Construction of Consistent Meson Exchange Currents by Laplace Transform

We propose a new method for the construction of a consistent meson exchange current in $r$-space for the spin-isospin dependent central and tensor part of phenomenological nucleon-nucleon potentials by using a Laplace transformation, which allows the representation by a finite number of Yukawa functions. This method is applied to the Paris and the recent Argonne $V_{18}$ potentials. Results are presented for electrodisintegration of the deuteron near threshold.Comment: 13 pages Revtex including 9 figures, final version accepted for publication in EPJA (one figure and discussion added

The two-nucleon system in the Δ\Delta region including full meson retardation

A model is developed for the hadronic and electromagnetic interaction in the two-nucleon system above pion threshold in the framework of meson, nucleon and $\Delta$ degrees of freedom. It is based on time-ordered perturbation theory and includes full meson retardation in potentials and exchange currents as well as loop contributions to the nucleonic one-body current. Results for $NN$ scattering and deuteron photodisintegration are presented.Comment: 4 pages Revtex including 2 figures, contribution to "Mesons and Light Nuclei 2001", Prague, July 2-6, 200

Polarization observables in elastic electron deuteron scattering including parity and time reversal violating contributions

The general formalism for polarization observables in elastic electron deuteron scattering is extended to incorporate parity and time reversal violating contributions. Parity violating effects arise from the interference of $\gamma$ and $Z$ exchange as well as from the hadronic sector via a small parity violating component in the deuteron. In addition we have allowed for time reversal invariance violating contributions in the hadronic sector. Formal expressions for the additional structure functions are derived, and their decomposition into the various multipole contributions are given explicitly.Comment: 34 pages Revte

General Multipole Expansion of Polarization Observables in Deuteron Electrodisintegration

Formal expressions are derived for the multipole expansion of the structure functions of a general polarization observable of exclusive electrodisintegration of the deuteron using a longitudinally polarized beam and/or an oriented target. This allows one to exhibit explicitly the angular dependence of the structure functions by expanding them in terms of the small rotation matrices $d^j_{m'm}(\theta)$, whose coefficients are given in terms of the electromagnetic multipole matrix elements. Furthermore, explicit expressions for the coefficients of the angular distributions of the differential cross section including multipoles up to $L_{max}=3$ are listed in tabular form.Comment: 23 pages revtex including one figure, accepted for Eur.Phys. J.

Complete Sets of Polarization Observables in Electromagnetic Deuteron Break-up

For deuteron photo- and electrodisintegration the selection of complete sets of polarization observables is discussed in detail by applying a recently developed new criterion for the check of completeness of a chosen set of observables. The question of ambiguities and their resolution by considering additional observables is discussed for a numerical example, for which the role of experimental uncertainties is also investigated. Furthermore, by inversion of the expressions of the observables as hermitean forms in the $t$-matrix elements a bilinear term of the form $t_{j'}^*t_j$ can be given as a complex linear form in the observables from which an explicit solution for $t_j$ in terms of observables can be obtained. These can also be used to select sets of observables for the explicit representation of the $t$-matrix.Comment: 37 pages revte