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Document Type : Research paper


Plasma and Nuclear Physics Research School, Nuclear Science and Technology Research Institute (NSTRI), P.O. Box: 14155-1339, Tehran, Iran


In this paper‎, ‎we study the nature of the dynamics in second-order Quantum Phase Transition (QPT) between vibrational ( ) and -unstable ( ) nuclear shapes‎. ‎Using a transitional Hamiltonian according to an affine SU(1,1) algebra in combination with a coherent state formalism, Shape Phase Transitions (SPT) in odd-nuclei in the framework of the Interacting Boson Fermion Model (IBFM) are investigated‎. ‎Classical analysis reveals a change in the system along with the transition in a critical point‎. ‎The role of a fermion with angular momentum j at the critical point on quantum phase transitions in bosonic systems is investigated via a semi-classical approach‎. ‎The effect of the coupling of the odd particle to an even-even boson core is discussed along with the shape transition and‎, ‎in particular‎, ‎at the critical point‎. Our study confirms the importance of the odd nuclei as necessary signatures to characterize the occurrence of the phase transition and determine the critical point's precise position‎.


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How to cite this article

M. Ghapanvari, A. Kargarian, Investigation of Structure and Nuclear Shape Phase Transition in Odd Nuclei in a multi-j model,

Journal of Nuclear Science and Applications, Vol. 3, No. 2, (2022), P 1-12, Url:                                            ,  DOI:



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