BARYONS AS SOLITONS IN THREE-DIMENSIONAL QUANTUM CHROMODYNAMICS

We show that baryons of three-dimensional quantum chromodynamics can be understood as solitons of its effective Lagrangian. In the parity-preserving phase we study, these baryons are fermions for odd Nc and bosons for even Nc, never anyons. We quantize the collective variables of the solitons and thereby calculate the flavor quantum numbers. magnetic moments and mass splittings of the baryon. The flavor quantum numbers are in agreement with naive quark model for the low-lying states. The magnetic moments and mass splittings are smaller in the soliton model by a factor of logFπ/Ncmπ. We also show that there is a dibaryon solution that is an analog of the deuteron. These solitons can describe defects in a quantum antiferromagnet.

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THE EFFECTIVE LAGRANGIAN OF THREE DIMENSIONAL QUANTUM CHROMODYNAMICS

International Journal of Modern Physics A ◽

10.1142/s0217751x92003616 ◽

1992 ◽

Vol 07 (32) ◽

pp. 7989-8000 ◽

Cited By ~ 9

Author(s):

G. FERRETTI ◽

S.G. RAJEEV ◽

Z. YANG

Keyword(s):

Quantum Chromodynamics ◽

Sigma Model ◽

Three Dimensional ◽

Low Energy ◽

Nonlinear Sigma Model ◽

Flavor Symmetry ◽

Energy Limit ◽

Long Wavelength ◽

Effective Lagrangian ◽

Chern Simons

We consider the low energy limit of three dimensional quantum chromodynamics (QCD) with an even number of flavors. We show that parity is not spontaneously broken, but the global (flavor) symmetry is spontaneously broken. The low energy effective Lagrangian is a nonlinear sigma model on the Grassmannian. Some Chern-Simons terms are necessary in the Lagrangian to realize the discrete symmetries correctly. We consider also another parametrization of the low energy sector which leads to a three dimensional analogue of the Wess-Zumino-Witten-Novikov model. Since three dimensional QCD is believed to be a model for quantum antiferromagnetism, our effective Lagrangian can describe their long wavelength excitations (spin waves).

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Sea Contributions to Spin 1/2 Baryon Structure, Magnetic Moments, and Spin Distribution

International Journal of Modern Physics A ◽

10.1142/s0217751x97001171 ◽

1997 ◽

Vol 12 (10) ◽

pp. 1861-1874 ◽

Cited By ~ 4

Author(s):

V. Gupta ◽

R. Huerta ◽

G. Sánchez-Colón

Keyword(s):

Wave Function ◽

Numerical Analysis ◽

Quark Model ◽

Magnetic Moment ◽

Composite System ◽

Magnetic Moments ◽

Spin Distribution ◽

Quantum Numbers ◽

Experimental Errors ◽

Spin Distributions

We treat the baryon as a composite system made out of a "core" of three quarks (as in the standard quark model) surrounded by a "sea" (of gluons and [Formula: see text]-pairs) which is specified by its total quantum numbers like flavor, spin and color. Specifically, we assume the sea to be a flavor octet with spin 0 or 1 but no color. The general wave function for spin 1/2 baryons with such a sea component is given. Application to the magnetic moments is considered. Numerical analysis shows that a scalar (spin 0) sea with an admixture of a vector (spin 1) sea can provide very good fits to the magnetic moment data using experimental errors. These fit also give reasonable values for the spin distributions of the proton and neutron.

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MASSES, MAGNETIC MOMENTS, AND SEMILEPTONIC DECAYS OF SPIN-1/2 BARYONS WITH SEA CONTRIBUTION

Modern Physics Letters A ◽

10.1142/s0217732398003065 ◽

1998 ◽

Vol 13 (36) ◽

pp. 2887-2901

Author(s):

V. GUPTA ◽

P. RITTO ◽

G. SÁNCHEZ-COLÓN

Keyword(s):

Quark Model ◽

Reasonable Agreement ◽

Composite System ◽

Magnetic Moments ◽

Semileptonic Decays ◽

Nucleon Spin ◽

Quantum Numbers ◽

Simple Quark Model ◽

Spin Distributions

The spin-1/2 baryons are pictured as a composite system made out of a "core" of three valence quarks (as in the simple quark model) surrounded by a "sea" (of gluon and [Formula: see text] pairs) which is specified by its total quantum numbers. We assume that the sea is an SU(3) flavor octet with spin 0 or 1 but no color. This model, considered earlier, is used to obtain simultaneous fits for masses, magnetic moments and GA/GV for semileptonic decays. These fits give predictions for nucleon spin distributions in reasonable agreement with experiment.

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The Genuine Resonance of Full-Charm Tetraquarks

Universe ◽

10.3390/universe7050155 ◽

2021 ◽

Vol 7 (5) ◽

pp. 155

Author(s):

Xiaoyun Chen

Keyword(s):

Quark Model ◽

Bound States ◽

Expansion Method ◽

Chiral Quark Model ◽

Stabilization Method ◽

Scaling Method ◽

Resonance States ◽

Gaussian Expansion Method ◽

Color Structure ◽

Quantum Numbers

In this work, the genuine resonance states of full-charm tetraquark systems with quantum numbers JPC=0++,1+−,2++ are searched in a nonrelativistic chiral quark model with the help of the Gaussian Expansion Method. In this calculation, two structures, meson-meson and diquark–antidiquark, as well as their mixing with all possible color-spin configurations, are considered. The results show that no bound states can be formed. However, resonances are possible because of the color structure. The genuine resonances are identified by the stabilization method (real scaling method). Several resonances for the full-charm system are proposed, and some of them are reasonable candidates for the full-charm states recently reported by LHCb.

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Baryon magnetic moments in the covariant oscillator quark model with unequal constituent masses

Physical Review D ◽

10.1103/physrevd.28.2918 ◽

1983 ◽

Vol 28 (11) ◽

pp. 2918-2921 ◽

Cited By ~ 3

Author(s):

Shin Ishida ◽

Kenji Yamada ◽

Masuho Oda

Keyword(s):

Quark Model ◽

Magnetic Moments

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Comment on “Octet baryon magnetic moments in the chiral quark model with configuration mixing”

Physical Review D ◽

10.1103/physrevd.61.098301 ◽

2000 ◽

Vol 61 (9) ◽

Cited By ~ 7

Author(s):

Jerrold Franklin

Keyword(s):

Quark Model ◽

Magnetic Moments ◽

Chiral Quark Model ◽

Octet Baryon ◽

Configuration Mixing

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STRUCTURE OF LIGHT AND HEAVY PENTAQUARKS

International Journal of Modern Physics A ◽

10.1142/s0217751x05023359 ◽

2005 ◽

Vol 20 (08n09) ◽

pp. 1797-1802 ◽

Cited By ~ 2

Author(s):

FL. STANCU

Keyword(s):

Variational Method ◽

Hyperfine Interaction ◽

Quark Model ◽

Constituent Quark ◽

Constituent Quark Model ◽

Positive Parity ◽

Model Based ◽

Quantum Numbers ◽

The Masses

Light and heavy pentaquarks are described within a constituent quark model based on a spin-flavor hyperfine interaction. In this model the lowest state acquires positive parity. The masses of the light antidecuplet members are calculated dynamically using a variational method. It is shown that the octet and antidecuplet states with the same quantum numbers mix ideally due to SU (3)F breaking. Masses of the charmed antisextet pentaquarks are predicted within the same model.

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Charmonia production in W → (cc̄)Ds(∗) decays

Modern Physics Letters A ◽

10.1142/s0217732321500589 ◽

2021 ◽

Vol 36 (09) ◽

pp. 2150058

Author(s):

A. V. Luchinsky ◽

A. K. Likhoded

Keyword(s):

Quantum Chromodynamics ◽

Light Cone ◽

Relativistic Quantum ◽

Branching Fractions ◽

Color Singlet ◽

Leading Order ◽

Paper Production ◽

Quantum Numbers ◽

Numerical Predictions ◽

State Formula

In this paper, production of charmonium state [Formula: see text] in exclusive [Formula: see text] decays is analyzed in the framework of both leading order Non-relativistic Quantum Chromodynamics (NRQCD) and light-cone (LC) expansion models. Analytical and numerical predictions for the branching fractions of these decays in both the approaches are given. The typical value of the branching fractions is [Formula: see text][Formula: see text][Formula: see text] and it turns out that the LC results are significantly larger than NRQCD ones (approximately two or four times increase depending on the quantum numbers of the final particles), so the effect of internal quark motion should be taken into account. Some rough estimates of color-octet contributions are presented and it is shown that these contributions could be comparable with color-singlet results.

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Soliton Model of the Photon / Fotona Solitona Modelis

Latvian Journal of Physics and Technical Sciences ◽

10.2478/lpts-2013-0013 ◽

2013 ◽

Vol 50 (2) ◽

pp. 60-67 ◽

Cited By ~ 4

Author(s):

I. Bersons

Keyword(s):

Nonlinear Equation ◽

Soliton Solution ◽

Vector Potential ◽

Maxwell Equations ◽

Three Dimensional ◽

Soliton Model ◽

Dimensionless Constant ◽

Dimensional Object ◽

Dimensional Soliton ◽

Wave Properties

A three-dimensional soliton model of photon with corpuscular and wave properties is proposed. We consider the Maxwell equations and assume that light induces the polarization and magnetization of vacuum only along the direction of its propagation. The nonlinear equation constructed for the vector potential is similar to the generalized nonlinear Schrödinger equation and comprises a dimensionless constant μ that determines the size-scale of soliton and is expected to be small. The obtained one-soliton solution of the proposed nonlinear equation describes a three-dimensional object identified as photon.

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