作者机构:
[Li, Xiao-Hua; Zhao, Jie-Cheng; Deng, Jun-Gang; Chen, Jiu-Long] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Wu, Xi-Jun] Univ South China, Sch Math & Phys, Hengyang 421001, Peoples R China.;[Li, Xiao-Hua] Univ South China, Cooperat Innovat Ctr Nucl Fuel Cycle Technol & Eq, Hengyang 421001, Peoples R China.;[Li, Xiao-Hua] Hunan Normal Univ, Key Lab Low Dimens Quantum Struct & Quantum Contr, Changsha 410081, Hunan, Peoples R China.
通讯机构:
[Wu, Xi-Jun] U;Univ South China, Sch Math & Phys, Hengyang 421001, Peoples R China.
关键词:
a decay;~(296)Og;hindrance factor;two-potential approach
摘要:
The present work is a continuation of our previous paper [J.-G. Deng, et al., Chin. Phys. C, 41: 124109 (2017)]. In the present work, the a decay half-life of the unknown nucleus 2960g is predicted within the two-potential approach and the hindrance factors of all 20 even-even nuclei in the same region as ~(296)Og, i.e. proton number 82<Z<126 and neutron number 152<N<184, from ~(250)Cm to ~(294)Og, are extracted. The prediction is 1.09 ms within a factor of 5.12. In addition, based on the latest experimental data, a new set of parameters of a decay hindrance factors for the even-even nuclei in this region, considering the shell effect and proton-neutron interaction, are obtained.
摘要:
基于两势方法(two–potential–approach,TPA)系统研究了偶-偶核、奇-A核和奇-奇核α衰变半衰期。为了考虑原子核的壳结构的影响而导致的实验半衰期与计算结果之间的偏差,引入了与α结团形成概率相关的禁戒因子和预形成因子。结合前期相关工作[X. D. Sun et al., Phys. Rev. C 93, 034316 (2016); X. D. Sun et al., Phys. Rev. C 95, 014319 (2017);X. D. Sun et al., Phys. Rev. C 95, 044303 (2017)],考虑到壳效应对α粒子预形成的影响,通过分析α衰变半衰期的实验数据,拟合得到了α粒子预形成因子/禁戒因子修正公式的参数,得到了α衰变预形成因子/禁戒因子的计算结果,证实了壳效应及质子-中子相互作用在α结团形成过程中起着重要的作用,离壳越近预形成概率越小离壳越远预形成概率越大。
摘要:
We study the properties of strange quark matter (SQM) and quark stars (QSs) in strong magnetic fields within the extended confined isospin-density-dependent mass (CIDDM) model including the temperature dependence of the equivalent mass for quarks. The quark symmetry energy, quark symmetry free energy, and the equation of state (EOS) of SQM in constant magnetic fields at finite temperature are investigated, and it is found that including the temperature dependence in CIDDM model and considering strong magnetic fields can both significantly influence the properties of the SQM and the maximum mass of quark stars. Using the density-dependent magnetic field and assuming two extreme cases for the magnetic field orientation in QSs (the radial orientation in which the local magnetic fields are along the radial direction and the transverse orientation in which the local magnetic fields are randomly oriented but perpendicular to the radial orientation), we analyze the mass-radius relations for different stages of the protoquark stars (PQSs) along the star evolution. Our results indicate that the maximum mass of magnetized PQSs may depend on not only the strength distribution and the orientation of the magnetic fields inside the PQSs, but also the heating process and the cooling process in the star evolution.
摘要:
In the present work, we systematically study the α decay preformation factors Pα within the cluster-formation model and α decay half-lives by the proximity potential 1977 formalism for nuclei around Z=82,N=126 closed shells. The calculations show that the realistic Pα is linearly dependent on the product of valance protons (holes) and valance neutrons (holes) NpNn. It is consistent with our previous works [Sun et al., Phys. Rev. C 94, 024338 (2016); Deng et al., Phys. Rev. C 96, 024318 (2017)], in which Pα are model dependent and extracted from the ratios of calculated α half-lives to experimental data. Combining with our previous works, we confirm that the valance proton-neutron interaction plays a key role in the α preformation for nuclei around Z=82,N=126 shell closures whether the Pα is model dependent or microcosmic. In addition, our calculated α decay half-lives by using the proximity potential 1977 formalism taking Pα evaluated by the cluster-formation model can well reproduce the experimental data and significantly reduce the errors.
摘要:
基于两势方法系统地研究了质子数51 Z 83质子放射性核素的衰变半衰期.总的质子–子核相互作用势包括:通过单折叠子核密度和DDM3Y有效相互作用得到的微观核势,通过单折叠子核电荷密度和质子-质子库仑相互作用得到的真实库仑势以及离心势.同时,预测了同一区域16个核的质子放射性半衰期,并且预测的质子放射性半衰期在4.11倍的范围内.此外,还研究了质子放射性的Geiger–Nuttall定律.结果表明,Geiger–Nuttall定律可以用来描述角动量相同的同位素的质子放射性.
作者机构:
[李小华; 赵阶成] School of Nuclear Science and Technology, University of South China, Hengyang, 421001, China;[李小华] Cooperative Innovation Center for Nuclear Fuel Cycle Technology &, Equipment, University of South China, Hengyang, 421001, China;[赵阶成; 陈晓亮; 喻宏; 陈效先] China Institute of Atomic Energy, Beijing, 102413, China
通讯机构:
School of Nuclear Science and Technology, University of South China, Hengyang, China
作者机构:
[Li, Xiao-Hua; Xiang, Dong; Zhao, Jie-Cheng; Deng, Jun-Gang] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Li, Xiao-Hua] Univ South China, Cooperat Innovat Ctr Nucl Fuel Cycle Technol & Eq, Hengyang 421001, Peoples R China.;[Li, Xiao-Hua] Hunan Normal Univ, Key Lab Low Dimens Quantum Struct & Quantum Contr, Changsha 410081, Hunan, Peoples R China.
通讯机构:
[Xiang, Dong] U;Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.
摘要:
In the present work, the unfavored α-decay half-lives and α preformation probabilities of closed-shell nuclei related to ground and isomeric states around Z=82, N=82 and 126 shell closures are investigated by adopting the two-potential approach from the perspective of valence nucleon (hole) and isospin asymmetry of the parent nucleus. The results indicate that α preformation probability has linear dependence on NpNn or NpNnI, the same as the case of favored α decay in our previous work [X.-D. Sun et al., Phys. Rev. C 94, 024338 (2016)]. Np, Nn, and I represent the number of valence protons (holes), the number of valence neutrons (holes), and the isospin of the parent nucleus, respectively. Fitting the α preformation probability data extracted from the differences between experimental data and calculated half-lives without a shell correction, we give two linear formulas of the α preformation probabilities and the values of corresponding parameters. Based on the formulas and corresponding parameters, we calculate the α-decay half-lives for those nuclei. The calculated results can well reproduce the experimental data.
作者机构:
[Guo, Ping; Sun, Xiao-Dong] Univ South China, Sch Math & Phys, Hengyang 421001, Peoples R China.;[Li, Xiao-Hua; Xiang, Dong; Deng, Jun-Gang] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Li, Xiao-Hua] Univ South China, Cooperat Innovat Ctr Nucl Fuel Cycle Technol & Eq, Hengyang 421001, Peoples R China.;[Li, Xiao-Hua] Hunan Normal Univ, Key Lab Low Dimens Quantum Struct & Quantum Contr, Changsha 410081, Hunan, Peoples R China.
通讯机构:
[Xiang, Dong] U;Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.
摘要:
α decay is a common and important process of natural radioactivity of the heavy and superheavy nuclei. From the α decay of nuclei, we can obtain much more information of nuclei structure. In our previous works [X.-D. Sun et al., Phys. Rev. C 93, 034316 (2016); X.-D. Sun et al., Phys. Rev. C 95, 014319 (2017)], we have done systematic study on the α preformation probability of both the even-even and odd- A nuclei within the two-potential approach. The α preformation probabilities will systematically change due to the shell effect, proton-neutron correlation, and so on. This work is the extension of the previous works. In this work, we systematically study the α decay of doubly odd nuclei. We find that for superallowed α decay the α preformation probabilities of doubly odd nuclei are larger than those of odd- A ones in general, and for the heavier nuclei the extra neutrons suppress the proton-neutron correlation resulting in the small α preformation probabilities. The calculated results can well reproduce the experimental half-lives. The half-lives of the α decay chain beginning from nuclide 119296 are also predicted and compared with various empirical formulas.
摘要:
The α decay half-life of the unknown nucleus ~(297)Og is predicted within the two-potential approach, and α preformation probabilities of 64 odd-A nuclei in the region of proton numbers 82<Z< 126 and neutron numbers 152<N<184, from ~(251)Cf to ~(295)Og, are extracted. In addition, based on the latest experimental data, a new set of parameters for α preformation probabilities considering the shell effect and proton-neutron interaction are obtained. The predicted α decay half-life of ~(297)Og is 0.16 ms within a factor of 4.97. The predicted spin and parity of the ground states for ~(269)Sg, ~(285)Fl and ~(293)Lv are 3/2~+,3/2~+ and 5/2~+,respectively.