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arXiv · hep-lat/0703019

Scalar-Quark Systems and Chimera Hadrons in SU(3)_c Lattice QCD

H. Iida·H. Suganuma·T. T. Takahashi
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Abstract

Light scalar-quarks ϕ(colored scalar particles or idealized diquarks) and their color-singlet hadronic states are studied with quenched SU(3)_c lattice QCD in terms of mass generation in strong interaction without chiral symmetry breaking. We investigate ``scalar-quark mesons'' ϕ^\dagger ϕand ``scalar-quark baryons'' ϕϕϕwhich are the bound states of scalar-quarks ϕ. We also investigate the bound states of scalar-quarks ϕand quarks ψ, i.e., ϕ^\dagger ψ, ψψϕand ϕϕψ, which we name ``chimera hadrons''. All the new-type hadrons including ϕare found to have a large mass even for zero bare scalar-quark mass m_ϕ=0 at a^{-1}\simeq 1GeV. We find that the constituent scalar-quark and quark picture is satisfied for all the new-type hadrons. Namely, the mass of the new-type hadron composed of m ϕ's and n ψ's, M_{{m}ϕ+{n}ψ}, satisfies M_{{m}ϕ+{n}ψ}\simeq {m} M_ϕ+{n} M_ψ, where M_ϕand M_ψare the constituent scalar-quark and quark mass, respectively. M_ϕat m_ϕ=0 estimated from these new-type hadrons is 1.5-1.6GeV, which is larger than that of light quarks, M_ψ\simeq 400{\rm MeV}. Therefore, in the systems of scalar-quark hadrons and chimera hadrons, scalar-quarks acquire large mass due to large quantum corrections by gluons. Together with other evidences of mass generations of glueballs and charmonia, we conjecture that all colored particles generally acquire a large effective mass due to dressed gluon effects.

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H. Iida, H. Suganuma, T. T. Takahashi. 2007-05-28. Scalar-Quark Systems and Chimera Hadrons in SU(3)_c Lattice QCD. https://doi.org/10.1103/physrevd.75.114503

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