Multidimensionally constrained relativistic mean-field study of triple-humped barriers in actinides
文献类型：期刊论文
| 作者 | Zhao, J; Lu, BN; Vretenar, D; Zhao, EG ; Zhou, SG
|
| 刊名 | PHYSICAL REVIEW C
 |
| 出版日期 | 2015 |
| 卷号 | 91期号:1页码:14321 |
| 通讯作者 | Zhao, J (reprint author), Chinese Acad Sci, Inst Theoret Phys, State Key Lab Theoret Phys, Beijing 100190, Peoples R China. |
| 英文摘要 | Background: Potential energy surfaces (PES's) of actinide nuclei are characterized by a two-humped barrier structure. At large deformations beyond the second barrier, the occurrence of a third barrier was predicted by macroscopic-microscopic model calculations in the 1970s, but contradictory results were later reported by a number of studies that used different methods. Purpose: Triple-humped barriers in actinide nuclei are investigated in the framework of covariant density functional theory (CDFT). Methods: Calculations are performed using the multidimensionally constrained relativistic mean field (MDC-RMF) model, with the nonlinear point-coupling functional PC-PK1 and the density-dependent meson exchange functional DD-ME2 in the particle-hole channel. Pairing correlations are treated in the BCS approximation with a separable pairing force of finite range. Results: Two-dimensional PES's of Th-226,Th-228,Th-230,Th-232 and U-232,U-234,U-236,U-238 are mapped and the third minima on these surfaces are located. Then one-dimensional potential energy curves along the fission path are analyzed in detail and the energies of the second barrier, the third minimum, and the third barrier are determined. The functional DD-ME2 predicts the occurrence of a third barrier in all Th nuclei and U-238. The third minima in Th-230,Th-232 are very shallow, whereas those in Th-226,Th-228 and U-238 are quite prominent. With the functional PC-PK1 a third barrier is found only in Th-226,Th-228,Th-230. Single-nucleon levels around the Fermi surface are analyzed in Th-226, and it is found that the formation of the third minimum is mainly due to the Z = 90 proton energy gap at beta(20) approximate to 1.5 and beta(30) approximate to 0.7. Conclusions: The possible occurrence of a third barrier on the PES's of actinide nuclei depends on the effective interaction used in multidimensional CDFT calculations. More pronounced minima are predicted by the DD-ME2 functional, as compared to the functional PC-PK1. The depth of the third well in Th isotopes decreases with increasing neutron number. The origin of the third minimum is due to the proton Z = 90 shell gap at relevant deformations. |
| 学科主题 | Physics |
| 类目[WOS] | Physics, Nuclear |
| 关键词[WOS] | GROUND-STATE PROPERTIES ; HARTREE-BOGOLIUBOV THEORY ; FISSION-BARRIERS ; FINITE NUCLEI ; ROTATIONAL BANDS ; TH-232 ; PHOTOFISSION ; THRESHOLD ; EXCITATION ; MODEL |
| 收录类别 | SCI |
| 语种 | 英语 |
| 源URL | [http://ir.itp.ac.cn/handle/311006/21108]  |
| 专题 | 理论物理研究所_理论物理所1978-2010年知识产出 计算平台成果 |
| 推荐引用方式 GB/T 7714 | Zhao, J,Lu, BN,Vretenar, D,et al. Multidimensionally constrained relativistic mean-field study of triple-humped barriers in actinides[J]. PHYSICAL REVIEW C,2015,91(1):14321. |
| APA | Zhao, J,Lu, BN,Vretenar, D,Zhao, EG,&Zhou, SG.(2015).Multidimensionally constrained relativistic mean-field study of triple-humped barriers in actinides.PHYSICAL REVIEW C,91(1),14321. |
| MLA | Zhao, J,et al."Multidimensionally constrained relativistic mean-field study of triple-humped barriers in actinides".PHYSICAL REVIEW C 91.1(2015):14321. |
入库方式： OAI收割
来源：理论物理研究所
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