Artigo
Optimized δ expansion for the Walecka model
Registro en:
Physics Letters B. Amsterdam: Elsevier B.V., v. 370, n. 1-2, p. 5-11, 1996.
0370-2693
10.1016/0370-2693(95)01578-7
WOS:A1996UA24100002
2-s2.0-0041628970
Autor
Krein, G. [UNESP]
Menezes, D. P.
Pinto, M. B.
Resumen
The optimized δ-expansion is used to study vacuum polarization effects in the Walecka model. The optimized δ-expansion is a nonperturbative approach for field theoretic models which combines the techniques of perturbation theory and the variational principle. Vacuum effects on self-energies and the energy density of nuclear matter are studied up to script O sign(δ2). When exchange diagrams are neglected, the traditional relativistic Hartree approximation (RHA) results are exactly reproduced and, using the same set of parameters that saturate nuclear matter in the RHA, a new stable, tightly bound state at high density is found. Inst. de Fis. Teórica Universidade Estadual Paulista, Rua Pamplona 145, 01405-900 São Paulo, S.P. Departamento de Física Univ. Federal de Santa Catarina, 88.040-900 Florianopolis, S.C. Lab. de Physique Mathématique Université de Montpellier II CNRS-URA 768, 34095 Montpellier Cedex 05 Universidade Estadual Paulista, Instituto de Física Teórica, Teórica, Rua Pamplona 145, 01405-900 São Paulo, S.P.