Multiquark States from a QCD sum rule approach with diquark effective fields

1. Multiquark States from a QCD sum rule approach with diquark effective fields Kyungil Kim, Daisuke Jido, Su Houng Lee June 22nd, 2012, Tokyo, `Heavy Quark Hadrons at J-PARC 2012’ Based on K. Kim, D. Jido, S.H.Lee PRC 84(2011)025204 K. Kim, D. Jido, S.H.Lee in preparation.

2. Motivation : Di-quark Structures in Hadrons SHLee and S.Yasui : EPJ C (2009) <Diquark inside baryons> <Quark-antiquark inside mesons> June 22nd 2012 2/14

3. Diquark Structures and Heavy-quark <Baryon> q Λ, Ξ, … h q <Tetraquark> h q h q <Pentaquark> h u u N*, Θcs, … d s <H Dibaryon> d s u s d u June 22nd 2012 3/14

4. Λ Baryons <Color-spin interaction> d u h <Current for Λ > Scalar diquark field Gauge invariant Lagrangian for diquarkfield June 22nd 2012 4/14

5. Effective Diquark Fields Gauge invariant Lagrangian for diquark field The relation between diquark condensate and gluon condensate <Propagator of diquark field> June 22nd 2012 5/14

6. QCDSR with Di-quark fields OPE Result June 22nd 2012 6/14

7. Λ Baryons Parameter Set ( ms=0.12GeV, mΛ =1.115GeV) June 22nd 2012 7/14

8. Λ Baryons <Lambda_b sum rule> <Lambda_c sum rule> June 22nd 2012 8/14

9. Ξ Baryons <Ξ_b sum rule> <Ξ_c sum rule> June 22nd 2012 9/14

10. H-dibaryon <Theoretical Prediction of H-dibaryon> <Lattice QCD results> <H-dibaryon search in STAR at RHIC> <HAL collaboration> June 22nd 2012 10/14

11. H-dibaryon <Current choice for H-dibaryon> s d u s d u <Dispersion relation> ∼ Spectral Density d s u s d u June 22nd 2012 11/14

12. OPE Result (up to Dim. 4) June 22nd 2012 12/14

13. Results in SU(3)(flavor) Sym. <Borel Curves with various threshold> June 22nd 2012 13/14

14. Summary & Outlook • The QCD sum rule approach with diquark fields gives a good result for Λs, Ξs and H-dibaryon. • We can have a diquark mass and condensate values from Lambda. • These parameters give good masses for Lmabda_c and Lambda_b. • In same approach, we can obtain the properties of ‘qs’-diquarkfrom Ξ_c. • We obtain the mass of H-dibaryon from a QCD sum rule approach with effective diquark fields. • Pentaquarks(N*,Θcs) and tetraquarks(T_cc, T_cb) are also good candidates to apply this approach. (in progress) June 22nd 2012 14/14

15. Thank you very much!!