Department of Physics;
Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Education;
and Synergetic Innovation Center for Quantum Effects and Applications;
Hunan Normal University;
Changsha 4100821;
China;
Center for Gravitation and Cosmology;
College of Physical Science and Technology;
Yangzhou University;
Yangzhou 225009;
China;
real spin two-body system; decoupled equation with separable variables forψ_(4)^(B); ffective-one-body theory;