Search arXiv⌕ Search

arXiv · hep-lat/0703019

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

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.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

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

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

Efficient Quantum Simulations of Yang-Mills theory with Maximal-tree Gauge

We develop a quantum algorithmic framework for the efficient simulation of Yang--Mills theories, including the $\mathrm{SU}(3)$ gauge theory in Quantum Chromodynamics (QCD). The framework uses maximal-tree gauge in terms of gauge field variables that removes all local gauge redundancies. In the resulting gauge-fixed formulation and digitization in the field-amplitude basis, we show that Hamiltonian time evolution admits an efficient implementation based on quantum singular value transformation (QSVT). We derive upper bounds on the total number of qubits and gate complexity, finding polynomial scaling with the inverse simulation precision $1/\varepsilon_s$, lattice volume $\mathcal{V}$, gauge coupling $g$, and target energy scale $E$. Our results provide a rigorous complexity-theoretic demonstration that non-Abelian Yang--Mills theories can be simulated efficiently on quantum computers, paving the way toward first-principles quantum simulations of non-perturbative QCD dynamics.

hep-lat↗

Accurate Sampling from Diffusion Models

A new proposal called DM-SMC (Diffusion Model - Sequential Monte Carlo) is investigated, which samples ensembles defined in terms of an action, using diffusion models trained on samples from the ensemble. The SMC setup allows for accurate sampling in spite of an approximate diffusion model and the finite stepsize used in the numerical solution of the stochastic process. Improved update strategies are also investigated. Results are presented for a $Z_2$ symmetric scalar field theory in 2 dimensions near its 2nd order phase transition.

hep-lat↗

Decomposition of the axial-vector current in a finite box

We consider the matrix element of the axial-vector current between two nucleon states in a finite box. Starting from the chiral Lagrangian density with nucleon and Delta-isobar degrees of freedom, we study the finite-volume effects at the one-loop level. We show that the standard decomposition into the axial-vector and pseudoscalar form factor is incomplete in a finite box. We derive expressions for the complete set of in-box form factors at one loop, and demonstrate how to extract the full set from lattice correlation functions. We verify that the axial Ward identity holds in the chiral limit. We derive the one-loop expressions for the pseudoscalar form factor and verify that the in-box axial Ward identity away from the chiral limit is fulfilled also. Selected numerical results are shown for two flavor-SU(2) lattice ensembles. Sizable finite-volume effects are observed, with an important role for the Delta-isobar. We discuss the implications of our results for lattice studies of the axial-vector current. We conclude that full finite-box results are crucial for a precise determination of the form factors.

hep-lat↗