Deviation From Rigid Rotational Behavior of Superdeformed Nuclear Bands in Tl and Pb Signature Partners

• Published in: Physics of atomic nuclei 2023-04, Vol.86 (2), p.87-104
• Main Authors: Khalaf, A. M., Taha, M. M., Sirag, M. M.
• Format: Article
• Language: English
• Subjects: Angular momentum; Deviation; Dipoles; Energy; Kinematics; Moments of inertia; Nuclear energy; NUCLEI/Theory; Particle and Nuclear Physics; Perturbation; Physics; Physics and Astronomy; Quadrupoles; Staggering
• ISSN: 1063-7788; 1562-692X
• DOI: 10.1134/S1063778823020102

The model used proposes that the excitation energy expression within a band of an axially symmetric nucleus consists of rotational energy, vibrational energy, and perturbation energy depending on the cubic power of angular momentum. The vibrational and perturbation energies give the deviation from the rigid rotational energy formula. A simulated search program has been written to extract the model parameters and the bandhead spins for eight pairs of signature partners of Tl and Pb odd-mass superdeformed nuclei in order to obtain a minimum mean square deviation between the calculated and the experimental transition energies. The resultant calculated transition energies agree very well with the experimental ones, and the calculated spins agree with the previously assigned spins of other models, which presents responsible support for our model. The role and contribution of excess deviation energy to interaband transition energies were investigated. Rotational frequencies, kinematic and dynamic moments of inertia, and staggering in transition energies between signature partner pairs’ superdeformed bands. To exhibit the energy staggering, two staggering functions have been suggested: The first one represents the difference between the average transition energies and in one band and the transition energy in the signature partner. The second staggering function depends on the dipole transition energies linking the two signature partner bands and quadrupole transition energies within each band. The eight pairs of signature partners show large amplitude staggering.