Some relativistic aspects of nuclear dynamics at the electrodisintegration of nuclei

TL;DR

This paper develops a relativistic correction approach for nuclear response function calculations in electronuclear reactions, improving agreement with experimental data at higher momentum transfers.

Contribution

It introduces a reference frame method and a relativistic kinematics model to extend non-relativistic calculations' accuracy in nuclear electrodisintegration.

Findings

Agreement with experiment up to 0.4 GeV/c momentum transfer

Reduced disagreement at 0.4 - 1 GeV/c with relativistic corrections

Enhanced accuracy using the new kinematics model and reference frame

Abstract

An approach aimed to extend the applicability range of non-relativistic microscopic calculations of electronuclear response functions is reviewed. In the quasielastic peak region the calculations agree with experiment at momentum transfers up to about 0.4 GeV/c while at higher momentum transfers, in the region about 0.4 - 1 GeV/c, a disagreement is seen. In view of this, to calculate the response functions a reference frame was introduced where dynamics relativistic corrections are small, and the results pertaining to it were transformed exactly to the laboratory reference frame. This proved to remove the major part of the disagreement with experiment. All leading order relativistic corrections to the transition charge operator and to the one--body part of the transition current operator were taken into account in the calculations. Furthermore, a particular model to determine the kinematics inputs of the non-relativistic calculations was suggested. This model provides the correct relativistic relationship between the reaction final-state energy and the momenta of the knocked-out nucleon and the residual system. The above mentioned choice of a reference frame in conjunction with this model has led to an even better agreement with experiment.