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This article by Frank Close and Stephen Godfrey explores the spectroscopy, decay modes, and production signatures of charmonium hybrid particles in exclusive B-decays. The study investigates the properties and behaviors of various charmonium hybrids, including the 2S, 1S, and DD** states, through quenched lattice calculations and experimental measurements. The analysis includes the identification of hybrid states, their decays into charmed hadrons, and the impact of color octet contributions on production rates. The study also examines the presence of hybrid signatures in events, mass distributions of light hadrons, and backgrounds in charmonium production, providing insights into the unique properties and observable characteristics of these particles in B-decays.
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Charmonium Hybrid Production in exclusive B-decays Frank Close + Stephen Godfrey Spectroscopy Decay Production Signatures Phys Lett B574 (2003) 210
2 (cc*) Spectroscopy DD** 4280 DD* 3870 DD 3730 3686 2S: 1- 3556 2+ 3510 1+ 3415 0+ 3097 1S: 1-
3 (cc*) Hybrid Spectroscopy Quenched Lattice 1^{-+} 4.43 \pm 0.04 DD** 4280 Lattice 1^{-+} 4.04-4.4 DD* 3870 Flux tube 4.0 – 4.2 DD 3730 3686 2S: 1- 3556 2+ 3510 1+ 3415 0+ 3097 1S: 1-
4 Decays (cc*) Hybrid DD** =O(10) MeV DD** 4280 DD*; not DD; not D*D* DD* 3870 Cascade tocc*+ pions, omega, gamma DD 3730 3686 2S: 1- 3556 2+ 3510 1+ 3415 0+ Light hadrons 3097 1S: 1-
5 (cc*) Hybrid Production c c* Factorisation: cc* = 0-,1-,1+ b s K B Expt: also 0+,2+ rate like 1-,1+ ! Color octet contributions big
6 (cc*) Hybrid Production c c* Factorisation: cc* = 0-,1-,1+ b s K B Expt: also 0+,2+ rate like 1-,1+ ! Color octet contributions big Octet higher order v/c But larger Wilson coeffs. Leading behaviour for hybrids
7 (cc*) Hybrid Production c c* Estimates of rates b s K B Chiladze Falk Petrov 98 M = 4GeV but Lattice =4.7GeV reduces rate. Close Dunietz Page Veseli Yamamoto 98 = similar to conventional charmonium
8 Effect of DD** threshold
9 (cc*) Hybrid Signatures -1 Events/100fb M< DD** M>DD** 50 6 5 120 3 10 Width 1 keV. Monochromatic Also seek cc* BaBar measures so accessible
10 Mass distributions of light hadrons Decays to charmed hadrons Critical for Anomalous modes: no DD, no D*D* some DD* prominent DD**
11 Mass distributions of light hadrons Decays to charmed hadrons K(*) momentum spectrum Excess low mom K(*) recoil against 4-4.5 GeV hybrid
12 (cc*) Hybrid Backgrounds cc* with similar M and narrow widths
13 Hybrid Charmonium Production rates from B similar cc* 0.1-1% Relatively narrow Distinctive final states Observable branching ratios
Mass distributions of light hadrons; e.g. Belle see