On the question of spin assignment and quantized alignment in the A~ 100-140 superdeformed mass region

Document Type : Original Article

Author

Physics department - faculty of science- Beni-suef University.

Abstract

The structure of the superdeformed (SD) mass region, A~ 100-140 is re-studied by using a direct approach based on the rotational energy formula E (I, K). To determine the lowest spin (If) and the K-value of the considered SD bands; namely, 104Pd(b1), 132Ce(b1), 134Nd(b1), 136Nd(b2), 142Sm(b1), 148Eu(b1, b2), 131Ce(b1, b2), 133Ce(b1, b2), 133Pr(b1, b3), 137Sm(b1) and 143Eu(b1), we study the dependence of the dynamic, (2) and static, (1) , moments of inertia on the rotational frequency (ℏω). Using a search method, the higher order inertial parameters A and B of such method were determined by fitting the proposed transition energies with their observed ones. The calculated transition energies are strongly dependent on the identified spins. It was found that, when an accurate bandhead spin (I0) is assigned, a good agreement is achieved between the calculated and observed transition energies. The results for the spin are in satisfactory agreement with other theoretical results and available experimental data. A good agreement between the calculated and corresponding experimental transition energies of the SD bands is obtained which supports our methodology. The incremental alignment and also the angular momentum alignment, for the identical SD bands exist among the considered ones, have been studied and the results verified well Stephens’s law of alignment.

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