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H- dibaryon properties from a QCD sum rule approach with diquark effective fields. Kyungil Kim. November 15 th , 2012, B usan , `ATHIC 2012’. Based on K. Kim, D. Jido , S.H.Lee PRC 84(2011)025204 K . Kim, D. Jido , S.H.Lee in preparation. Motivation : Diquarks.
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H-dibaryon properties from a QCD sum rule approach with diquark effective fields Kyungil Kim November 15th , 2012, Busan, `ATHIC 2012’ Based on K. Kim, D. Jido, S.H.Lee PRC 84(2011)025204 K. Kim, D. Jido, S.H.Lee in preparation.
Motivation : Diquarks • Quark Correlations in QCD • Confinement • Chiral symmetry breaking • Color triplet correlation between quarks • Phenomenological Evidence of Diquark • Baryon spectroscopy • Deep inelastic scattering • Quark condensation in dense matter q q q q q q q Nov. 15th 2012 1/15
Motivation : Diquark Structures in Hadrons SHLee and S.Yasui : EPJ C (2009) <Diquark inside baryons> <Quark-antiquark inside mesons> Nov. 15th 2012 2/15
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 Nov. 15th 2012 3/15
Λ Baryons <Color-spin interaction> d u h uh- and dh-interaction are cancelled by each other. <Current for Λ > Scalar diquark field Gauge invariant Lagrangian for diquarkfield Nov. 15th 2012 4/15
Effective Diquark Fields Gauge invariant Lagrangian for diquark field mΦ : diquark mass The relation between diquark condensate and gluon condensate λ : parameter for condensate <Propagator of diquark field> Single gluon with momentum Two gluons at one vertex Nov. 15th 2012 5/15
QCDSR with Di-quark fields OPE Result (up to dim. 6) Nov. 15th 2012 6/15
Λ Baryons Parameter Set ( ms=0.12GeV, mΛ =1.115GeV) Nov. 15th 2012 7/15
Λ Baryons <Lambda_b sum rule> <Lambda_c sum rule> Nov. 15th 2012 8/15
Diqaurk Masses from Various Approaches <QCD sum rule> ref/Jamin PLB238(1990)387 The mass difference between ud- and qs-diquark is ~200MeV. <Lattice QCD> <Bethe-Salpeter equation> ref/Cahill PRD 36,2804 ref/Hess PRD 58,111502 Nov. 15th 2012 9/15
Ξ Baryons <Ξ_b sum rule> <Ξ_c sum rule> Nov. 15th 2012 10/15
H-dibaryon <Theoretical Prediction of H-dibaryon> <Lattice QCD results> <H-dibaryon search in STAR at RHIC> <HAL collaboration> Nov. 15th 2012 11/15
H-dibaryon <Current choice for H-dibaryon> s d u s d u <Dispersion relation> ∼ Spectral Density d s u s d u Nov. 15th 2012 12/15
OPE Result (up to Dim. 4) Nov. 15th 2012 13/15
Results in SU(3)(flavor) Sym. <Borel Curves with various threshold> Nov. 15th 2012 14/15
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 Lambda_cand 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) Nov. 15th 2012 15/15