Isospin asymmetry in the pseudospin dynamical symmetry

Pseudospin symmetry in nuclei is investigated considering the Dirac equatio n with a Lorentz structured Woods-Saxon potential. The isospin correlation of the energy splittings of pseudospin partners with the nuclear potential parameters is studied. We show that, in an isotopic chain, the pseudospin s ymmetry is better realized for neutrons than for protons. This behavior com es from balance effects among the central nuclear potential parameters. In general, we found an isospin asymmetry of the nuclear pseudospin interactio n, opposed to the nuclear spin-orbit interaction which is quasi-isospin sym metric.