Validity of the one-body current for the calculation of form factors in the point form of relativistic quantum mechanics

  • B. Desplanques
  • L. Theußl
  • 26 Downloads

Abstract:

Form factors are calculated in the point form of relativistic quantum mechanics for the lowest energy states of a system made of two scalar particles interacting via the exchange of a massless boson. They are compared to the exact results obtained by using solutions of the Bethe-Salpeter equation which are well known in this case (Wick-Cutkosky model). The relevance of the comparison is examined by considering other relativistic quantum-mechanics approaches where results are known or have been obtained recently. Deficiencies of the point-form approach together with the single-particle current are emphasized. They point to quite sizeable contributions of two-body currents. These ones are required to fulfil current conservation in any case and to reproduce the high momentum transfer behaviour expected from the Born amplitude.

PACS. 11.10.St Bound and unstable states; Bethe-Salpeter equations – 11.30.Cp Lorentz and Poincaré invariance – 13.40.Gp Electromagnetic form factors 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© Società Italiana di Fisica and Springer-Verlag 2002

Authors and Affiliations

  • B. Desplanques
    • 1
  • L. Theußl
    • 1
  1. 1.Institut des Sciences Nucléaires (UMR CNRS/IN2P3-UJF), F-38026 Grenoble Cedex, FranceFR

Personalised recommendations