Yrast Properties of Dysprosium Isotopes in the Double Mid-Shell Region
ZOU Wen-Hua1,2, GU Jian-Zhong2,3
1School of Nuclear Engineering and Technology, East China Institute of Technology, Fuzhou 3440002China Institute of Atomic Energy, PO Box 275(18), Beijing 1024133Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator of Lanzhou, Lanzhou 730000
Yrast Properties of Dysprosium Isotopes in the Double Mid-Shell Region
ZOU Wen-Hua1,2, GU Jian-Zhong2,3
1School of Nuclear Engineering and Technology, East China Institute of Technology, Fuzhou 3440002China Institute of Atomic Energy, PO Box 275(18), Beijing 1024133Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator of Lanzhou, Lanzhou 730000
摘要The yrast bands of the even-even dysprosium isotopes 164-174Dy are calculated up to high angular momentum 34h based on the projected shell model. Our calculations are in good agreement with the experiments quantitatively. They predict that an energy minimum of the first 2+ state in these isotopes exists around the neutron mid-shell N=104, implying the maximum collectivity in 66170Dy104, however, the energy ratio R4=E(4+1)/E(2+1) reaches a saturation at N=102. Meanwhile, the back-bending plots of these yrast bands are examined carefully. It is found that the sharpness of the back-bending has a gradual shift along the dysprosium isotopic chain, namely, the slope of the back-bending becomes steeper as the neutron number increases except for an irregularity of a decreasing dip angle in the double mid-shell nucleus 170Dy. We suggest that 170Dy undergoes a dual alignment with midshell high-j protons and neutrons aligning simultaneously at spin I≈16h, which probably results in the distinctive back-bending behavior.
Abstract：The yrast bands of the even-even dysprosium isotopes 164-174Dy are calculated up to high angular momentum 34h based on the projected shell model. Our calculations are in good agreement with the experiments quantitatively. They predict that an energy minimum of the first 2+ state in these isotopes exists around the neutron mid-shell N=104, implying the maximum collectivity in 66170Dy104, however, the energy ratio R4=E(4+1)/E(2+1) reaches a saturation at N=102. Meanwhile, the back-bending plots of these yrast bands are examined carefully. It is found that the sharpness of the back-bending has a gradual shift along the dysprosium isotopic chain, namely, the slope of the back-bending becomes steeper as the neutron number increases except for an irregularity of a decreasing dip angle in the double mid-shell nucleus 170Dy. We suggest that 170Dy undergoes a dual alignment with midshell high-j protons and neutrons aligning simultaneously at spin I≈16h, which probably results in the distinctive back-bending behavior.
ZOU Wen-Hua;GU Jian-Zhong;. Yrast Properties of Dysprosium Isotopes in the Double Mid-Shell Region[J]. 中国物理快报, 2010, 27(1): 12101-012101.
ZOU Wen-Hua, GU Jian-Zhong,. Yrast Properties of Dysprosium Isotopes in the Double Mid-Shell Region. Chin. Phys. Lett., 2010, 27(1): 12101-012101.
[1] Casten R F et al 1981 Phys. Rev. Lett. 47 1433 [2] Casten R F 1985 Phys. Lett. B 152 145 [3] Yadav H L, Kaushik M, Jakhar I R and Ansari A 2002 Part. Nucl. Lett. 112 66 [4] Regan P H, Xu F R, Walker P M et al 2002 Phys. Rev.C 65 037302 [5] Rath A K, Stevenson P D, Regan P H et al 2003 Phys.Rev. C 68 044315 [6] Asai M, Ichikawa S, Tsukada K et al 1999 Phys. Rev.C 59 3060 [7] Joss D T et al 2001 Nucl. Phys. A 689 631 [8] S\"{oderstr\"{om P A, Nyberg J, Regan P H et al 2009arXiv:0903.3819v1 [nucl-ex] [9] Hara K, Sun Y 1995 Int. J. Mod. Phys. E 4 637 [10] Hara K, Sun Y 1991 Nucl. Phys. A 529 445 [11] Sun Y, Egido J L 1994 Nucl. Phys. A 580 1 [12] Dufour M and Zuker A P 1996 Phys. Rev. C 541641 [13] Nilsson S G, Tsang C F, Sobiczewski A, Szyman Z et al1969 Nucl. Phys. A 131 1 [14] M\"{oller P et al 1995 At. Data Nucl. Data Tables 59 185 [15] Wu C Y, Simon M W, Cline D and Davis G A 1998 Phys.Rev. C 57 3466 [16] Lalazissis G A, Sharma M M and Ring P 1996 Nucl.Phys. A 597 35 [17] Sun Y, Ring P and Nikkam R S 1991 Z. Phys. A 339 51 [18] Bentsson R, Hamamoto I and Mottelson B R 1978 Phys.Lett. B 73 259 [19] Gruemmer F, Schmid K W and Faessler A 1979 Nucl.Phys. A 326 1
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[15]
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2010, Vol. 27 
