Pair term in the electromagnetic current within the Front-Form dynamics: spin-0 case

Nenhuma Miniatura disponível

Data

2002-09-09

Orientador

Coorientador

Pós-graduação

Curso de graduação

Título da Revista

ISSN da Revista

Título de Volume

Editor

Elsevier B.V.

Tipo

Artigo

Direito de acesso

Acesso restrito

Resumo

The frame and scale dependence of the pair-term contribution to the electromagnetic form factor of a spin-zero composite system of two-fermions is studied within the Light Front. The form factor is evaluated from the plus-component of the current in the Breit frame, using for the first time a nonconstant, symmetric ansatz for the Bethe-Salpeter amplitude. The frame dependence is analyzed by allowing a nonvanishing plus component of the momentum transfer, while the dynamical scale is set by the masses of the constituents and by mass and size of the composite system. A transverse momentum distribution, associated with the Bethe-Salpeter amplitude, is introduced which allows to define strongly and weakly relativistic systems. In particular, for strongly relativistic systems, the pair term vanishes for the Drell-Yan condition, while is dominant for momentum transfer along the light-front direction. For a weakly relativistic system, fitted to the deuteron scale, the pair term is negligible up to momentum transfers of 1 (GeV/c)(2). A comparison with results obtained within the Front-Form Hamiltonian dynamics with a fixed number of constituents is also presented. (C) 2002 Elsevier B.V. B.V. All rights reserved.

Descrição

Palavras-chave

Idioma

Inglês

Como citar

Nuclear Physics A. Amsterdam: Elsevier B.V., v. 707, n. 3-4, p. 399-424, 2002.

Itens relacionados

Financiadores