相关论文: Relativistic Hamiltonian Dynamics and Few-Nucleon …
The momentum distributions of the constituent quarks inside the nucleon and the prominent electroproduced nucleon resonances are investigated in the two most sophisticated, available quark potential models, based respectively on the…
Relativistic effects in the thermodynamical properties of interacting particle systems are investigated within the framework of the relativistic direct interaction theory in various forms of dynamics. In the front form of relativistic…
We have applied the light-front formalism to calculate the electromagnetic form factors for the pion and the kaon from two models at low and high energies in order to explore the differences between such models. We have also compared the…
We develop a complete relativistic theory to describe the dynamics of electronic angular momentum including both spin (S) and orbital (L) contributions in magnetic systems. We start with the relativistic Dirac-Kohn-Sham Hamiltonian under…
The charge and magnetic form factors, FC and FM, of 3He have been extracted in the kinematic range 25 fm-2 < Q2 < 61 fm-2 from elastic electron scattering by detecting 3He recoil nuclei and electrons in coincidence with the High Resolution…
Electromagnetic and Lorentz-scalar form factors are calculated for a bound system of two spin-less particles exchanging a zero-mass scalar particle. Different approaches are considered including solutions of a Bethe-Salpeter equation, a…
We employ a recent approach to the non-relativistic reduction of the electromagnetic current operator in calculations of electronuclear reactions. In contrast to the traditional scheme, where approximations are made for the transferred…
A new approach to the electroweak properties of two--particle composite systems is developed. The approach is based on the use of the instant form of relativistic Hamiltonian dynamics. The main novel feature of this approach is the new…
The Hamiltonian of relativistic particles with electric and magnetic dipole moments that interact with an electromagnetic field is determined in the Foldy-Wouthuysen representation. Transition to the semiclassical approximation is carried…
A parameter-free evaluation of the $N - \Delta$ electromagnetic transition form factors is carried out in a light-front constituent quark model, based on $N$ and $\Delta$ eigenstates of a mass operator which reproduces a large set of hadron…
Extending the concepts of light-front field theory to quantum statistics provides a novel approach towards nuclear matter under extreme conditions. Such conditions exist, e.g., in neutron stars or in the early stage of our universe. They…
We consider relativistic charged particle dynamics and relativistic magnetohydrodynamics using symplectic structures and actions given in terms of co-adjoint orbits of the Poincar\'e group. The particle case is meant to clarify some points…
A short review is given of calculations of the pion electromagnetic and transition form factors within the framework of quantum chromodynamics. It is argued that both the perturbative and nonperturbative aspects of the Q^2 dependence of…
The connection between the Feynman triangle diagram and the light-front formalism for spin-0 and spin-1 two-fermion systems is analyzed. It is shown that in the limit q+ = 0 the form factors for both spin-0 and spin-1 systems can be…
The fomalism is developed to express nucleon matrix elements of the electromagnetic current in terms of form factors consistent with the translational, rotational, and parity symmetries of a cubic lattice. We calculate the number of these…
The electromagnetic form factors of the $\pi$ and the $\rho$ are obtained using the three forms of relativistic kinematics, instant form, point form and (light) front form. Simple representations of the mass operator together with single…
The electromagnetic form factors of light and heavy pseudoscalar mesons are calculated within two covariant constituent-quark models, a light-front and a dispersion relation approach. We investigate the details and physical origins of the…
The analysis of semi-inclusive deep inelastic electron scattering off polarized $^3$He at finite momentum transfers, aimed at the extraction of the quark transverse-momentum distributions in the neutron, requires the use of a distorted…
We consider the forces acting on electrons in magnetic field including the constraints and a condition arising from quantum mechanics. The force is calculated as the electron mass, $m_e$, multiplied by the total time-derivative of the…
Relativistic Hamiltonians are defined as the sum of relativistic one-body kinetic energy, two- and three-body potentials and their boost corrections. In this work we use the variational Monte Carlo method to study two kinds of relativistic…