Relativistic quark model and new experimental data on π- and ρ-Meson resonances

Two-photon decay rates of pseudoscalar, scalar and tensor states of charmonium and bottomonium are calculated in the framework of the relativistic quark model. Both relativistic effects and one-loop radiative corrections are taken into account. The obtained results are compared with other theoretical predictions and available experimental data.

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STUDY OF POWER-LAW CORRECTIONS TO SCALING IN A RELATIVISTIC QUARK MODEL

International Journal of Modern Physics A ◽

10.1142/s0217751x90001161 ◽

1990 ◽

Vol 05 (13) ◽

pp. 2591-2604

Author(s):

L. S. CELENZA ◽

A. PANTZIRIS ◽

C. M. SHAKIN ◽

HUI-WEN WANG

Keyword(s):

Experimental Data ◽

Structure Function ◽

Quark Model ◽

Power Law ◽

Correction Term ◽

Analytic Form ◽

Recent Analysis ◽

Relativistic Quark Model ◽

Corrections To Scaling ◽

Correction To Scaling

We study the approach to scaling in a relativistic quark model which we have used previously to fit the experimental data for the structure function [Formula: see text] (for all x) and for [Formula: see text] (for x > 0.4). We present values for these structure functions calculated in our model and also present an analytic form which provides a good fit to the numerical results. Our model supports one form of the power-law corrections suggested in the literature. [We reproduce the sign and magnitude of the parameter which appears in a phenomenological form used in a recent analysis made by the BEBC Collaboration. Our results are also consistent with a recent BCDMS Collaboration analysis which finds no need for "higher-twist" terms for Q2 > 20 (Gev) 2.] We also discuss certain complications which may arise when one attempts to study "higher-twist" behavior at both small and large x with a single sign for the phenomenological power-law correction term. (In particular, we predict a change in sign of the power-law correction to scaling between x = 0.65 and x = 0.7.) In addition, we calculate R(x, Q2) and find a good fit to the experimental data using the same parameters which were used in our fits to [Formula: see text] and [Formula: see text].

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Heavy Baryon Spectroscopy in the Relativistic Quark Model

Particles ◽

10.3390/particles3010019 ◽

2020 ◽

Vol 3 (1) ◽

pp. 234-244 ◽

Cited By ~ 2

Author(s):

Rudolf N. Faustov ◽

Vladimir O. Galkin

Keyword(s):

Experimental Data ◽

Quark Model ◽

Heavy Baryon ◽

Lhcb Collaboration ◽

Relativistic Quark Model ◽

Quantum Numbers ◽

Heavy Baryons ◽

Baryon Spectroscopy ◽

Good Agreement

Masses of heavy baryons are calculated in the framework of the relativistic quark-diquark picture and QCD. The obtained results are in good agreement with available experimental data including recent measurements by the LHCb Collaboration. Possible quantum numbers of excited heavy baryon states are discussed.

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EXCLUSIVE WEAK B DECAYS INVOLVING τ LEPTON IN THE RELATIVISTIC QUARK MODEL

Modern Physics Letters A ◽

10.1142/s0217732312501830 ◽

2012 ◽

Vol 27 (31) ◽

pp. 1250183 ◽

Cited By ~ 14

Author(s):

R. N. FAUSTOV ◽

V. O. GALKIN

Keyword(s):

Experimental Data ◽

Quark Model ◽

Branching Fractions ◽

Relativistic Quark Model ◽

B Decays ◽

Error Bars

Semileptonic and leptonic B decays are analyzed in the framework of the relativistic quark model. Special attention is paid to the decays involving τ lepton. It is found that the calculated particular decay branching fractions are consistent with available experimental data within error bars. However, the predicted and recently measured ratios R(D(*)) of the B→D(*)τντ and B→D(*)lνl branching fractions differ by 1.75σ for R(D) and by 2.4σ for R(D*).

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Decays of light mesons in the relativistic quark model

Proceedings of the National Academy of Sciences of Belarus Physics and Mathematics Series ◽

10.29235/1561-2430-2019-55-3-325-337 ◽

2019 ◽

Vol 55 (3) ◽

pp. 325-337

Author(s):

V. Yu. Haurysh ◽

V. V. Andreev

Keyword(s):

Experimental Data ◽

Quark Model ◽

Radiative Decay ◽

Form Factors ◽

Integral Representations ◽

Relativistic Quark Model ◽

Vector Mesons ◽

Resonance Effects ◽

Decay Constants ◽

Oscillator Wave Function

In the framework of the relativistic quark model based on the point form of the Poincaré-invariant quantum mechanics, the parameters were fixed using the integral representations of the lepton decay constants of pseudoscalar and vector mesons containing u-, d- and s-quarks. As a result of numerical calculations using the oscillator wave function, the basic parameters of the model are obtained using the pseudoscalar density constant and current quark masses. The analysis showed that the obtained calculation results in the framework of the model and the experimental data on the lepton decays of hadrons agree well with each other. As a result, the calculation method is generalized to the case of hadronic transitions with γ-quantum emission and a subsequent calculation of the integral representations of radiative decay constants of pseudoscalar and vector mesons. The obtained values of the anomalous magnetic moments are compared with the baryon data. As a test of the model, the authors studied the behavior of the form-factors of radiative decays of vector mesons with a subsequent comparison to the modern experimental data in the q < 0.5 GeV range where the resonance effects are insignificant. As a result, self-consistent descriptions of lepton and radiative transitions were obtained within the framework of the model proposed by the authors.

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Ground-state masses and magnetic moments of heavy baryons

Modern Physics Letters A ◽

10.1142/s0217732314501065 ◽

2014 ◽

Vol 29 (20) ◽

pp. 1450106 ◽

Cited By ~ 24

Author(s):

Zahra Ghalenovi ◽

Ali Akbar Rajabi ◽

Si-xue Qin ◽

Dirk H. Rischke

Keyword(s):

Experimental Data ◽

Hyperfine Interaction ◽

Quark Model ◽

Ground State ◽

Magnetic Moments ◽

Heavy Flavor ◽

Relativistic Quark Model ◽

Heavy Baryons ◽

Hypercentral Approach ◽

Good Agreement

In this work, we study single, double and triple heavy-flavor baryons using the hypercentral approach in the framework of the non-relativistic quark model. Considering two different confining potentials and an improved form of the hyperfine interaction, we calculate the ground-state masses of heavy baryons and also the ground-state magnetic moments of single charm and beauty baryons with JP = 3/2+. The obtained results are in good agreement with experimental data and those of other works.

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Heavy Tetraquarks in the Relativistic Quark Model

Universe ◽

10.3390/universe7040094 ◽

2021 ◽

Vol 7 (4) ◽

pp. 94

Author(s):

Rudolf N. Faustov ◽

Vladimir O. Galkin ◽

Elena M. Savchenko

Keyword(s):

Experimental Data ◽

Form Factor ◽

Mass Spectrum ◽

Quark Model ◽

Detailed Comparison ◽

Lhcb Collaboration ◽

Relativistic Quark Model ◽

Quasipotential Approach ◽

The Masses ◽

Gluon Interaction

We give a review of the calculations of the masses of tetraquarks with two and four heavy quarks in the framework of the relativistic quark model based on the quasipotential approach and QCD. The diquark-antidiquark picture of heavy tetraquarks is used. The quasipotentials of the quark-quark and diquark-antidiquark interactions are constructed similarly to the previous consideration of mesons and baryons. Diquarks are considered in the colour triplet state. It is assumed that the diquark and antidiquark interact in the tetraquark as a whole and the internal structure of the diquarks is taken into account by the calculated form factor of the diquark-gluon interaction. All parameters of the model are kept fixed from our previous calculations of meson and baryon properties. A detailed comparison of the obtained predictions for heavy tetraquark masses with available experimental data is given. Many candidates for tetraquarks are found. It is argued that the structures in the di-J/ψ mass spectrum observed recently by the LHCb collaboration can be interpreted as ccc¯c¯ tetraquarks.

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