scholarly journals EXCITED PIONS, ρ- AND ω-MESONS AND THEIR DECAYS IN A CHIRAL SU(2) × SU(2) LAGRANGIAN

1998 ◽  
Vol 13 (32) ◽  
pp. 5443-5457 ◽  
Author(s):  
M. K. VOLKOV ◽  
D. EBERT ◽  
M. NAGY
Keyword(s):  
Experimental Data ◽  
Excited State ◽  
Decay Constant ◽  
Three Dimensional ◽  
Form Factors ◽  
Weak Decay ◽  
Wave Functions ◽  
Spontaneous Breaking ◽  
Gap Equation ◽  
Decay Widths

A chiral SU(2) × SU(2) Lagrangian containing, besides the usual meson fields, their first radial excitations is considered. The Lagrangian is derived by bosonization of the Nambu–Jona-Lasinio (NJL) quark model with separable nonlocal interactions, with form factors corresponding to three-dimensional ground and excited state wave functions. The spontaneous breaking of chiral symmetry is governed by the NJL gap equation. The first radial excitations of the pions, ρ-and ω-mesons are described with the help of two form factors. The weak decay constant Fπ′ is calculated. The values for the decay widths of the processes ρ→2π, π′→ρπ, ρ′→2π, ρ′→ωπ and ω′→ρπ are obtained in agreement with the experimental data.

Determination of hyperon properties through the variational method considering the hyperfine interaction

2019 ◽  
Vol 28 (10) ◽  
pp. 1950087 ◽  
Author(s):  
S. M. Moosavi Nejad ◽  
A. Armat
Keyword(s):  
Experimental Data ◽  
Wave Function ◽  
Ground State ◽  
Radiative Decay ◽  
Magnetic Moments ◽  
Wave Functions ◽  
Decay Widths ◽  
Free Parameters ◽  
Theoretical Results

Performing a fit procedure on the hyperon masses, we first determine the free parameters in the Cornell-like hypercentral potential between the constituent quarks of hyperons in their ground state. To this end, using the variational principle, we apply the hyperspherical Hamiltonian including the Cornell-like hypercentral potential and the perturbation potentials due to the spin–spin, spin–isospin and isospin–isospin interactions between constituent quarks. In the following, we compute the hyperon magnetic moments as well as radiative decay widths of spin-3/2 hyperons using the spin-flavor wave function of hyperons. Our analysis shows acceptable consistencies between theoretical results and available experimental data. This leads to reliable wave functions for hyperons at their ground state.

Inelastic electric and magnetic electron scattering form factors of 24Mg nucleus: Role of g factors

2017 ◽  
Vol 26 (05) ◽  
pp. 1750032 ◽  
Author(s):  
Anwer A. Al-Sammarraie ◽  
M. L. Inche Ibrahim ◽  
Muna Ahmed Saeed ◽  
Fadhil I. Sharrad ◽  
Hasan Abu Kassim
Keyword(s):  
Experimental Data ◽  
Electron Scattering ◽  
Form Factors ◽  
Wave Functions ◽  
Matrix Elements ◽  
Model Hamiltonian ◽  
Transverse Electron ◽  
Magnetic Electron ◽  
Good Agreement

The electric and magnetic transitions in the [Formula: see text]Mg nucleus are studied based on the calculations of the longitudinal and the transverse electron scattering form factors. The universal sd-shell model Hamiltonian (USDA) is used for calculations. The wave functions of radial single-particle matrix elements are calculated using the Skyrme potential. For the longitudinal form factors, a good agreement is obtained between the calculations and the experimental data. For the transverse form factors, the effective [Formula: see text] factors are made as adjustable parameters in order to describe the experimental data.

scholarly journals ANALYSIS OF THE $B_q\to D_q(D_q^*)P$ AND $B_q\to D_q(D_q^*)V$ DECAYS WITHIN THE FACTORIZATION APPROACH IN QCD

2009 ◽  
Vol 24 (31) ◽  
pp. 5845-5860 ◽  
Author(s):  
K. AZIZI ◽  
R. KHOSRAVI ◽  
F. FALAHATI
Keyword(s):  
Experimental Data ◽  
Perturbative Qcd ◽  
Sum Rules ◽  
Branching Fraction ◽  
Form Factors ◽  
Transition Form ◽  
Qcd Sum Rules ◽  
Factorization Approach ◽  
Electroweak Penguin ◽  
Decay Widths

Using the factorization approach and considering the contributions of the current–current, QCD penguin and electroweak penguin operators at the leading approximation, the decay amplitudes and decay widths of [Formula: see text] and [Formula: see text] transitions, where q = u, d, s and P and V are pseudoscalar and vector mesons, are calculated in terms of the transition form factors of the Bq→Dq and [Formula: see text]. Having computed those form factors in three-point QCD sum rules, the branching fraction for these decays are also evaluated. A comparison of our results with the predictions of the perturbative QCD as well as the existing experimental data is presented.

Calculation of the energy levels and charge radius of 24Mg and 32S isotopes in the cluster model

2020 ◽  
Vol 98 (2) ◽  
pp. 148-152
Author(s):  
Sahar Aslanzadeh ◽  
Mohammad Reza Shojaei ◽  
Ali Asghar Mowlavi
Keyword(s):  
Experimental Data ◽  
Excited State ◽  
Cluster Model ◽  
Yukawa Potential ◽  
Energy Levels ◽  
Alpha Particles ◽  
Wave Functions ◽  
S Isotopes ◽  
Klein Gordon ◽  
Nu Method

In this work, the 24Mg and 32S isotopes are considered in the cluster model by solving the Schrödinger and Klein–Gordon equations using the Nikiforov–Uvarov (NU) method. The configuration of the alpha particles for the second excited state for 24Mg isotope is 12C + 12C. A local potential is used for these two equations that is compatible to the modified Hulthen plus quadratic Yukawa potential. By substituting this potential in the Schrödinger and Klein–Gordon equations, the energy levels and wave functions are obtained. The calculated results from the Schrödinger and Klein–Gordon equations, i.e., nonrelativity and relativity, respectively, are close to the results from experimental data.

Spontaneous breaking of reflexional symmetry in real quasi-two-dimensional turbulence: stochastic travelling waves and helical solitons in atmosphere and laboratory

1993 ◽  
Vol 441 (1911) ◽  
pp. 147-155 ◽  
Keyword(s):  
Experimental Data ◽  
Boundary Layer ◽  
Laboratory Experiments ◽  
Travelling Waves ◽  
Qualitative Difference ◽  
Three Dimensional ◽  
Spontaneous Breaking ◽  
Two Dimensional ◽  
Boundary Layer Turbulence ◽  
The Difference

The theme of this note is the qualitative difference between strictly two-dimensional (2D) and quasi-two-dimensional (Q2D) turbulence in spite of the ‘smallness’ of the difference in their geometry. It is argued that the Q2D régime arises as a result of a spontaneous breaking of reflexional symmetry, which in turn is a consequence of the instability of 2D turbulence to three-dimensional helical travelling waves and solitons (through super-critical and sub-critical bifurcations). The difference between 2D and Q2D turbulence, which is primarily of a topological nature (related to helicity and super helicity) is manifested in different spectral and diffusive properties. The arguments are supported by a large number of experimental data from laboratory experiments (stably stratified, rotating, magnetohydrodynamic and boundary layer turbulence) and from observations in the stratosphere.

scholarly journals MESON DECAY IN AN INDEPENDENT QUARK MODEL

2000 ◽  
Vol 09 (05) ◽  
pp. 407-415 ◽  
Author(s):  
HAKAN CİFTCİ ◽  
HÜSEYIN KORU
Keyword(s):  
Experimental Data ◽  
Quark Model ◽  
Weak Decay ◽  
Leptonic Decay ◽  
Meson Decay ◽  
Decay Constants ◽  
Pseudoscalar Mesons ◽  
Light Vector ◽  
Decay Widths ◽  
Good Agreement

Leptonic decay widths and leptonic decay constants of light vector mesons and weak leptonic decay widths and weak decay constants of light and heavy pseudoscalar mesons have been studied in a field-theoretic framework based on the independent quark model with a scalar-vector power-law potential. The results are in very good agreement with the experimental data.

scholarly journals The decays τ → (K,K(1460))ντ and the value of the weak decay constants FK and FK′ in the extended NJL model

2019 ◽  
Vol 34 (24) ◽  
pp. 1950137 ◽  
Author(s):  
M. K. Volkov ◽  
K. Nurlan ◽  
A. A. Pivovarov
Keyword(s):  
Excited State ◽  
Axial Vector ◽  
Weak Decay ◽  
Vector Mesons ◽  
Decay Constants ◽  
Njl Model ◽  
Decay Widths ◽  
State Formula

In the extended Nambu–Jona-Lasinio (NJL) model, the decay widths of [Formula: see text], [Formula: see text] are calculated. The contributions from intermediate axial-vector mesons [Formula: see text], [Formula: see text] and the first radially excited state [Formula: see text] are taken into account. Estimates for the weak decay constants [Formula: see text] and [Formula: see text] are given. Predictions are made for the width of [Formula: see text] decay and [Formula: see text] constant.

An independent quark model study of weak leptonic decays of pseudoscalar mesons

2015 ◽  
Vol 30 (16) ◽  
pp. 1550092
Author(s):  
S. N. Jena ◽  
P. K. Nanda ◽  
S. Sahoo ◽  
S. Panda
Keyword(s):  
Experimental Data ◽  
Quark Model ◽  
Decay Constant ◽  
Model Parameters ◽  
Decay Modes ◽  
Leptonic Decays ◽  
Model Study ◽  
Pseudoscalar Mesons ◽  
Model Predictions ◽  
Decay Widths

An independent quark model with a relativistic power-law potential is used to study the weak leptonic decays of light and heavy pseudoscalar mesons. The partial decay width and the decay constant for the weak leptonic decay are derived from the quark–antiquark momentum distribution amplitude which is obtained from the bound quark eigenfunction with the assumption of a strong correlation existing between quark–antiquark momenta inside the decaying meson in its rest frame. The model parameters are first determined from the application of the model to study the ground state hyperfine splitting of ρ, K, D, Ds, B, Bs and Bc mesons. The same model with no adjustable parameters is then used to evaluate the decay constants fM and the decay widths of pseudoscalar mesons. The model predictions agree quite well with the available experimental data as well as with those of several other models. The decay constant for pion and kaon are obtained as fπ = 132 MeV and fk = 161 MeV which closely agree with experimental values. But in case of heavier mesons for which experimental data are not yet available, the present model gives its predictions as fBC > fBS > fB, fDS > fD, fD > fB and fπ > fB which are in conformity with most of other model predictions. The model predictions of the corresponding decay widths and the branching ratios for the [Formula: see text] and [Formula: see text] decay modes are in close agreement with the available experimental data.

scholarly journals Radially excited axial-vector mesons in the extended Nambu–Jona-Lasinio model

2014 ◽  
Vol 29 (24) ◽  
pp. 1450125 ◽  
Author(s):  
A. V. Vishneva ◽  
M. K. Volkov
Keyword(s):  
Experimental Data ◽  
Excited State ◽  
Mass Spectrum ◽  
Excited States ◽  
Axial Vector ◽  
Form Factors ◽  
Radiative Decays ◽  
Vector Mesons ◽  
Polynomial Type ◽  
Quark Momentum

The first radial excitations of axial-vector mesons are considered in the framework of the extended U(3) × U(3) Nambu–Jona-Lasinio model. We calculate the mass spectrum of a1, f1 and also strange axial-vector mesons. For description of radially excited states, we used the form factors of polynomial type of the second order in transverse quark momentum. For the ground- and excited-state mesons consisting of light quarks we have calculated the widths of a number of strong and radiative decays. We got satisfactory agreement with experimental data for the ground states. A set of predictions for the excited states of mesons is given.

Investigating GPDs in the framework of the double distribution model

2016 ◽  
Vol 31 (17) ◽  
pp. 1650091
Author(s):  
F. Nazari ◽  
A. Mirjalili
Keyword(s):  
Experimental Data ◽  
Three Dimensional ◽  
Form Factors ◽  
Deeply Virtual Compton Scattering ◽  
Virtual Compton Scattering ◽  
Distribution Model ◽  
Parton Distributions ◽  
Nucleon Structure Function ◽  
The Difference ◽  
Unpolarized Target

In this paper, we construct the generalized parton distribution (GPD) in terms of the kinematical variables [Formula: see text], [Formula: see text], [Formula: see text], using the double distribution model. By employing these functions, we could extract some quantities which makes it possible to gain a three-dimensional insight into the nucleon structure function at the parton level. The main objective of GPDs is to combine and generalize the concepts of ordinary parton distributions and form factors. They also provide an exclusive framework to describe the nucleons in terms of quarks and gluons. Here, we first calculate, in the Double Distribution model, the GPD based on the usual parton distributions arising from the GRV and CTEQ phenomenological models. Obtaining quarks and gluons angular momenta from the GPD, we would be able to calculate the scattering observables which are related to spin asymmetries of the produced quarkonium. These quantities are represented by [Formula: see text] and [Formula: see text]. We also calculate the Pauli and Dirac form factors in deeply virtual Compton scattering. Finally, in order to compare our results with the existing experimental data, we use the difference of the polarized cross-section for an initial longitudinal leptonic beam and unpolarized target particles [Formula: see text]. In all cases, our obtained results are in good agreement with the available experimental data.

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