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αDecay in extreme laser fields within a deformed Gamow-like model

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Nuclear Science and Techniques 2024年第2期35卷 131-144页

作者： Qiong Xiao Jun-Hao Cheng Yang-Yang Xu You-Tian Zou Jun-Gang Deng Tong-Pu Yu Department of Physics National University of Defense TechnologyChangsha 410073China College of Science China Three Gorges UniversityYichang 443002China

In this study, the effect of extreme laser fields on the α decay process of ground-state even–even nuclei was investigated.Using the deformed Gamow-like model, we found that state-of-the-art lasers can cause a slight change in the α decay penetration probability of most nuclei. In addition, we studied the correlation between the rate of change of the α decay penetration probability and angle between the directions of the laser electric field and α particle emission for different nuclei. Based on this correlation, the average effect of extreme laser fields on the half-life of many nuclei with arbitrary α particle emission angles was calculated. The calculations show that the laser suppression and promotion effects on the α decay penetration probability of the nuclei population with completely random α particle-emission directions are not completely canceled.The remainder led to a change in the average penetration probability of the nuclei. Furthermore, the possibility of achieving a higher average rate of change by altering the spatial shape of the laser is explored. We conclude that circularly polarized lasers may be helpful in future experiments to achieve a more significant average rate of change of the α decay half-life of the nuclei population.

关键词： αDecay Deformed Gamow-like model half-lives Extreme laser field Penetration probability

Systematic study of cluster radioactivity in trans-lead nuclei with various versions of proximity potential formalisms

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Chinese Physics C 2024年第5期48卷 209-225页

作者：刘潇蒋杰栋吴喜军李小华 School of Nuclear Science and Technology University of South ChinaHengyang 421001China School of Math and Physics University of South ChinaHengyang 421001China National Exemplary Base for International Sci&Tech.Collaboration of Nuclear Energy and Nuclear Safety University of South ChinaHengyang 421001China Cooperative Innovation Center for Nuclear Fuel Cycle Technology&Equipment University of South ChinaHengyang 421001China Key Laboratory of Low Dimensional Quantum Structures and Quantum Control Hunan Normal UniversityChangsha 410081China

In this study,based on the framework of the Coulomb and proximity potential model(CPPM),we systematically investigate the cluster radioactivity half-lives of 26 trans-lead nuclei by considering the cluster preformation probability,which possesses a simple mass dependence on the emitted cluster according to R.Blendowske and H.Walliser[Phys.Rev.Lett.61,1930(1988)].Moreover,we investigate 28 different versions of the proximity potential formalisms,which are the most complete known proximity potential formalisms proposed to describe proton radioactivity,two-proton radioactivity,αdecay,heavy-ion radioactivity,quasi-elastic scattering,fusion reactions,and other applications.The calculated results show that the modified forms of proximity potential 1977,denoted as Prox.77-12,and proximity potential 1981,denoted as Prox.81,are the most appropriate proximity potential formalisms for the study of cluster radioactivity,as the root-mean-square deviation between experimental data and relevant theoretical results obtained is the least;both values are 0.681.For comparison,the universal decay law(UDL)proposed by Qi et al.[Phys.Rev.C 80,044326(2009)],unified formula of half-lives forαdecay and cluster radioactivity proposed by Ni et al.[Phys.Rev.C 78,044310(2008)],and scaling law(SL)in cluster radioactivity proposed by Horoi et al.[J.Phys.G 30,945(2004)]are also used.In addition,utilizing CPPM with Prox.77-12,Prox.77-1,Prox.77-2,and Prox.81,we predict the half-lives of 51 potential cluster radioactive candidates whose cluster radioactivity is energetically allowed or observed but not yet quantified in NUBASE2020.The predicted results are in the same order of magnitude as those obtained using the compared semi-empirical and/or empirical formulae.At the same time,the competition betweenαdecay and cluster radioactivity of these predicted nuclei is discussed.By comparing the half-lives,this study reveals thatαdecay predominates.

关键词： cluster radioactivity half-lives Coulomb and proximity potential model

α-particle preformation factors in heavy and superheavy nuclei

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Chinese Physics C 2024年第4期48卷 146-158页

作者：骆松张冬萌亓林静陈勋初鹏程李小华 School of Nuclear Science and Technology University of South ChinaHengyang 421001China School of Mathematics and Physics Qingdao University of Science and TechnologyQingdao 266033China National Exemplary Base for International Sci&Tech.Collaboration of Energy and Nuclear Safety University of South ChinaHengyang 421001China Cooperative Innovation Center for Nuclear Fuel Cycle Technology&Equipment University of South ChinaHengyang 421001China Key Laboratory of Low Dimensional Quantum Structures and Quantum Control Hunan Normal UniversityChangsha 410081China

In this study,α-particle preformation factors in heavy and superheavy nuclei from ^(220)Th to ^(294)Og are investigated.By combing experimental α decay energies and half-lives,the α-particle preformation factors P_(α) are extracted from the ratios between theoretical α decay half-lives calculated using the Two-Potential Approach (TPA)and experimental data.We find that the α-particle preformation factors exhibit a noticeable odd-even staggering behavior,and unpaired nucleons inhibit α-particle preformation.Moreover,we find that both the α decay energy and mass number of parent nucleus exhibit considerable regularity with the extracted experimental α-particle preformation factors.After considering the major physical factors,we propose a local phenomenological formula with only five valid parameters for α-particle preformation factors P_(α).This analytic expression has a clear physical meaning as well as good precision.As an application,this analytic formula is extended to estimate the α-particle preformation factors and further predict the α decay half-lives for unknown even-even nuclei with Z=118 and 120.

关键词： αdecay half-lives preformation factors heavy and superheavy nuclei

Systematic study of proton radioactivity half‑lives

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Nuclear Science and Techniques 2023年第2期34卷 167-177页

作者： Yang‑Yang Xu Xiao‑Yuan Hu De‑Xing Zhu Xi‑Jun Wu Peng‑Cheng Chu Xiao‑Hua Li School of Nuclear Science and Technology University of South ChinaHengyang 421001China School of Math and Physics University of South ChinaHengyang 421001China The Research Center for Theoretical Physics Science SchoolQingdao University of TechnologyQingdao 266033China National Exemplary Base for International Science and Technology.Collaboration of Nuclear Energy and Nuclear Safety University of South ChinaHengyang 421001China Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment University of South ChinaHengyang 421001China Key Laboratory of Low Dimensional Quantum Structures and Quantum Control Hunan Normal UniversityChangsha 410081China

In the present study,on the basis of the screened electrostatic effect of the Coulomb potential,we propose an improved Gamow model within the centrifugal potential in which there are only two adjustable parameters,i.e.,the screened parameters t and g,which represent the combined effect of the interaction potential and reduced mass of the emitted proton-daughter nucleus on the half-life of proton radioactivity in the overlapping region.Using this model,we systematically calculated the proton radioactivity half-lives of 31 spherical nuclei and 13 deformed nuclei and obtained corresponding root-mean-square deviations of 0.274 and 0.367,respectively.The relationship between the proton radioactivity half-life of 177Tlm and the corresponding angular momentum l removed by the emitted proton is also discussed.In addition,we used the proposed model to predict the proton radioactivity half-lives of 18 nuclei whose proton radioactivity is energetically allowed or observed but not yet quantified in NUBASE2020.For comparison,we used the universal decay law of proton radioactivity proposed by Qi et al.(Phys Rev C 85:011303,2012.https://***/10.1103/PhysR evC.85.011303),and the new Geiger–Nuttall law of proton radioactivity proposed by Chen et al.(Eur Phys J 55:214,2019.https://***/10.1140/epja/i2019-12927-7).

关键词： Proton radioactivity Gamow model half-lives

Systematic Calculations of α-Decay half-lives Using Microscopic Deformed Potentials

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Plasma Science and Technology 2012年第7期14卷 588-594页

作者：倪冬冬任中洲 Department of Physics Nanjing University Kavli Institute for Theoretical Physics China Center of Theoretical Nuclear Physics National Laboratory of Heavy-Ion Accelerator

A new version of the generalized density-dependent cluster model （GDDCM） is developed to describe an α particle tunneling through a deformed potential barrier. The microscopic deformed potential is numerically constructed in the double-folding model using the multipole ex- pansion method. The decay width of an α-cluster state is evaluated using the integral of the quasi-bound state wave function, the scattering state wave function, and the difference of poten- tials. We perform a systematic calculation of α-decay half-lives for favored transitions in even-even nuclei ranging from Z=52 to Z=104. The calculated half-lives are in good agreement with the experimental values. The relation between nuclear deformations and α-decay half-lives is also discussed in details.

关键词： a-decay cluster model half-lives deformed potentials

New Geiger-Nuttall law for cluster radioactivity half-lives

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Chinese Physics C 2023年第6期47卷 150-160页

作者：亓林静张冬萌骆松何彪吴喜军陈勋李小华 School of Nuclear Science and Technology University of South ChinaHengyang 421001China College of Physics and Electronics Central South UniversityChangsha 410083China School of Math and Physics University of South ChinaHengyang 421001China Cooperative Innovation Center for Nuclear Fuel Cycle Technology&Equipment University of South ChinaHengyang 421001China National Exemplary Base for International Sci&Tech.Collaboration of Nuclear Energy and Nuclear Safety University of South ChinaHengyang 421001China

In this study,derived from Balasubramaniam’s formula[Phys.Rev.C 70,017301(2004)]and further considering the effect of the parent nucleus mass,blocking effect,and effect of reduced mass on cluster radioactivity half-lives,we propose a new Geiger-Nuttall law that is model-independent to systematically evaluate the halflives of this process for 16 even-even nuclei and 10 odd-A nuclei.For comparison,a single universal curve for cluster radioactivity andαdecay proposed by Poenaru[Phys.Rev.C 83,014601(2011)],a scaling law proposed by Horoi[J.Phys.G:Nucl.Part.Phys.30,945(2004)],an extension of the Viola-Seaborg formula fromαdecay to cluster radioactivity proposed by Ren et al.[Phys.Rev.C 70,034304(2004)],a new semi-empirical formula for exotic cluster decay proposed by Balasubramaniam et al.[Phys.Rev.C 70,017301(2004)],and a unified formula for the half-lives ofαdecay and cluster radioactivity proposed by Ni et al.[Phys.Rev.C 78,044310(2008)]are also used.The calculated results of our new Geiger-Nuttall law are in good agreement with the experimental half-lives,with the least rms being 0.606,and are better than the compared values.Moreover,we extend this formula to predict the cluster radioactivity half-lives of 51 nuclei whose decay energies are energetically allowed or observed but not yet quantified in NUBASE2020.

关键词： cluster radioactivity half-lives Geiger and Nuttall law decay energy

Systematic calculations of cluster radioactivity half-lives in trans-lead nuclei

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Chinese Physics C 2023年第1期47卷 141-150页

作者：亓林静张冬萌骆松李小华吴喜军梁春恬 School of Nuclear Science and Technology University of South ChinaHengyang 421001China School of Math and Physics University of South ChinaHengyang 421001China School of Science Tianjin Chengjian UniversityTianjin 300384China Cooperative Innovation Center for Nuclear Fuel Cyele Technology&Equipment University of South ChinaHengyang 421001China Key Laboratory of Low Dimensional Quantum Structures and Quantum Control Hunan Normal UniversityChangsha 410081China

In the present work,based on the Wentzel-Kramers-Brillouin(WKB)theory,considering the cluster preformation probability(Pc),we systematically investigate the cluster radioactivity half-lives of 22 trans-lead nuclei ranging from221Fr to242Cm.When the mass number of the emitted cluster Achalf-lives of cluster radioactivity have been calculated by the density-dependent cluster model[Phys.Rev.C 70,034304(2004)]and by the unified formula of half-lives for alpha decay and cluster radioactivity[Phys.Rev.C 78,044310(2008)].For comparison,a universal decay law(UDL)proposed by Qi et al.[Phys.Rev.C 80,044326(2009)],a semi-empirical model for bothαdecay and cluster radioactivity proposed by Santhosh[J.Phys.G:Nucl.Part.Phys.35,085102(2008)],and a unified formula of half-lives for alpha decay and cluster radioactivity[Phys.Rev.C 78,044310(2008)]are also used.The calculated results of our work,Ni’s formula,and the UDL can well reproduce the experimental data and are better than those of Santhosh’s model.In addition,we extend this model to predict the half-lives for 51 nuclei,whose cluster radioactivity is energetically allowed or observed but not yet quantified in NUBASE2020.

关键词： cluster radioactivity cluster-formation model(CFM) half-lives preformation probability

Simple model for cluster radioactivity half-lives in trans-lead nuclei

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Chinese Physics C 2023年第11期47卷 68-77页

作者：朱小彦骆松亓林静张冬萌李小华林文斌 School of Nuclear Science and Technology University of South ChinaHengyang 421001China School of Mathematics and Physics University of South ChinaHengyang 421001China Cooperative Innovation Center for Nuclear Fuel Cycle Technology&Equipment University of South ChinaHengyang 421001China National Exemplary Base for International Sci&Tech.Collaboration of Nuclear Energy and Nuclear Safety University of South ChinaHengyang 421001China

In this study,considering the modified preformation probability P_(c)to be log_(10)P_(c)=(A_(c)−1)/3log_(10)P_(α)+c′,where P_(α)and c′are theα-particle preformation probability and an adjustable parameter proposed by Wang et al.[Chin.Phys.C 45,044111(2021)],respectively,we extend a new simple model put forward by Bayrak[J.Phys.G 47,025102(2020)]to systematically study the cluster radioactivity half-lives of 28 trans-lead nuclei ranging from^(222)Fr to^(242)Cm,which is based on the Wentzel-Kramers-Brillouin approximation and Bohr–Sommerfeld quantization condition.For comparison,a universal decay law proposed by Qi et al.[Phys.Rev.C 80,044326(2009)],a three-parameter model-independent formula put forward by Balasubramaniam et al.[Phys.Rev.C 70,017301(2004)],and the semi-empirical model proposed by Tavares et al.[Eur.Phys.J.A 49,1(2013)]are used.Our calculated results reproduce the experimental data well,with a standard deviation of 0.818.Furthermore,we use this model to predict the cluster radioactivity half-lives of 51 possible cluster radioactive candidates whose cluster radioactivities are energetically allowed or observed but not yet quantified in NUBASE2020.

关键词： preformation probability WKB approximation cluster radioactivity half-lives

α-decay half-lives of superheavy nuclei and general predictions

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Chinese Physics C 2009年第8期33卷 633-638页

作者：董建敏张鸿飞王艳召左维苏昕宁李君清 School of Nuclear Science and Technology Lanzhou University Institute of Modern Physics Chinese Academy of Sciences

The generalized liquid drop model （GLDM） and the cluster model have been employed to calculate the α-decay half-lives of superheavy nuclei （SHN） using the experimental α-decay Q values. The results of the cluster model are slightly poorer than those from the GLDM if experimental Q values are used. The prediction powers of these two models with theoretical Q values from Audi et al. （QAudi） and Muntian et al. （QM） have been tested to find that the cluster model with QAudi and QM could provide reliable results for Z 〉 112 but the GLDM with QAudi for Z 112. The half-lives of some still unknown nuclei are predicted by these two models and these results may be useful for future experimental assignment and identification.

关键词： superheavy nuclei α-decay half-lives generalized liquid drop model cluster model