https://doi.org/10.1140/epja/i2008-10619-1
Regular Article - Theoretical Physics
Pseudospin symmetry as an accidental symmetry in the relativistic framework
1
Departamento de Física Moderna, Universidad de Cantabria, E-39005, Santander, Spain
2
Departamento de Física Aplicada, Universidad de Cantabria, E-39005, Santander, Spain
3
Department of Physics, St. Petersburg University for Telecommunications, 191065, St. Petersburg, Russia
* e-mail: marcoss@unican.es
Received:
26
April
2008
Revised:
17
June
2008
Published online:
17
July
2008
We analyse the arguments used in the relativistic context to base the quasi-degeneracy of pseudospin doublets (PSDs) observed in atomic nuclei on the smallness of the single-particle central potential (Σ S + Σ0), discussing, especially, the implications of the results obtained in the limit (Σ S + Σ0 = 0. We study also the transition from a relativistic model, where Σ S + Σ0 is a harmonic-oscillator potential and exhibits degenerate PSDs, to a more realistic one with broken pseudospin symmetry. We examine, in particular, the effect of the corresponding pseudospin symmetry-breaking term on the Dirac spinors of the PSDs. An extension of the Nilsson model to the relativistic case is also considered.
PACS: 24.10.Jv Relativistic models – / 21.60.Cs Shell model – / 21.10.Pc Single-particle levels and strength functions – / 24.80.+y Nuclear tests of fundamental interactions and symmetries –
© SIF, Springer-Verlag Berlin Heidelberg, 2008
