-9 Refer to BES talk by Ronggang Ping and CLEO talk by Tomasz Skwarnicki

  30. ccJh(’) h(’) cc2 CLEO preliminary cc0 cc1 spin-parity forbiddenResolution 4-8MeVe including intermed BR 4-6% cc1 B(c0) = 0.31 ± 0.05 ± 0.04 % B(c0//) = 0.18 ± 0.04 % ± 0.03 % B(c0/) < 0.05% (90% CL) B(c2) < 0.05% (90% CL) B(c2 //) < 0.03% (90% CL) B(c2/) < 0.023% (90% CL) Comparison with theory: r: DOZI/SOZI • CLEO 2006 preliminaryBES PRD67:032004,2003E835 PRD72:112002, 2005 ▼ ▪ source:Qiang Zhao, PRD72:074001, 2005

  31. BES: cJ→2(K+K) hep-ex/0607025 cJ Pair production of vectors c0 c1 c2 Improved precision over PDG (BESI) results on cJKKKK and . First measurement of cJKK.

  32. Pair production of vectors cJ 38 c0 28 c2 First observation: B(c0) = (2.290.580.41)10-3 B(c2) = (1.770.470.36)10-3 BES: PLB630, 7 (2005)

  33. BES preliminary CLEO preliminary hep-ex/0607072 B (cJ→ h0h+h−) CLEO preliminary (%) 2 Notice: different units 1/2 BES preliminary BES: PRD74, 012004 (2006) BES and CLEO in good agreement!

  34. D, Ds Decay Measurements • Hadronic • Semi-leptonic Form factor • Leptonic fD, fDs mostly from CLEO p/p: 0.6% @ 1GeV E/E: 2.2% @ 1 GeV 5% @ 100 MeV PID(/K):  > 90% mis < 5%

  35. (Similar comments apply for DS) “D Tagging”(AKA “The MarkIII Method”) + e Basic Strategy (most CLEO-c analyses): • Full reconstruction of one D meson decay into hadrons (“Tag D”) • Search remainder of event for signal D decayhadronic or (semi-)leptonic e.g. B(D+ K-++) = #(K-++) in tagged events ( (K-++) * #tags ) • Tag efficiency ~20% D+, 30% D0 K+K-p+ Single tags are clean Compute m(D)rec with ED=Ebeam and pD from reconstructed decay products; resolution improves greatly Continuum,  pair, radiative return events suppressed significantly. m(D cand)rec (GeV)

  36. Expected #ST: Expected #DT: Since eij  ei ej, correlated systematics cancel in NDD To first order, Bi is independent of tag modes’ efficiencies, s,L. D Hadronic BF (Cabibbo-Favored) Use 3 D0 and 6 D+ modes - Count #Single Tags (ST): Niobs(9) - Count # Double tags (DT): Nijobs (45) Double Tagged, 281 pb-1 • Update from 56 pb-1 to 281 pb-1 soon • Some systematics still being studied. • O(1%) stat & syst errors on golden modes in sight… 56pb-1 CLEO PRL 95, 121801 (2005) Refer to CLEO talks by Steven Blusk

  37. p+p0 p+p+p- p+p0p0 p+p+p-p0 p+p+p+p-p- K-p+p+ p+p-p0 p+p- p0p0 p+p- p+p- p+p- p0p0 p+p- p+p-p0 D Hadronic BF (Cabibbo-Suppressed) • First observations… untagged  281pb-1  CLEO PRL 96, 081802 (2006) • Isospin Analysisof pp final state • A2/A0 = • 0.420±0.014 ±0.010 • Strong phase shift: • = (86.4±2.8±3.3)0 Large FSI in D decays.   Other first/improved BF’s D0hp0, wp+p-, D+hp+

  38. Measurement of D KL0 CLEO preliminaryhep-ex/0607068 Reconstruct entire event, except for Kl0, and plot missing mass squared:Mmiss2=(pD-pp)2 (6 tag modes) ~2000 signal events • Expect due to interferencebetween and . 281 pb-1 data ~1100 signal events (3 tag modes)

  39. DKL0p Results and the Strong Phase CLEO preliminaryhep-ex/0607068 uncertainty due B(DKS0) First measurements! not including p0 systematic • Results: • B(D0KL0p0) = (0.940 ± 0.046 ± 0.032)% • B(D+KL0p+) = (1.460 ± 0.040 ± 0.035 ± 0.009)% • Also measure B(D0Ks0p0) = (1.202 ± 0.016 ± 0.039)% • Asymmetries: • R(D0) = 0.122 ± 0.024 ± 0.030 • R(D+) = 0.030 ± 0.023 ± 0.025 Expected Asymmetries Isospin decomposition of D to K pi amplitudes: 6 parameters, 7 measurements

  40. acc by PRDCLEO-Conf-06-15 D0K+K-p0 Dalitz Analysis Similar fitting technique to Dp+p-p+ analysis Key inputs to g ~9 fb-1 on/just below(4S) Reconstruct D*+D0p+, D*-D0p- pcharge tags the D0 flavor at prodn K*- 735 candidates f K*+ K*+ Read off the values from the DP fit rD= 0.52±0.05±0.04 dD = (332±8±11)o • First measurement of dD. • Significant improvement on rDover previous value using K*K BF’s

  41. Ecm=4160 MeV Simulations < DE > = 0 DsDs* DD DsDs DD* D*D* CLEO preliminary • Scan the region 3970-4260 MeV • Optimize Ds physics • Study D(s) XS in this region • Confirm Y(4260) The Ds Scan • No need to reconstruct D*, as Mbc differentiates event types. • For DD and DsDs cut on E and use Mbc to extract yields. • For other event types cut on Mbc and use invariant mass to extract yield. • 12 scan points • ~60 pb-1 (total) • Ecm=4170 selected • Additional 180 pb-1collected at 4170 MeV

  42. Ds+, Ds-combined Exclusive DsHadronic Decays • Follows very similar procedure as for y(3770)DD • Kinematic variables: cut on Mbc, fit in M(Ds) • Look at 6 modes: KsK+, K+K-p+, K+K-p+p0, p+p-p+,hp+,hp+ • Single tag yields ~0.4-4k, double tag yields up to ~100 KKp single tag events, signal fit in each m(KK) bin Yield Br(Ds-K+k-p- )= (5.57 ±20 ±20 )% CLEO determines partial branching fraction: m(K+K-) within m(f)±10 MeV: 1.98±0.12±0.09% (~x2+O(10%)) K+K- mass m(f) CLEO preliminaryhep-ex/0607079 Better to use K+K-+ as normalizing mode

  43. K- K+ - e+ Semileptonic Reconstruction at (3770) 281pb-1: ~310k D+, ~160k D0 tags Semileptonic decays are reconstructed with no kinematic ambiguity Signal events: U = Emiss– |Pmiss| = 0 ~7000 events (log version with tails later) U = Emiss– |Pmiss| (GeV) Tagging creates a single D beam of known 4-momentum Refer to CLEO talk by Yongsheng Gao

  44. 69928 679684 29520 291055 U = Emiss– |Pmiss| (GeV) D  p/KenBranching Fractions & Form Factors With 281/pb D tagging 134749 14397132 45029 584688 Emiss and Pmiss are missing energy and momentum of the event Plots Integrated over all q2

  45. D ,Ken Branching Fractions Comparison D → K e+ ν D → π e+ ν Good consistency between measurements. LQCD precision lags experiment.

  46. Form Factors as a Stringent Test of LQCD Shape α LQCD LQCD C. Aubin et al., PRL 94 011601 (2005). DATA FIT CLEO preliminary LQCD DATA FIT Vcd = 0.22380.0029 LQCD lags exp. Vcs = 0.97450.0008(CKM unitarity)

  47. Vcs and Vcd Results CLEO preliminary Combine |Vcx|f+(0)valuesfrom fits with unquenched LQCD results forf+(0) (Phys. Rev. Lett. 94, 011601 (2005)) to extract |Vcs| and |Vcd|. Tagged and untagged consistent. 40% of events are common to both analyses: DO NOT AVERAGE!Uncertainties: experiment: Vcs <2%, Vcd~4% / LQCD: 10% Vcs (Wcs LEP) and Vcd (vN) well measured  good agreement between PDG(HF) and CLEO-c results primarily a check of the LQCD value for f+(0). Nevertheless, the most precise & robust Vcs & Vcd determinations using semileptonic decays to date.

  48. CLEO preliminary 32.7  6.7 Rare semileptonicD decays D0K-p+p-e+ne 8.5 +4.5-3.2 ICHEP conf paper D+we+n 13.3  4.0 37.3  6.7 * First observation ** Improved UL (factor 100) *** Error halved D tagged, 281pb-1

  49. Simultaneous fit to D+ 0e , D0 -e Rv = 1.40  0.25  0.03 R2 = 0.57  0.18  0.06 D tagged, 281pb-1 Dren (BR+FF) cos  Interest: 1st measurement of FF in Cabibbo suppressed charm PS V decay q2 Need DK*en and Dren FF Grinstein & Pirjol [hep-ph/0404250] D+ 56pb-1 281pb-1 cos e  Line is projection for fitted RV, R2 Fixed background shape and signal tails from MC 56pb-1 D0 B(D0 -e+)= (1.560.160.09)10-3 B(D+ 0e+)= (2.320.200.12) 10-3 Isospin average: G(D0  r-e+n) = (0.410.030.02)10-2 ps-1 281pb-1 CLEO preliminary

  50. Inclusive Semileptonic Results Consistent with the known exclusive modes saturating the inclusive branching fractions . Extrapolated below 0.2 CLEO-c 281pb-1, D Tagged hep-ex/0604044, subm to PRL Consistent with isospin symmetry