Eur. Phys. J. A (2010) 46: 207-212
https://doi.org/10.1140/epja/i2010-11031-0

Regular Article - Theoretical Physics

Pseudospin symmetry for modified Rosen-Morse potential including a Pekeris-type approximation to the pseudo-centrifugal term

¹ Department of Physics and Electro-Optics Engineering, Xi’an University of Arts and Science, 710065, Xi’an, PRC
² Escuela Superior de Fısica y Matemáticas, Instituto Politécnico Nacional, Edificio 9, Unidad Profesional Adolfo López Mateos, 07738, Mexico D. F., Mexico

Received: 11 May 2010
Accepted: 27 August 2010
Published online: 24 September 2010

Abstract

By applying a Pekeris-type approximation to the pseudo-centrifugal term, we study the pseudospin symmetry of a Dirac nucleon subjected to scalar and vector modified Rosen-Morse (MRM) potentials. A complicated quartic energy equation and spinor wave functions with arbitrary spin-orbit coupling quantum number k are presented. The pseudospin degeneracy is checked numerically. Pseudospin symmetry is discussed theoretically and numerically in the limit case 0 . It is found that the relativistic MRM potential cannot trap a Dirac nucleon in this limit.