Sains Malaysiana 51(4)(2022): 1213-1227

http://doi.org/10.17576/jsm-2022-5104-21

The Effect of the Quantization of the Centrifugal Stretching on the Analysis of the Rotational Spectra of Even-Even Nuclei

(Kesan Pengkuantuman Regangan Pengempar terhadap Analisis Spektrum Putaran Nukleus Genap-Genap)

MOHD KH. M. ABU EL SHEIKH¹, ABDURAHIM A. OKHUNOV^2,3,*, HASAN ABU KASSIM¹ & YOON TIEM LEONG⁴

¹Quantum Science Center, Department of Physics, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Federal Territory, Malaysia

²Department of Science in Engineering, Kulliyyah of Engineering, Faculty of Engineering, International Islamic University Malaysia, 50728 Kuala Lumpur, Federal Territory, Malaysia

³Department of Physics, Namangan Institute of Engineering and Technology, 160115 Namangan, Uzbekistan

⁴School of Physics, Universiti Sains Malaysia, 11800 Penang, Malaysia

Received: 7 March 2021/Accepted: 3 September 2021

Abstract

An approach based on the idea that the spinning nucleus being stretched out along the symmetry axis under the influence of some of centrifugal force has been proposed. The stretching in this work is treated within the framework of quantum mechanics rather than classical mechanics which had been used by Diamond Stephens and Swiatecki. Our approach led to a new formula that describes the dependence of the moment of inertia on the angular momentum. This formula is applied for the calculation of rotational ground state bands of even-even nuclei in the atomic mass range  and that having energy ratios in the range between . The results show an overall agreement with the experimental data up to high level energies. There are a small and systematic deviation appears at . This deviation increases with the increasing in  and also differs from one nucleus to another.

Keywords: Bands; energy level; model; properties; rotational; stretching

Abstrak

Pendekatan berdasarkan idea bahawa nukleus berputar yang meregang di sepanjang paksi simetri di bawah pengaruh beberapa daya pengempar telah diusulkan. Peregangan dalam kertas ini dirawat dalam kerangka mekanik kuantum dan bukan mekanik klasik yang telah digunakan oleh Diamond Stephens dan Swiatecki. Pendekatan kami membawa kepada formula baharu yang menunjukkan pergantungan momen inersia pada momentum sudut. Formula ini digunakan untuk pengiraan jalur keadaan asas putaran nukleus genap-genap dalam julat jisim atom  dan mempunyai nisbah tenaga dalam julat antara  . Hasilnya menunjukkan kesepakatan keseluruhan dengan data uji kaji hingga tenaga tahap tinggi. Terdapat penyimpangan kecil dan sistematik yang muncul pada . Penyimpangan ini meningkat dengan peningkatan  dan juga berbeza daripada satu nukleus ke nukleus yang lain.

Kata kunci: Jalur; model; putaran; regangan; tahap tenaga

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^*Corresponding author; email: abdurahimokhun@iium.edu.my