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

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].

scholarly journals TWO-PHOTON DECAY RATES OF HEAVY QUARKONIA IN THE RELATIVISTIC QUARK MODEL

2003 ◽  
Vol 18 (09) ◽  
pp. 601-607 ◽  
Author(s):  
D. EBERT ◽  
R. N. FAUSTOV ◽  
V. O. GALKIN
Keyword(s):  
Experimental Data ◽  
Quark Model ◽  
Relativistic Effects ◽  
Decay Rates ◽  
Heavy Quarkonia ◽  
Radiative Corrections ◽  
Relativistic Quark Model ◽  
Two Photon ◽  
Photon Decay ◽  
Theoretical Predictions

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.

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

1995 ◽  
Vol 108 (7) ◽  
pp. 909-916
Author(s):  
Yu. I. Ivanshin ◽  
N. B. Skachkov
Keyword(s):  
Experimental Data ◽  
Quark Model ◽  
Relativistic Quark Model

Equilibrium similarity solution of the turbulent transport equation along the centreline of a round jet

2015 ◽  
Vol 772 ◽  
pp. 740-755 ◽  
Author(s):  
H. Sadeghi ◽  
P. Lavoie ◽  
A. Pollard
Keyword(s):  
Experimental Data ◽  
Kinetic Energy ◽  
Structure Function ◽  
Transport Equation ◽  
Power Law ◽  
Turbulent Jet ◽  
Order Structure ◽  
Current Analysis ◽  
Power Law Decay ◽  
The Mean

A novel similarity-based form is derived of the transport equation for the second-order velocity structure function of$\langle ({\it\delta}q)^{2}\rangle$along the centreline of a round turbulent jet using an equilibrium similarity analysis. This self-similar equation has the advantage of requiring less extensive measurements to calculate the inhomogeneous (decay and production) terms of the transport equation. It is suggested that the normalised third-order structure function can be uniquely determined when the normalised second-order structure function, the power-law exponent of$\langle q^{2}\rangle$and the decay rate constants of$\langle u^{2}\rangle$and$\langle v^{2}\rangle$are available. In addition, the current analysis demonstrates that the assumption of similarity, combined with an inverse relation between the mean velocity$U$and the streamwise distance$x-x_{0}$from the virtual origin (i.e. $U\propto (x-x_{0})^{-1}$), is sufficient to predict a power-law decay for the turbulence kinetic energy ($\langle q^{2}\rangle \propto (x-x_{0})^{m}$), rather than requiring a power-law decay ($m=-2$) as an additionalad hocassumption. On the basis of the current analysis, it is suggested that the mean kinetic energy dissipation rate,$\langle {\it\epsilon}\rangle$, varies as$(x-x_{0})^{m-2}$. These theoretical results are tested against new experimental data obtained along the centreline of a round turbulent jet as well as previously published data on round jets for$11\,000\leqslant \mathit{Re}_{D}\leqslant 184\,000$over the range$10\leqslant x/D\leqslant 90$. For the present experiments,$\langle q^{2}\rangle$exhibits power-law behaviour with$m=-1.83$. The validity of this solution is confirmed using other experimental data where$\langle q^{2}\rangle$follows a power law with$-1.89\leqslant m\leqslant -1.78$. The present similarity form of the transport equation for$\langle ({\it\delta}q)^{2}\rangle$is also shown to be closely satisfied by the experimental data.

scholarly journals Heavy Baryon Spectroscopy in the Relativistic Quark Model

Particles ◽  
2020 ◽  
Vol 3 (1) ◽  
pp. 234-244 ◽  
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.

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

2012 ◽  
Vol 27 (31) ◽  
pp. 1250183 ◽  
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*).

scholarly journals Decays of light mesons in the relativistic quark model

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.

scholarly journals Ground-state masses and magnetic moments of heavy baryons

2014 ◽  
Vol 29 (20) ◽  
pp. 1450106 ◽  
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.

FINITE-SIZE CORRECTIONS TO CORRELATION FUNCTION AND SUSCEPTIBILITY IN 2D ISING MODEL

2006 ◽  
Vol 17 (08) ◽  
pp. 1095-1105 ◽  
Author(s):  
J. KAUPUŽS
Keyword(s):  
Correlation Function ◽  
Ising Model ◽  
Correction Term ◽  
Finite Size ◽  
Scaling Exponent ◽  
Corrections To Scaling ◽  
Perfect Agreement ◽  
Point Correlation ◽  
Point Correlation Function ◽  
Correction To Scaling

Transfer matrix calculations of the critical two-point correlation function in 2D Ising model on a finite-size [Formula: see text] lattice with periodic boundaries along 〈11〉 direction are extended to L = 21. A refined analysis of the correlation function in 〈10〉 crystallographic direction at the distance r = L indicates the existence of a nontrivial finite-size correction of a very small amplitude with correction-to-scaling exponent ω < 2 in agreement with our foregoing study for L ≤ 20. Here we provide an additional evidence and show that amplitude a of the multiplicative correction term 1 + aL-ω is about -3.5·10-8 if ω = 1/4 (the expected value). We calculate also the susceptibility for L ≤ 18 in order to compare our numerical estimates for the constant background contribution with the known very precise value and to look for possible nontrivial corrections to scaling. The numerical analysis reveals a perfect agreement for the background term, as well as shows that the nontrivial correction term, detected by our analysis in the correlation function, likely cancels in the susceptibility.

scholarly journals Heavy Tetraquarks in the Relativistic Quark Model

Universe ◽  
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.

Sign in / Sign up

Export Citation Format

Share Document