相关论文: Relativistic Hamiltonian Dynamics and Few-Nucleon …
Form factors of a simple system have been calculated in various forms of relativistic quantum mechanics, using a single-particle current. Their comparison has shown large discrepancies. The comparison is extended here to instant- and…
The form factor of hadronic systems in various forms of relativistic quantum mechanics is considered. Motivated by the agreement of the nucleon ``point-form'' results with experiment, results for a toy model corresponding to the simplest…
Photodisintegration and radiative capture in the N2H, N3H, N3He, 2H2H, 2H3He, 2H4He, 3He3H, 4He3H, and 4He3He channels are studied on the basis of the corresponding two-cluster potential models. The astrophysical S factors at low energies…
A manifestly covariant expression for the current matrix elements of three quark bound systems is derived in the framework of the Point Form Relativistic Hamiltonian Dynamics. The relativistic impulse approximation is assumed in the model.…
Elastic electron scattering off $^3$He and $^4$He has recently been studied at forward and backward scattering angles in Hall A at JLab. The results will provide accurate data on the elastic form factors, charge and magnetic for $^3$He and…
Accessing hadronic form factors at large momentum transfers has traditionally presented a challenge for lattice QCD simulations. Here we demonstrate how a novel implementation of the Feynman-Hellmann method can be employed to calculate…
Results for the proton and neutron electric and magnetic form factors as well as the nucleon axial form factor are presented for constituent quark models, based on either one-gluon-exchange and Goldstone-boson-exchange dynamics. The…
The electromagnetic form factors of the $\rho$ meson are evaluated adopting a relativistic constituent quark model based on the light-front formalism, and using a meson wave function with the high-momentum tail generated by the…
Photodisintegration and radiative capture in the N2H, N3H, N3He, 2H2H, 2H3He, 2H4He, 3He3H, 4He3H, and 4He3He channels are studied on the basis of the corresponding two-cluster potential models. The astrophysical S factors at low energies…
We investigate the gravitational form factors of charmonium. Our method is based on a Hamiltonian formalism on the light front known as basis light-front quantization. The charmonium mass spectrum and light-front wave functions were…
Using the point-form approach to relativistic quantum mechanics, a covariant framework is presented for the calculation of proton and neutron electromagnetic form factors. Results for charge radii, magnetic moments, and electric as well as…
Photodisintegration and radiative capture in the N2H, N3H, N3He, 2H2H, 2H3He, 2H4He, 3He3H, 4He3H, and 4He3He channels are studied on the basis of the corresponding two-cluster potential models. The astrophysical S factors at low energies…
We investigate the electromagnetic form factors of the nucleon in the framework of basis light front quantization. We compute the form factors using the light front wavefunctions obtained by diagonalizing the effective Hamiltonian…
We use light-front dynamics to calculate the electromagnetic form-factor for the Hulthen model of the deuteron. For small momentum transfer Q^2 < 5 GeV^2 the relativistic effects are quite small. For Q^2 = 11 GeV^2 there is about a 13%…
We calculate the gravitational form factors (GFFs) and pressure, shear and energy distributions for a quark state dressed with a gluon at one loop in QCD. We use the light-front Hamiltonian approach. In the light-front gauge, we use a…
In this paper, we evaluate the electromagnetic and gravitational form factors as well as the corresponding generalized parton distributions of the electron using the Basis Light-front Quantization approach to QED. We compare our results…
A light-front Hamiltonian reproducing the results of two-dimensional quantum electrodynamics in the Lorentz coordinates is constructed using the bosonization procedure and an analysis of the bosonic perturbation theory in all orders in the…
We construct effective Hamiltonians which despite their apparently nonrelativistic form incorporate relativistic effects by involving parameters which depend on the relevant momentum. For some potentials the corresponding energy eigenvalues…
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 electromagnetic inclusive responses of polarized $^{3}$He and $^{3}$H are thoroughly investigated at the quasielastic peak for squared momentum transfers up to $2 (GeV/c)^2$, within the plane wave impulse approximation. Great emphasys…