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Recent CLEO results on hadron spectroscopy

Recent CLEO results on hadron spectroscopy. Tomasz Skwarnicki Syracuse University. Concentrate on the most recent results (mostly quarkonium spectroscopy). Production of b-quark hadrons. G ¡( 3S ) ~ 24 keV. c. G ¡( 4S ) ~ 24 000 keV. W. q. g. p. p. e +. e +. b. B ( s ) (*). b.

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Recent CLEO results on hadron spectroscopy

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  1. Recent CLEO results on hadron spectroscopy Tomasz Skwarnicki Syracuse University Concentrate on the most recent results (mostly quarkonium spectroscopy).

  2. Epiphany 2005, Krakow Tomasz Skwarnicki Production of b-quark hadrons G¡(3S) ~ 24 keV c G¡(4S) ~ 24 000 keV W q g p p e+ e+ b B(s)(*) b Soft g g g Other states ¡(4S,5S) ¡(1S,2S,3S) B(s)(*) Hard g b b e- e- Short distance interactions Long distance interactions bb spectroscopy bq, (cq, cc) spectroscopy

  3. Epiphany 2005, Krakow Tomasz Skwarnicki fb-1 /year Belle 100 • Long runs at ¡(5S)¡(3S), ¡(2S),¡(1S) in 2001 – 2002. BaBar 10 • CLEO-c phase 2003 – (2007) 1 CLEO-c ¡(3S) 0.1 ¡(2S) ¡(1S) 0.01 0.001 3 History of CLEO/CESR • B physics runs (¡(4S)) at CLEO ended in mid 2001. or # of resonances ¡(5S) ¡(3S) ¡(2S) ¡(1S)

  4. Epiphany 2005, Krakow Tomasz Skwarnicki CLEO-III data samples (in millions of resonance decays) • CLEO “owns” the field of ¡spectroscopy • Recently more than 10-fold increase in statistics for the narrow ¡resonances over the previous generation of experiments ¡(1S) ¡(2S) ¡(3S) (in integrated luminosity fb-1) ¡(5S) ¡(4S) Continuum below ¡(4S) • Except for a few systematics limited measurements CLEO is no longer competitive in B physics • Large increase in statistics for ¡(5S) with much improved detector leads to a measurement of Bs production rate

  5. Epiphany 2005, Krakow Tomasz Skwarnicki CESR (single ring machine) PEP-II (double ring machine) CESR-c CESR(-b) Wigglers needed for low energy operations to increase radiation damping (to keep the size of the beams small) Superconducting CESR-c wiggler magnet (2.1 T)

  6. Epiphany 2005, Krakow Tomasz Skwarnicki CLEO-c data samples • Proposed CLEO-c program: • 3 / 3 / 1 fb-1 at Ebeam=3770 / 4140 / 3100 MeV for DD / DsDs/ J/y • Would also like to take some y(2S), Lc data and perform scan of R • Likely to be revised if CESR-c doesn’t reach its projected luminosity soon • Advantages of threshold production ofD(s)mesons: • Fully reconstruct one D(s) meson, then look at the other • No backgrounds (often limiting factor for D studies at B factories and fixed target experiments) • Measurement of absolute branching fractions ~6 pb-1 ~107 pb-1 We are continuing to run at y(3770) 3800 3720 3760 3640 3840 3680

  7. Epiphany 2005, Krakow Tomasz Skwarnicki CLEO-c data samples (in millions of resonance decays) y(3770) y(2S) • y(2S) sample smaller (larger) than that of BES (Crystal Ball) with much better detector • y(3770) sample much larger than those of Mark III and BES with much better detector

  8. Epiphany 2005, Krakow Tomasz Skwarnicki CLEO EM Calorimeter COIL (1.5T) • Essential for photon spectroscopy • ~8000 CsI(Tl) crystals + photo-diodes • First crystal calorimeter in magnetic field • In operation since 1990 (CLEO II) Much better g efficiency in hadronicevents Narrower p0 width

  9. Epiphany 2005, Krakow Tomasz Skwarnicki CLEO III Tracking • Large drift chamber in 1.5T field (lowered to 1.0T for CLEO-c) CLEO III DR Deconstruction of CLEO II DR Stepped endplate to accommodate new micro-b quadrupoles

  10. Epiphany 2005, Krakow Tomasz Skwarnicki CLEO-c Inner Wire Chamber • CLEO-III Silicon Vertex Detector deteriorated due to radiation damage and had to be replaced • “ZD Inner Chamber” commissioned Aug/Sep 2003 • The only new detector component of CLEO-c Tracking resolution • Much improved momentum and dE/dX resolution compared to the previous charm-threshold experiments 6 stereo layers 53 to 105 mm radius

  11. Epiphany 2005, Krakow Tomasz Skwarnicki CLEO-III RICH • LiF – MWPC (Methane + TEA) proximity focused RICH In operation since 2000 Kaon efficiency = 0.80 = 0.85 = 0.90 B physics CLEO-c Photodetectors MWPC (Methane+TEA) Radiators LiF First detector operating at charm threshold with excellent particle ID

  12. Epiphany 2005, Krakow Tomasz Skwarnicki Measurement of fD Calculate Missing-Mass to separate signal (MM=mn=0) from backgrounds:

  13. Epiphany 2005, Krakow Tomasz Skwarnicki Measurement of fD hep-ex/0411050 Accepted by PRD Based on 6 wiggler data: 60 pb-1 (29k tagged events) B(D- n p-) = (3.5±1.4±0.6) 10-4 D- KL p- fD- = (202±41±17) MeV D- n p- 8 events (1 background event expected) First statistically compelling evidence for this decay. (BES 2.7±1.7 eventshep-ph/0400150) Need much larger statistics to constrain the theory (data taking in progress!) The same type of calculations used for fB needed for extraction of Vtd from B0B0 mixing

  14. Epiphany 2005, Krakow Tomasz Skwarnicki D meson BRs Using double-tag method (Preliminary) PDG 2004 0.0380±0.0009 0.130±0.008 0.075±0.003 0.092±0.006 0.0141±0.0008 No surprises Future goal: reduce errors to 1-2% for the major modes

  15. Epiphany 2005, Krakow Tomasz Skwarnicki bb cc Heavy Quarkonia n2S+1LJ ¡’IV1981 n=4 ¡’’’1979 cb’1982 Belle, BaBar, CLEO n=3 ¡22002 y’’1974 ¡’’1977 y’’’1977 cb1983 CLEO-III cc1975 n=2 hc’’ 1982 n=2 Fine splitting: Fine splitting hc 1986 1992 ? 2002 E835 CLEO-c 2004 ¡1977 J/y1974 n=1 n=1 Hyperfine splitting: Hyperfine splitting hc1980 S= 0 1 0 1 0 1 0 1 L= 0 1 2 3 S= 0 1 0 1 0 1 L= 0 1 2

  16. Epiphany 2005, Krakow Tomasz Skwarnicki Tensor Spin-orbit J = L + 1 Spin-spin J = L J = L J = L - 1 Fine and Hyperfine Structure Hyperfine structure Fine structure • nS states are special: • Have no fine structure (L=0 thus J=S) • The only states for which hyperfine structure is predicted to be significant • Observed in charmonium: • M(J/y) – M(hc)= (116±2) MeV; M(y’) – M(hc’)= (48±4) MeV • If long range spin-spin forces are negligible then for L>0: • MS=0 = M(c.o.g.) = SJ (2J+1) MJS=1 / SJ (2J+1) • M(hc)=(5 M(cc2)+3 M(cc1) + M(cc0)) / 9 = (3525.3±0.1) MeV ??? S = 0 S = 1 n, L c.o.g

  17. Epiphany 2005, Krakow Tomasz Skwarnicki Inclusive search for hc y’ p0 hc hc g 156 ± 48 events 3.3s significant hc anything • Require p0 g recoil mass to be consistent with the hc mass • Plot p0 recoil mass (should reflect the hc mass)

  18. Epiphany 2005, Krakow Tomasz Skwarnicki Optimize hcreconstruction on y’ g hc hc g (M1) Signal sample y’ p0 hc  p0g hc hc 15.0 ± 4.2 events 5s significant hc mass sidebands Data MC Exclusive search for hc y’ p0 hc g (E1) hc KsKp,2Kp0,2K2p, 4p,2ph • Reconstruct hc in one of the exclusive decay modes • Then follow the same steps as in the inclusive analysis

  19. Epiphany 2005, Krakow Tomasz Skwarnicki • For comparison:hep-ex/040085 • Preliminary E835 results: • Disapprove E760 evidence for pp  hcp0J/y • ~13 pp ghcggg events in the peak • ~3.3s significance for hc • M(hc) =3525.8±0.2±0.2 MeV E835 Preliminary CLEO results for hc mass • Inclusive analysis: M(hc)= (3524.8±0.7) MeV • Exclusive analysis: M(hc)= (3524.4±0.9) MeV • Together: • M(hc)= ( 3524.7 ± 0.6 ± 1.0 ) MeV • M(cccog) - M(hc) = ( 0.6 ±1.2 ) MeV • Consistent with zero • In any case small as expected • The analysis is still in progress and numbers will change slightly before they are published

  20. Epiphany 2005, Krakow Tomasz Skwarnicki Search for X(3872) in gg fusion and ISR • Reconstruct exclusive p+p-J/y, J/yl+l- events in CLEO-III high energy data (15 fb-1) Untagged gg fusion JPC=0±+,2±+,… No signal found Initial State Radiation JPC=1_ _ • hep-ex/0410038 • Accepted by PRL

  21. Epiphany 2005, Krakow Tomasz Skwarnicki Search for X(3872) in gg fusion and ISR Assuming B(B± → K± X) ≈ B(B± → K± ψ’) → B(X → π+ π- J/ψ) ≈ 0.02 our limits imply: (2J+1)Ggg(X(3872)) < 0.65 keV • ¼ that for χc0 and χc2 • Ackleh &Barnes prediction • for 11D2 state: • (2J+1)Ggg(11D2) = 0.1 keV Gee(X(3872)) < 0.42 keV • comparable to ψ(3770) • ½ that of ψ(4040)

  22. Epiphany 2005, Krakow Tomasz Skwarnicki Determination of B(¡(nS) m+m-) • Much larger samples than previously available • Much better detector than previously available (tracking, calorimeter, muon system) Measure m+m-yields on and off the resonance peaks

  23. Epiphany 2005, Krakow Tomasz Skwarnicki Determination of B(¡(nS) m+m-) CLEO-III • Compared to the previous measurements: • Good agreement for ¡(1S) • Substantial disagreement for ¡(2S), ¡(3S) hep-ex/0409027 Accepted by PRL

  24. Epiphany 2005, Krakow Tomasz Skwarnicki Determination of Gtot(¡(nS)) B(¡(nS) m+m-) are important for determination of Gtot(¡(nS)) and CLEO-III values for Bmm and PDG values for Bmm • Important change for many comparisons of data (Bx) vs theory (Gx): Bx=Gx/Gtot

  25. Epiphany 2005, Krakow Tomasz Skwarnicki Photon transitions – E1 • Electric Dipole Transitions bb 7 8 y(2S) 9 BRg * GtotGE1 Eg M(n3PJ) J=2 1 0 16,17 18 10 1 11 cc 2 3 12 13,14,15 6 1 2 5,4 3 g g g J=2 1 0 4 g g 5 6 (3S) (2S) 2 1 8 3 7 9 12 11,10 16,17 18 g g g 6 5,4 6 5,4 Hadrons (…p0..) 15 14,13 g g

  26. Epiphany 2005, Krakow Tomasz Skwarnicki 16,17 18 (3S) 16,17 33S1 13P0 18 Photon transitions – E1 bb y(2S) (3S) 7 8 9 J=2 1 0 cc 3 2 8 7 1 9 1 2 3 J=2 1 0 (2S) 2 1 hep-ex/0408133 Accepted by PRD hep-ex/0408133 Accepted by PRL 3

  27. Epiphany 2005, Krakow Tomasz Skwarnicki Comparison to previous measurements - examples (3S)   bJ(2P2) (2S)   bJ(1P2) Improved precision Good agreement on Eg (i.e.m(cbJ) ) Disagreements on B((3S)   bJ(2PJ))

  28. Epiphany 2005, Krakow Tomasz Skwarnicki Fine splitting of P-states • Tests of relativistic corrections to the mass spectrum (=0.8 for pure Coulomb potential) Nearly equal, against most of theoretical predictions. bb cc The results favor confining potential of effective scalar type

  29. Epiphany 2005, Krakow Tomasz Skwarnicki Relativistic effects in transition rates • In non-relativistic approximation E1 matrix elements are spin (J) independent Ratio of Consistent with the NR expectations bb Relativistic effects in J=0 are expected to be the largest Smaller c-quark mass and substantial 2S-1D1 mixing cc

  30. Epiphany 2005, Krakow Tomasz Skwarnicki S.Godfrey 33S1 13PJ + - 23S1 13PJ 33S1 23PJ E1 matrix elements “Spin averaged” matrix elements • Large relativistic corrections (triangles) needed to describe E1 rates in charmonium. • Corrections small in bottomonium. • Small matrix element 33S1 13PJ difficult to predict (cancellations) 23S1 13PJ McClary 83 cc Grotch 84 23S1 13PJ bb 33S1 23PJ Date of publication 33S1 13P0 bb <1P0|r|3S>

  31. Epiphany 2005, Krakow Tomasz Skwarnicki Photon transitions – M1 • Magnetic Dipole Transitions bb y(2S) 3 6 5 cc 2 4 2 (3S) 4 3 (2S) 5 2 6 1 4 g g A way to reach singlet states Crystal Ball claimed observation of all M1 transitions in charmonium ~20 years ago (Direct: “1”, “2”,Hindered: “4”)

  32. Epiphany 2005, Krakow Tomasz Skwarnicki Search for hb(11S0) bb (4) M1 23S1ag11S0 y(2S) E1 6 cc Hindered M1 g E1 g 4 E1 23PJag13S1 (6) M1 33S1ag11S0 (3S) • No signal found for this or any other M1 transition in the Upsilon system

  33. Epiphany 2005, Krakow Tomasz Skwarnicki M1 matrix elements • Even recent calculations only marginally consistent with our upper limit on 33S1 11S0 Ebert 03 Lahde 03 13S1 11S0 23S1 11S0 23S1 11S0 33S1 21S0 allowed range 33S1 11S0 Date of publication

  34. Epiphany 2005, Krakow Tomasz Skwarnicki Inclusive y(2S)  X J/y(1S), J/y(1S)  l+l- cut cut cut cut Log scale ! MC • Large statistics, good agreement with MC precision measurement of B(y(2S)  X J/y(1S))

  35. Epiphany 2005, Krakow Tomasz Skwarnicki Exclusive y(2S)  X J/y(1S), J/y(1S)  l+l-

  36. Epiphany 2005, Krakow Tomasz Skwarnicki Exclusive y(2S)  X J/y(1S), J/y(1S)  l+l-

  37. Epiphany 2005, Krakow Tomasz Skwarnicki y(2S)  X J/y(1S), J/y(1S)  l+l- • Preliminary results presented at QWG workshop Oct 2004 • Improved results are being prepared for publication.

  38. Epiphany 2005, Krakow Tomasz Skwarnicki Exclusive hadronic y(2s) decays • A lot of theoretical complications e.g.: • Interference with continuum • as and relativistic corrections • Happy with agreements within a factor of ~2 Log scale!

  39. Epiphany 2005, Krakow Tomasz Skwarnicki Exclusive hadronic y(2s) decays CLEO y(2S) BES J/y r r • y(2s)Dalitz plot distinctively different than continuum or J/y(1S)

  40. Epiphany 2005, Krakow Tomasz Skwarnicki Exclusive hadronic y(2s) decays Linear scale

  41. Epiphany 2005, Krakow Tomasz Skwarnicki Continuum production of PV at 3.67 GeV hep-ex/0407028

  42. Epiphany 2005, Krakow Tomasz Skwarnicki Summary • First statistically compelling measurement of fD- • Observe highly significant y(2S)p0hc,hc ghcsignal with the hc mass consistent with the c.o.g. of the ccJ states • Non-observation of ggX(3872) and e+e- gX(3872). • Precision measurements of B(¡(nS) m+m-). The results for ¡(2S),¡(3S) significantly different from the PDG values, impacting estimates of the total widths of these states. • Precision measurements of photon transitions from y(2S),¡(2S),¡(3S). More sensitive tests of relativistic corrections in the potential model calculations. • Precision measurements of inclusive and exclusive transition rates for y(2S)  X J/y(1S). Some significantly different from the previous measurements. • Many new insights into B(y(2S)X)/B(J/y(1S) X) for 2- and multi-body exclusive final states. • First measurements of continuum productions of 2-body pseudo scalar-vector final states at 3.67 GeV. Ratios of cross-sections in rough agreement with SU(3) except for K*0K0

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