350 likes | 523 Views
EIC workshop@Weihai. Heavy quark exotica and heavy quark symmetry. Yan-Rui Liu ( 刘言锐 ) Shandong University, China Jul. 29, 2013. EIC workshop@Weihai. Content. Heavy quark mesons Heavy quark symmetry Predictions Summary and perspective. EIC workshop@Weihai. Quark model and hadrons.
E N D
EIC workshop@Weihai Heavy quark exotica and heavy quark symmetry Yan-Rui Liu (刘言锐) Shandong University, China Jul. 29, 2013
EIC workshop@Weihai Content • Heavy quark mesons • Heavy quark symmetry • Predictions • Summary and perspective
EIC workshop@Weihai Quark model and hadrons Heavy quark hadrons
EIC workshop@Weihai Heavy quark hadrons
EIC workshop@Weihai Heavy quark spectra from • Belle, Babar, CDF, SELEX, LHCb, BESIII, ... • Future: Higgs-factory, Z-factory, STCF, EIC?
EIC workshop@Weihai Exotic -like mesons PDG12
EIC workshop@Weihai • Above DD threshold • Near threshold, coupled channel effects • Difficult to understand in QM
EIC workshop@Weihai Exotic -like mesons • Easier to produce than , ... A deuteron-like molecule?
EIC workshop@Weihai Exotic -like mesons BESIII: + X(3872) + charged states
EIC workshop@Weihai Charged exotic mesons • Zb(10610), Zb(10650): PRL 108, 122001 (2012) [Belle]
EIC workshop@Weihai Exotic mesons: interpretations • Molecule or tetraquark? e.g. Y(4260) & Z(3900) • Hybrids? • Cusp? • Threshold effect? • Coupled channel effects? • ...
EIC workshop@Weihai Y(4260) & Zc(3900) Q. Wang, C. Hanhart, Q. Zhao, 1303.6355 D.Y. Chen, X. Liu, T. Matsuki, 1304.5845
EIC workshop@Weihai QCD and heavy quark symmetry • QCD: hadrons • u < d < s < c < b < t • mq0, chiral symmetry, K • mQ, heavy quark symmetry (HQS) :Simple but important , need more studies
EIC workshop@Weihai Heavy quark symmetry • For a heavy quark Q interacting with light degrees of freedom, such as light quarks and gluons • Strong interactions: (1) flavor blind HQ flavor symmetry (HQFS) (2) heavy quark spin orientation blind HQ spin symmetry (HQSS)
EIC workshop@Weihai Heavy quark symmetry • HQFS • HQSS
EIC workshop@Weihai Heavy quark symmetry(Multiplet structure) both conserved
EIC workshop@Weihai Heavy quark symmetry(Multiplet structure)
EIC workshop@Weihai Heavy quark symmetry(Multiplet structure) • Q-hadron ?
EIC workshop@Weihai HQSS constraints • For interactions: EFT HQSS • For molecule decays: spin selection rules • For molecule production in annihilation: total angular momentum of light degree of freedom should be 0 • ... T.M. Yan et a l., prd46,1148 (1992)
EIC workshop@Weihai HQS selection rules inmeson-antimeson structure M.B. Voloshin, PLB 604,69; Y.R. Liu, 1304.7467
EIC workshop@Weihai HQS selection rules • Two selection rules for in S-wave meson-antimeson states in HQ limit: (a) (b) if (A,B) is a doublet • Same rules for S-wave baryon-antibaryon states with the exception for two singlet baryons where • Heavy quark limit: conserved in strong decays of hadron-antihadron states
EIC workshop@Weihai HQS selection rules X(3872) Not observed Zc(3900) Not observed If no, maybe a tetraquark
EIC workshop@Weihai HQS selection rules If Y(3940) is a molecule, c channelJ=0 or 2. A charged state in J/? J=1 A charged state in J/? c: J=0 or 2
EIC workshop@Weihai HQS selection rules J=1: J=2: J=3: cf. Probability for spin(cc)=0 in DD1 is 1/8
EIC workshop@Weihai HQS in molecule production X. Li, M.B. Voloshin, 1307.1072 • Heavy quark spin symmetry • Y(4260) as a molecule is not supported • How large is the HQSS violation in decay and production?
EIC workshop@Weihai Predictions of new exotica Tornqvist’s predictions in Z. Phys. C 61, 525 (1994) One-pion exchange approach including tensor force
EIC workshop@Weihai Predictions of new exotica • More meson-antimeson molecules are possible: H-H, H-S, ...
EIC workshop@Weihai Predictions of new exotica • X3 rearrangement decays to : J=1,2,3, P=-, C= Z3, Z2, Z1; X3, X2, X1 For C=+ case, attraction strong for X3 state HQSS Around the threshold, the J/ channel may be used to identify X3 with
D.Y. Chen, Xiang Liu, T. Matsuki, arXiv:1306.2080 The similarity between Y(4360) and Y(4260) Novel charged charmoniumlike structures in the hidden-charm dipion decays of Y(4360) Xiang Liu @ STCF: ISPE mechanism
EIC workshop@Weihai More on heavy quark hadrons • Tcc: tetraquark with quark content (ccqq) • cc, cN, cc, ... • Hidden charm N*: mass > 4200 MeV NOT excited nucleon: exotic property [Wu, Molina, Oset, Zou, PRL 105, 232001 (2010)] • Anomalous line shape in • ...
EIC workshop@Weihai Summary and perspective • Lots of unexpected observations have been made • More interesting phenomena above DD threshold are expected • Heavy quark (spin) symmetry plays an important role in understanding heavy quark exotica and might lead to more findings • Need more information from experiments: Higgs-factory, Z-factory, STCF and/or EIC? Thank you!