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Charmonium Decays in CLEO Tomasz Skwarnicki Syracuse University I will concentrate on the recent results. Separate talk covering Y(4260).
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Charmonium in CLEO ICHEP'06 Moscow Tomasz Skwarnicki2 CLEO-c Data Samples By far the largest (3770) sample The (2S) sample not the largest, but still unique because of the CLEO detector capabilities (excellent tracking, EM calorimeter and PID) 5.6pb -1, 3M (2S) 20.7pb -1 continuum below (2S) 281pb -1, 1.8M (3770) 60pb -1, scan 3.97-4.26 GeV 200pb -1 at 4.17 GeV Ian Shipsey’s talk on Y(4260) J/ (1S) R E(e + e - ) GeV
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Charmonium in CLEO ICHEP'06 Moscow Tomasz Skwarnicki3 Photon transitions: (3770) cJ –Is (3770) a regular cc state? –Effects due to 1 3 D 1 - 2 3 S 1 mixing? –Reliability of the predictions for states above the open charm threshold? Two complementary methods: – cJ J/ J/ e e Excellent background suppression but poor sensitivity to c0 – cJ K K K K More backgrounds but good sensitivity to c0 –Total energy-momentum constraints suppress the backgrounds and improve the photon energy resolution (2S) cJ as control sample cc n 2S+1 L J S= 0 1 0 1 0 1 L= 0 1 2 n=1 n=2 l+ll+l (2S) (3770) cJ J/ 2K,2K2 ,4 ,6 Rare because 10 0 -10 2 keV while (3770) DD =25 MeV Interesting because of well grounded potential model predictions for (1 3 D 1 ) 1 3 P J
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Charmonium in CLEO ICHEP'06 Moscow Tomasz Skwarnicki4 Photon transitions: (3770) cJ hadrons PRL 96 182002 (06) hep-ex/0605070 hadrons CLEO-CONF-06-6 signal (2S) bkg other bkg c0
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Charmonium in CLEO ICHEP'06 Moscow Tomasz Skwarnicki5 Photon transitions: (3770) cJ Dominant J-dependence (3770) photon transition rates fit the pattern expected for the 1 3 D 1 cc state In non-relativistic limit no J-dependence of the E1 matrix element signature of the 1 3 D 1 state
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Charmonium in CLEO ICHEP'06 Moscow Tomasz Skwarnicki6 2 3 S 1 – 1 3 D 1 Mixing ? No consistent solution can be obtained in the non-relativistic approach Mixing angle is small Theoretical curves from the non-relativistic calculations by J. Rosner hep-ph/0411003 (2S) (3770) CLEO-c results
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Charmonium in CLEO ICHEP'06 Moscow Tomasz Skwarnicki7 Importance of relativistic corrections Non-relativistic calculations overestimate photon transition rates for the charmonium Qualitatively, potential model predictions work for the 1 3 D 1 state equally well as for the 2 3 S 1 state ( GeV -1 ) Based on CLEO-c results (J-averaged) Non-relativistic Relativistic Rosner hep-ph/0411003 Ding,Qin,Chao PRD44,3562(91) Eichten,Lane,Quigg PRD69,094019(04) Barnes,Godfrey,Swanson PRD72,054026(05)
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Charmonium in CLEO ICHEP'06 Moscow Tomasz Skwarnicki8 non-DD decays of (3770) No evidence for anomalously large non-DD component CLEOBR [%] c0 0.73 0.07 0.06 c1 0.29 0.05 0.04 c2 <0.09 + - J/ 0.19 0.02 0.02 0 0 J/ 0.08 0.02 0.02 J/ 0.09 0.03 0.02 0 J/ <0.03 0.03 0.01 K0SK0LK0SK0L <0.001 Detected so far 1.41 0.10 0.16 missing event energy (GeV) after finding +, -, J/ ( ll) e + e - (2S) (J/ + - ) (3770) J/ + - CLEO PRL,96,082004 (06) CLEO PRD,73,012002 (06) (many upper limits presented in this paper too) CLEO PRL,95,121801 (05) CLEO PRL,96,092002 (06) vs. CLEO hep/ex-0603026 CLEO-CONF-06-7 vs. (9 ± 2 ± 6)% BES-II Gang Rong’s talk
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Charmonium in CLEO ICHEP'06 Moscow Tomasz Skwarnicki9 Results relevant for the interpretation of X(3872) Combining results from the previous slides: –X(3872) cannot be 1 3 D 2 cc state! –A moot point by now, since Belle, CDF, BaBar have shown X(3872) is J PC =1 ++
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Charmonium in CLEO ICHEP'06 Moscow Tomasz Skwarnicki10 M(K s ) GeV D0D0 Results relevant for the interpretation of X(3872) D0 mass: – (3770) D 0 D 0 Very small background D 0, K s, have small momenta –D 0 mass scale well calibrated via K s, masses –1864.85±0.15±0.20 MeV CLEO PRELIMINARY –1864.5±0.40 MeV PDG’06 fit –1864.1±1.00 MeV PDG’06 average M X(3872) M D 0 D 0* = M X(3872) (2M D 0 + M D 0* D 0 )= – 0.1±1.0 MeV PDG’06 – 0.4±0.7 MeV PDG’06+CLEO The error is now limited by the X(3872) mass measurement Accidental mass coincidence even less likely. D 0 D 0 * molecule, other 4-quark state with small binding energy, or a threshold cusp? tag K s ( )(K K )
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Charmonium in CLEO ICHEP'06 Moscow Tomasz Skwarnicki11 (2S) as cJ factory e + e − → (2S) –5pb -1, CLEO III+c, 3M (2S) –by the end of the year ×10 (2S)→ cJ, J=0,1,2 –B~9% each J, “ cJ factory” –observed in inclusive analysis –B( cJ →hadrons ) are not well known Selected analyses of cJ hadronic decays: –Channels involving neutrals: cJ → η ( ’ ) η ( ’ ) cJ → h + h − h 0, 3-body decays, Dalitz plot analysis c0 c1 c2 CLEO PRD,70, 112002 (2004)
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Charmonium in CLEO ICHEP'06 Moscow Tomasz Skwarnicki12 cJ ( ’ ) ( ’ ) B( c0 ) = 0.31 ± 0.05 ± 0.04 % B( c0 / / ) = 0.18 ± 0.04 ± 0.02 % B( c0 / ) < 0.05% (90% CL) B( c2 ) < 0.05% (90% CL) B( c2 / / ) < 0.03% (90% CL) B( c2 / ) < 0.023% (90% CL) Theoretical model by: Qiang Zhao, PRD,72,074001(05) r = Double-OZI/Single-OZI c1 spin-parity forbidden c2 c0 c1 CLEO preliminary BES E835 Fits all
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Charmonium in CLEO ICHEP'06 Moscow Tomasz Skwarnicki13 Analysis of cJ →h 0 h + h − See results on the next slide c2 c0 c1 c2 c0 c1 c2 c0 c1 c2 c0 c1 pp KK KK KK ’ pp Kp
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Charmonium in CLEO ICHEP'06 Moscow Tomasz Skwarnicki14 Most of them are the first observations! Statistics in c1 → + −, K + K − 0, K 0 s K sufficient for Dalitz plot analysis of resonant substructure (following slides) Analysis of cJ →h 0 h + h − CLEO PRELIMINARY (upper limits at 90% C.L.) CLEO-CONF-06-9 (in %)
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Charmonium in CLEO ICHEP'06 Moscow Tomasz Skwarnicki15 Dalitz plot analysis of c1 → + − May offer the best way to determine a 0 (980) parameters in the future 10x increase in statistics expected this year CLEO PRELIMINARY a 0 (980) f 2 (1270)
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Charmonium in CLEO ICHEP'06 Moscow Tomasz Skwarnicki16 Dalitz plot analysis of c1 → K + K − 0 Analyzed together with K 0 s K see the next slide for the fit results K*(892) a 0 (980) K*(1430)
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Charmonium in CLEO ICHEP'06 Moscow Tomasz Skwarnicki17 Dalitz plot analysis of c1 → K 0 s K K*(892)K,a 0 (980) clearly seen Need more data to sort out other contributions KK fit results CLEO PRELIMINARY Model dependent K*(892) a 0 (980) K*(1430)
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Charmonium in CLEO ICHEP'06 Moscow Tomasz Skwarnicki18 Search for (2S) → c (1S) B( (2S) → c ) < 0.1% (90% C.L.) Rules out “survival before annihilation” model by P.Artoisenet et al. PLB,628,211 (05) invented to explain the “ puzzle” (predicted B > 1%) MC data cc c → K + K 0, + K + K K + K , + + , K 0 K + CLEO CLNS 06/1965 CLEO PRELIMINARY
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Charmonium in CLEO ICHEP'06 Moscow Tomasz Skwarnicki19 Analysis of (2S) → 2 pseudo-scalars Confirm BES results The phase difference between the EM and strong amplitudes around 90 o, which is consistent with the J/ value, contrary to some theoretical speculations that it might be very different CLEO hep-ex/0603020 CLEO-CONF-06-8
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Charmonium in CLEO ICHEP'06 Moscow Tomasz Skwarnicki20 Summary Potential models predict for (3770) cJ equally well as for (2S) cJ No evidence for anomalously high (3770) non-DD (3770) appears to be standard 1 3 D 1 cc state with a small admixture of 2 3 S 1 Preliminary precision measurement of D 0 mass improves M X(3872) M D 0 D 0* determination to 0.4±0.7 MeV Vast improvement in measurements of exclusive hadronic decay modes of the cJ states. An order of magnitude increase in (2S) statistics (x10) expected soon. Significant improvement in (3770) statistics (x3) expected by 2008.
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