We present a unified model describing electroweak properties of the π and ρ mesons. Using a general method of relativistic parametrization of matrix elements of local operators, adjusted for the nondiagonal in total angular momentum case, we calculate the ρ-meson lepton-decay constant fρ using the same parameters of free constituent quarks that have ensured exclusively good results for the π meson previously. The only free parameter, characterising quark interactions, which include additional spin-spin contribution and hence differ from the π-meson case, is fixed by matching the decay constant to its experimental value. The mean square charge radius is calculated, r 2 ρ = (0.56 ± 0.04) fm 2 . This result verifies, for the ρ-meson case, the conjecture of equality between electromagnetic and strong radii of hadrons tested previously for proton, π and K mesons.
We derive an explicit analytical expression for the magnetic dipole moment of the ρ meson, μ ρ , in a relativistic constituent-quark model. We adopt our relativistic approach to composite systems, modified instant-form (mIF) relativistic quantum mechanics (RQM), that we used particularly to construct a unified π & ρ model [Phys. Rev. D 93, 036007 (2016)] describing electroweak properties of light mesons. This model provides a parameter-free calculation to give μ ρ ¼ 2.16 AE 0.03 ½e/2M ρ which is in accordance with the conventional experimental data. The magnetic, quadrupole, and charge form factors also are derived and presented. We consider the small uncertainty of our value of the magnetic moment as one of the undoubted advantages of the method. A comparison is made with recent lattice QCD results and previous calculations using a variety of methods.
Abstract. Charge and magnetic radii, magnetic and quadrupole moments of the ρ-meson are calculated in framework of the developed by authors version of the instant form of relativistic quantum mechanics with fixed number of particles (IF RQM). The calculations are performed with different wave functions of quarks in the ρ-meson and using the so-called modified impulse approximation (MIA). The electromagnetic characteristics of ρ-meson are obtained without fitting parameters. The value of the magnetic moment coincides with available experimental data: μ ρ = 2.1 ± 0.5 e/2M ρ .
This work is devoted to the description of radiation decays V → Pγ in the framework of Poincareinvariant quantum mechanics (PIKM). A procedure developed for constructing the operator of the electromagnetic current of the transition with different values of the total angular momentum with respect to the conditions of the Lorentz covariance and conservation. As the figures of this approach in a modified relativistic impulse approximation held description of the radiative transition in the instant form PIKM.
The construction of the electromagnetic current operatorRoman Polezhaev
Construction of the operator of the electromagnetic current of the transition to a system of noninteracting particlesIn this paper, we consider the electromagnetic current system of two noninteracting particles.State vector of the one of a free particle in the instant form PIKM can be represented as follows:| p, M, j, m .(2.1)
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.