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Spectra and decays of hybrid charmonia. Yu.S.Kalashnikova , ITEP in collaboration with A. Nefediev , PRD77 054025 (2008). Y(4260): hybrid charmonium ?. QCD string model:. Based on Vacuum Correlator Method Confinement: gluonic correlators responsible for
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Spectra and decaysof hybrid charmonia Yu.S.Kalashnikova, ITEP in collaboration with A. Nefediev, PRD77 054025 (2008)
Y(4260): hybrid charmonium? Yu.S.Kalashnikova, ITEP
QCD string model: • Based on Vacuum Correlator Method • Confinement: gluoniccorrelators responsible for • area law asymptotic for the Wilson loop • QCD string model corresponds to the limit of small • gluonic correlation length Yu.S.Kalashnikova, ITEP
Excitations of the QCD string:qq -> “minimal” string P = (-1)L+1 C = (-1)L+S Yu.S.Kalashnikova, ITEP
Hybrid excitations:gluon with two “minimal” strings attached Yu.S.Kalashnikova, ITEP
Quantum numbers Magnetic (lg= jg) Electric (lg= jg1) Lowest magnetic Yu.S.Kalashnikova, ITEP
Zero-order Hamiltonian: • quarkonium • hybrid Yu.S.Kalashnikova, ITEP
Einbein fields: 0 -> constituent mass (calculated) Yu.S.Kalashnikova, ITEP
Spin-independent corrections: • Charmonium: • Self-energy • String correction • Hybrid: • Self-energy (the same as for cc) • String correction Yu.S.Kalashnikova, ITEP
Spin-dependent force • non-perturbative spin-orbit (Thomas) • perturbative spin-orbit • hyperfine • spin-tensor Yu.S.Kalashnikova, ITEP
Trial wavefunction • charmonium • hybrid Yu.S.Kalashnikova, ITEP
Model parameters Charmonium spectrum (MeV) Yu.S.Kalashnikova, ITEP
Zero-order hybrid mass: M00= 4573 MeV Constituent masses: c=1598 MeV, g=1085 MeV Spin-independent correction -> -90 MeV Gluon spin-orbit common for all states -> -103 MeV Yu.S.Kalashnikova, ITEP
Predictions for hybrids:1. Spin splittings Yu.S.Kalashnikova, ITEP
Predictions for hybrids:2. Mass of the vector hybrid LGT 4379 149 MeV X.-Q.Luo and Y.Liu, PRD 74 034502 (2006) Yu.S.Kalashnikova, ITEP
Predictions for hybrids:3. Masses of C-even states LGT ~ 4400 MeVC.Michael, hep-ph/0308293 4405 38 MeVY.Liu and X.-Q.Luo PRD73 054510 (2006) Yu.S.Kalashnikova, ITEP
Both these calculations and lattice place a vector hybrid at 4400 MeV Y(4260) is not a hybrid? Y(4320): Yu.S.Kalashnikova, ITEP
Strong decays of magnetic hybrids: D h D Hybrid wavefunction Q-Q = 0 for S+S mesons Yu.S.Kalashnikova, ITEP
Selection rule: D(*)D(*) hmagnetic D(*)DJ(*) Yu.S.Kalashnikova, ITEP
Vector: Mth=4327 MeV Mth=4285 MeV Yu.S.Kalashnikova, ITEP
Due to the coupling of vector • hybrid to S-wave thresholds D*D0 • and DD1 the state should be attracted • to these thresholds • If the coupling is strong enough • an extra state can be generated • dynamically Y(4260) and Y(4325) ? Yu.S.Kalashnikova, ITEP
J-+: Yu.S.Kalashnikova, ITEP
Y(4260) and Y(4320) as hybrids: No visible decays into DD pairs Small e+e- width The masses are a bit too low DD1 and D*D0 thresholds can attract the state If Y’s are hybrids, C-even partners are to be found 1-+(4320) couples strongly to D*D0 -> interesting threshold effect Yu.S.Kalashnikova, ITEP