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Dynamical nature of the nuclear pseudospin and its isospin asymmetry

R. Lisboa·M. Malheiro·A. Delfino·P. Alberto·M. Fiolhais·M. Chiapparini
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Abstract

Pseudospin symmetry in nuclei is investigated by solving the Dirac equation with Woods-Saxon scalar and vector radial potentials. We relate the pseudospin interaction with a pseudospin-orbit term in a Schroedinger-like equation for the lower component of the Dirac spinor. We show that this term gives a large contribution to the energy splittings of pseudospin partners, so that the near pseudospin degeneracy arises from a significant cancellation among the different terms in that equation. This is a manifestation of the dynamical character of this symmetry in the nucleus. We analyze the isospin dependence of the pseudospin symmetry in a nuclear isotope chain by including a vector-isovector potential V_rho and a Coulomb potential and conclude that V_rho gives the main contribution to the observed pseudospin isospin asymmetry.

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R. Lisboa, M. Malheiro, A. Delfino, P. Alberto, M. Fiolhais, M. Chiapparini. 2002-07-24. Dynamical nature of the nuclear pseudospin and its isospin asymmetry. https://doi.org/10.1142/9789812704429_0025

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