Magnetic excitations in the nucleon-pair shell model

Yan An Luo, Nankai University
Xiao Bing Zhang, Nankai University
Feng Pan, Liaoning Normal University
Ping Zhi Ning, Nankai University
J. P. Draayer, Louisiana State University


Magnetic transition strengths in 134Ba are discussed within the framework of the nucleon-pair shell model (NPSM) truncated to the SD subspace. The S and D pairs are determined, respectively, by a variational method and a proton-neutron TDA approximation. The M1 and M3 transition strengths are found to be consistent with results from the proton-neutron interacting boson model calculations. The results confirm that the collective magnetic properties of 134Ba are primarily due to the orbital motion of nucleons.