Deuteron Electromagnetic Form Factors Research Articles

Deuteron electromagnetic form factors and tensor polarization observables in the framework of the hard-wall AdS/QCD model

We study the electromagnetic form factors and tensor polarization observables of the deuteron in the framework of the hard-wall AdS/QCD model. We find a profile function for the bulk twist vector field, which describes the deuteron on the boundary and fix the infrared boundary cut-off of AdS space in accordance with the ground state mass of the deuteron. We obtain the deuteron charge monopole, quadrupole, and magnetic dipole form factors and tensor polarization observables from the bulk Lagrangians for the deuteron and photon field interactions. We plot the momentum transfer dependence of the form factors and tensor polarization observables and compare our numerical results with those in the soft-wall model and experimental data.

Polarization Effects in the Reaction d+eˉ → d+eˉ

The differential cross section and polarization observables for the elastic reaction induced by deuteron scattering off electrons at rest, are calculated in the one-photon-exchange approximation. The following polarization observables were calculated: 1- the analyzing powers (asymmetries) due to the tensor polarization of the deuteron beam, 2 - the spin correlation coefficients caused by the arbitrarily polarized electron target and the vector polarized deuteron beam, 3 - the coefficients of the polarization transfer from the arbitrarily polarized target electron to the recoil electrons. The differential cross section and polarization observables have been expressed in terms of the deuteron electromagnetic form factors: (charge monopole), (magnetic dipole) and (charge quadrupole). Numerical estimations are given for the analyzing powers (asymmetries) due to the tensor polarization of the deuteron beam. They are calculated as functions of the deuteron beam energy for some values of the scattering angle (the angle between the deuteron beam and the recoil electron momenta). For the numerical calculation we use the existing phenomenological parametrization of the deuteron electromagnetic form factors. It turns out that the analyzing powers (asymmetries) are increasing with the growth of the deuteron beam energy and they have appreciable sensitivity to the value of the scattering angle. The specific interest of this reaction is to investigate the possibility to use this reaction for the measurement of the polarization of the high energy deuteron beams.

Covariant spectator theory of np scattering: Deuteron form factors

This paper uses the covariant spectator theory to calculate the deuteron electromagnetic form factors, yielding impressive quantitative results for deuteron observables. Special attention is given to a consistent treatment of currents generated by the nuclear force models obtained from the 2008 high-precision fits to the $N\phantom{\rule{0}{0ex}}N$ scattering data. Noteworthy results are (1) the neutron charge form factor prediction and (2) determination of two off-shell nucleon form factors that contribute to electron-deuteron scattering.

Single and double spin asymmetries in the elastic e-d scattering and their dependence on the deuteron wave function

Single and double spin asymmetries in the elastic electron-deuteron (e-d ) scattering were investigated. The tensor-deuteron asymmetries T2i(i = 0, 1, 2) and the beam-vector-deuteron asymmetries T e 1i(i = 0, 1) were calculated and compared with the available experimental data. The sensitivity of the results for these spin asymmetries to the deuteron wave function has been investigated. The predicted asymmetries were found to be agree with one another and with experiment. It was found that, the double spin asymmetry T e 10 is much smaller than the T e 11-asymmetry. Therefore, in addition to the single tensor-deuteron asymmetry T20, the doubly beam-vector-deuteron asymmetry T e 11 can be used as an another tool for extracting the deuteron electromagnetic form factors.

Deuteron transverse densities in holographic QCD

We investigate the transverse charge density in the longitudinally as well as transversely polarized deuteron using the recent empirical description of the deuteron electromagnetic form factors in the framework of holographic QCD. The predictions of the holographic QCD are compared with the results of a standard phenomenological parameterization. In addition, we evaluate GPDs and the gravitational form factors for the deuteron. The longitudinal momentum densities are also investigated in the transverse plane.

Deuteron electromagnetic form factors with the light-front approach**Supported by National Natural Science Foundation of China (10975146, 11475192), The fund provided by the Sino-German CRC 110 “Symmetries and the Emergence of Structure in QCD" project is also appreciated, YBD thanks FAPESP grant 2011/11973-4 for funding his visit to ICTP-SAIFR

The electromagnetic form factors and low-energy observables of the deuteron are studied with the help of the light-front approach, where the deuteron is regarded as a weakly bound state of a proton and a neutron. Both the S and D wave interacting vertexes among the deuteron, proton, and neutron are taken into account. Moreover, the regularization functions are also introduced. In our calculations, the vertex and the regularization functions are employed to simulate the momentum distribution inside the deuteron. Our numerical results show that the light-front approach can roughly reproduce the deuteron electromagnetic form factors, like charge G0, magnetic G1, and quadrupole G2, in the low Q2 region. The important effect of the D wave vertex on G2 is also addressed.

Deuteron Electromagnetic Form Factors in AdS/QCD

We extend a soft-wall AdS/QCD approach to a description of deuteron properties. Our framework is based an effective action formulated in terms of AdS fields, which are holographically equivalent to the deuteron and photon fields. This action produces the equation of motion for the deuteron wave function and the \(Q^2\)-dependent electromagnetic current, which are then used to calculate the deuteron electromagnetic form factors and structure functions in the Euclidean region. We show that the predicted deuteron quantities are expressed through a universal function, which is defined by a single scale parameter \(\kappa \) and which has the correct \(1/Q^{10}\) power scaling at large \(Q^2\).

Nuclear physics in soft-wall AdS/QCD: Deuteron electromagnetic form factors

We present a high-quality description of the deuteron electromagnetic form factors in a soft-wall AdS/QCD approach. We first propose an effective action describing the dynamics of the deuteron in the presence of an external vector field. Based on this action the deuteron electromagnetic form factors are calculated, displaying the correct 1/Q^10 power scaling for large Q^2 values. This finding is consistent with quark counting rules and the earlier observation that this result holds in confining gauge/gravity duals. The Q^2 dependence of the deuteron form factors is defined by a single and universal scale parameter kappa, which is fixed from data.

Deuteron electromagnetic form factors in transverse plane with a phenomenological Lagrangian approach

A phenomenological Lagrangian approach is employed to study the electromagnetic properties of deuteron. The deuteron is regarded as a loosely bound state of a proton and a neutron. The deuteron electromagnetic form factors are expressed in light-front representation in the transverse plane. The transverse charge density of the deuteron is discussed.

Deuteron electromagnetic form factors in a renormalizable formulation of chiral effective field theory

We calculate the deuteron electromagnetic form factors in a modified version of Weinberg's chiral effective field theory approach to the two-nucleon system. We derive renormalizable integral equations for the deuteron without partial wave decomposition. Deuteron form factors are extracted by applying the Lehmann-Symanzik-Zimmermann reduction formalism to the three-point correlation function of deuteron interpolating fields and the electromagnetic current operator. Numerical results of a leading-order calculation with removed cutoff regularization agree well with experimental data.

Two-photon exchange corrections to the polarizationPyof the deuteron

The corrections of two-photon exchange to the polarization ${P}_{y}$ of the deuteron are studied based on an effective Lagrangian approach. In addition, the two-photon exchange effect on the imaginary part of the deuteron electromagnetic form factors is also discussed.

An estimate of two-photon exchange effect on deuteron electromagnetic form factors

The effect of the two-photon exchange on the deuteron electromagnetic form factors is estimated based on an effective Lagrangian approach. A numerical estimate calculation of the effect is discussed. In particular, the effect on the polarization observables is analyzed.

Estimate of the two-photon exchange effect on deuteron electromagnetic form factors

The corrections of two-photon exchange on deuteron electromagnetic form factors are estimated based on an effective Lagrangian approach. Numerical results for the form factors $G_{C,M,Q}$ of the deuteron with the corrections are compared to its empirical ones. Moreover, the two new form factors, due to the two-photon exchange, are analyzed. Possible way to test the two-photon exchange corrections to the deuteron form factors is discussed.

New method of experimental determination of all three deuteron electromagnetic form factors

By elastic scattering of unpolarized electrons on a polarized deuteron target in the direction of the three momenta of the outgoing deuteron and by measuring the vector polarization of the final deuteron in the same direction and at the same values of squared transferred momenta $t$ as the unpolarized elastic electron-deuteron cross-section is measured, one can find out all three deuteron electromagnetic form factors in the space-like region.

Empirical transverse charge densities in the deuteron

Using the recent empirical information on the deuteron electromagnetic form factors we map out the transverse charge density in the deuteron as viewed from a light front moving towards the deuteron. The charge densities for a transversely polarized deuteron are characterized by monopole, dipole and quadrupole patterns.

Two-photon exchange effect on deuteron electromagnetic form factors

Corrections of two-photon exchange to proton and neutron electromagnetic form factors are employed to study the effect of two-photon exchange on the deuteron electromagnetic form factors. Numerical results of the effect are given. It is suggested to test the effect in the measurement of Pz in a small angle limit.

Phenomenological Lagrangian approach to the electromagnetic deuteron form factors

A phenomenological Lagrangian approach is employed to study the electromagnetic properties of the deuteron. The deuteron is regarded as a weakly bound state of the proton and neutron. We construct a general form for the electromagnetic one- and two-body transition operators formulated in terms of the nucleon fields, which are then used in the calculation of the electromagnetic deuteron form factors. One of the two-body operators is responsible for explaining the quadrupole moment form factor. We show that in our approach the data on the deuteron form factors as well as on the differential cross section of elastic electron-deuteron scattering are well explained.

Asymptotic estimation of some multiple integrals and the electromagnetic deuteron form factors at high momentum transfer

A theorem about asymptotic estimation of multiple integrals of a special type is proved for the case when the integrand peaks at the integration domain boundary, but not at a point of extremum. Using this theorem, the asymptotic expansion of the electromagnetic deuteron form factors at high momentum transfers is obtained in the framework of a two-nucleon model in both the nonrelativistic and relativistic impulse approximations. It is found that the relativistic effects slow down the decrease of deuteron form factors and result in agreement between the relativistic asymptotics and experimental data at high momentum transfers.

Elastic Form Factors of the Proton, Neutron and Deuteron

In this paper an overview of past and future measurements of the elastic nucleon and deuteron electromagnetic form factors and a comparison with a selection of theoretical descriptions is provided.

Model independent analysis of polarization effects in elastic electron–deuteron scattering in presence of two-photon exchange

The general spin structure of the matrix element, for the elastic electron (positron)–deuteron scattering is parametrized using general symmetry properties of the hadron electromagnetic interaction, such as P-, C- and T-invariances as well as lepton helicity conservation in QED at high energy, taking into account the two-photon exchange contribution. The expressions for the differential cross section and for all polarization observables are given in terms of fifteen real functions. In presence of two photon exchange, deuteron electromagnetic form factors can still be extracted from electron and positron elastic scattering in the same kinematical conditions.