A general non-spherical boson basis is introduced to study the excitation modes in the interacting boson model (IBM). A prescription for construction of intrinsic states is presented. The general IBM Hamiltonian is resolved exactly into intrinsic and collective parts. The limit of large boson number is discussed analytically for spectrum and transitions. The method of analysis reveals an underlying intrinsic and collective structure closely linked with symmetry considerations. The suggested new approach seems to be adequate as a tool to obtain the physical content and normal modes in any number conserving algebraic bosonic system.
Bibliographical noteFunding Information:
This work is based on part of a Ph.D. thesis by the author carried out under the supervision of Professor M. W. Kirson at the Weizmann Institute of Science, Rehovot, Israel. I am deeply grateful to him for his guidance and contributions that led to the shaping of ideas presented here. Professor S. Levit is acknowledged for an instructive quantum many-body course which gave rise to the present work. Stimulating conversations with Professor I. Talmi are much appreciated. I thank Dr. A. Novoselsky for the use of his computer program and Professors A. Arima, F. Iachello, and A. Gelberg for their interest in this work.