دراسة التحولات الطورية والنقاط الحرجة في منطقة العناصر الارضية النادرة ضمن اطار نموذج البوزونات المتفاعلة IBM - 1 == STUDY OF PHASE TRANSITIONS AND CRITICAL POINTS IN THE REARE EARTH REGION IN THE FRAMEWORK OF INTERACTING BOSOM MODEL (IBM - 1
Author name:
فؤاد عطية مجيد العجيلي
General topic:
Physics
Specific topic:
Physics
Degree:
Doctorate
University:
Al-Nahrain University - College Of Science - Physics Department
Language:
English
University location:
Baghdad
First pages:
26T1705 - p.pdf
Abstract:
A systematic study of isotope chains in the rare - earth region is presented. For the chains 144, , , and 150, energy levels, E2 transition rates, and two - neutron separation energies (SNd15460−Sm16014662−Gd16214864−Dy16666−2n) are described by using the most general (up to two - body terms) IBM - 1 Hamiltonian. For each isotope chain a general fit is performed in such a way that all parameters but one are kept fixed to describe the whole chain.In this region, nuclei evolve from spherical to deformed shapes and a method based on catastrophe theory, in combination with a coherent state analysis to generate the IBM - 1 energy surfaces, is used to identify critical phase transition points.The approach used to fix the Hamiltonian parameters leads to a very good global agreement with the recent available experimental data corresponding to excitation energies, B(E2)’s and S2n values. In particular, an excellent agreement with the measured S2n values is obtained, which is considered a key observable to locate phase transitional regions. The analysis presented here is consistent with previous CQF studies in the same region. As a result we find that 148Nd and 150Sm are the best candidates to be critical, but we should remark that 150Nd and 152Sm are not far away from it.
