In this study, based on a two-potential approach, we systematically investigated the proton radioactivity half-lives of spherical proton emitters with 69≤Z≤81 from the ground and/or isomeric state, choosing the nucl...In this study, based on a two-potential approach, we systematically investigated the proton radioactivity half-lives of spherical proton emitters with 69≤Z≤81 from the ground and/or isomeric state, choosing the nuclear potential to be a modified Woods–Saxon potential that contains the isospin effect of the daughter nucleus. It was found that the calculated half-lives could reproduce the experimental data well. Furthermore, we extended this model to predict the half-lives of 17 protonemitting candidates whose radioactivity is energetically allowed or observed but not yet quantified in NUBASE2020. For comparison, the unified fission model, Coulomb potential and proximity potential model, universal decay law for proton emission, and new Geiger–Nuttall law were also used. All the predicted results are consistent with each other.展开更多
In this study,proton emission half-lives were investigated for deformed proton emitters with 53≤Z≤83based on the presented deformed Gamow-like model,where the deformation effect was included in the Coulomb potential...In this study,proton emission half-lives were investigated for deformed proton emitters with 53≤Z≤83based on the presented deformed Gamow-like model,where the deformation effect was included in the Coulomb potential.The experimental half-lives of proton emitters can be reproduced within a factor of 3.45.For comparison,the results from the universal decay law and the new Geiger-Nuttall law are also presented.Furthermore,the relevance of the half-lives to the angular momentum l for ^(117)La,^(121)Pr,^(135)Tb,and ^(141)Ho were analyzed,and the corresponding possible values of l were proposed:l=3,3,4,4.展开更多
In this paper,using theαparticle preformation probabilities Pαfrom Xu et al.[Xu and Ren,Nucl.Phys.A 760,303(2005)],which were extracted by fitting experimental half-lives ofαdecay,based on a phenomenological harmon...In this paper,using theαparticle preformation probabilities Pαfrom Xu et al.[Xu and Ren,Nucl.Phys.A 760,303(2005)],which were extracted by fitting experimental half-lives ofαdecay,based on a phenomenological harmonic oscillator potential model(HOPM)[Bayrak,J Phys G 47,025102(2020)],refitting 178αdecay half-lives of even-even nuclei obtained from the latest nuclear property table NUBASE2020,we obtain the only one adjustable parameter V0-162.6 MeV in the HOPM,i.e.,the depth of nuclear potential.The corresponding root-mean-square(rms)deviation isσ-0.322.Furthermore,to consider the contribution of centrifugal potential to unfavoredαdecay half-lives,adding a new term■(d and l are the adjustable parameter and orbital angular momentum carried away by emittedαparticle)to the logarithmic form of favoredαdecay half-lives under the HOPM framework,we propose an improved simple model(ISM)for calculating favored and unfavoredαdecay half-lives.Fitting the experimental half-lives of 205 unfavoredαdecay,we obtain d-0.381.The ISM is used to calculate the unfavoredαdecay half-lives of 128 odd-A and 77 odd-odd nuclei.The results improve by 54.2%and 53.6%,respectively,compared with HOPM.In addition,we extend the ISM to predict theαdecay half-lives of 144 nuclei with Z=117,118,119,and 120.For comparison,the improved model with eight parameters(DUR)proposed by Deng et al.[Deng,Phys.Rev.C 101,034307(2020)]and the modified universal decay law(MUDL)proposed by Soylu et al.[Soylu,Nucl.Phys.A 1013,122221(2021)]are also used.The predictions of these models and/or formulas are generally consistent with each other.展开更多
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_...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.展开更多
In this work,considering the preformation factor of the emitted two protons in parent nucleus S_(2p) and the effect of the parent nucleus deformation,based on the Wentzel-Kramers-Brillouin approximation and Bohr-Somme...In this work,considering the preformation factor of the emitted two protons in parent nucleus S_(2p) and the effect of the parent nucleus deformation,based on the Wentzel-Kramers-Brillouin approximation and Bohr-Sommerfeld quantization condition,we improve a simple phenomenological model proposed by Bayrak[J.Phys.G:47,025102(2020)]to systematically study 2p radioactivity half-lives.This model contains two adjustable parameters V_(0) and a_(β),which are related to the depth of nuclear potential and effect of deformation.The calculated results show that this model can effectively reproduce the experimental data with a corresponding root-mean-square(RMS)standard deviation of σ=0.683.For comparison,we include the Gamow-like model(GLM)proposed by Liu et al.[Chin.Phys.C 45,044110(2021)],generalized liquid drop model(GLDM)proposed by Cui et al.[Phys.Rev.C 101,014301(2020)],effective liquid drop model(ELDM)proposed by M.Gonalves et al.[Phys.Lett.B 774,14(2017)],two-potential approach with Skyrme-Hartree-Fock(TPASHF)proposed by Pan et al.[Chin.Phys.C 45,124104(2021)],phenomenological model with a screened electrostatic barrier(SEB)propoesed by Zou et al.[Chin.Phys.C 45,104101(2021)],unified fission model(UFM)proposed by Xing et al.[Chin.Phys.C 45,124105(2021)],Coulomb and proximity potential model for deformed nuclei(CPPMDN)proposed by Santhosh[Phys.Rev.C 104,064613(2021)],two-parameter empirical formula proposed by Liu et al.[Chin.Phys.C 45,024108(2021)],and four-parameter empirical formula proposed by Sreeja et al.[Eur.Phys.J.A 55,33(2019)].In addition,we use this model to 2p predict the radioactive half-lives of some possible potential nuclei whose 2p radioactivity are energetically allowed or observed but not yet quantified in NUBASE2020.展开更多
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 preformatio...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.展开更多
In this study,we systematically investigate theαdecay preformation factors,Pα,and theαdecay half-lives of 152 nuclei around Z=82,N=126 closed shells based on the generalized liquid drop model(GLDM)with Pαbeing ext...In this study,we systematically investigate theαdecay preformation factors,Pα,and theαdecay half-lives of 152 nuclei around Z=82,N=126 closed shells based on the generalized liquid drop model(GLDM)with Pαbeing extracted from the ratio of the calculatedαdecay half-life to the experimental one.The results show that there is a remarkable linear relationship between Pαand the product of valance protons(holes)Np and valance neutrons(holes)Nn.At the same time,we extract theαdecay preformation factor values of the even–even nuclei around the Z=82,N=126 closed shells from the study of Sun et al.[J.Phys.G:Nucl.Part.Phys.,45:075106(2018)],in which theαdecay was calculated by two different microscopic formulas.We find that theαdecay preformation factors are also related to NpNn.Combining with our previous studies[Sun et al.,Phys.Rev.C,94:024338(2016);Deng et al.,ibid.96:024318(2017);Deng et al.,ibid.97:044322(2018)]and that of Seif et al.,[Phys.Rev.C,84:064608(2011)],we suspect that this phenomenon of linear relationship for the nuclei around the above closed shells is model-independent.This may be caused by the effect of the valence protons(holes)and valence neutrons(holes)around the shell closures.Finally,using the formula obtained by fitting theαdecay preformation factor data calculated by the GLDM,we calculate theαdecay half-lives of these nuclei.The calculated results agree with the experimental data well.展开更多
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 propose...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.展开更多
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-l...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.展开更多
In this work,we systematically study theαdecay half-lives of 196 even–even nuclei using a two-potential approach improved by considering nuclear deformation.The results show that the accuracy of this model has been ...In this work,we systematically study theαdecay half-lives of 196 even–even nuclei using a two-potential approach improved by considering nuclear deformation.The results show that the accuracy of this model has been improved after considering nuclear deformation.In addition,we extend this model to predict theαdecay half-lives of Z=118 and 120 isotopes by inputting theαdecay energies extracted from the Weizsacker–Skyrme-type(WS-type)mass model,a simple nuclear mass formula,relativistic continuum Hartree–Bogoliubov theory and Duflo-Zuker-19(DZ19)mass model.It is useful for identifying the new superheavy elements or isotopes for future experiments.Finally,the predictedαdecay energies and half-lives of Z=118 and 120isotopes are analyzed,and the shell structure of superheavy nuclei is discussed.It shows that the shell effect is obvious at N=184,while the shell effect at N=178 depends on the nuclear mass model.展开更多
In this study,we systematically investigate the proton radioactivity half-lives of 33 spherical nuclei based on the relationship between Skyrme parameters and the macroscopic quantities of nuclear matter.Using the two...In this study,we systematically investigate the proton radioactivity half-lives of 33 spherical nuclei based on the relationship between Skyrme parameters and the macroscopic quantities of nuclear matter.Using the two-potential approach with the spherical Skyrme-Hartree-Fock model,the correlation between proton radioactivity half-life and the macroscopic quantities is analyzed.Moreover,we obtain a new Skyrme parameter set by fitting the two most weighted macroscopic quantities.Compared with the Skyrme parameters MSLO and the theoretical model of proton radioactivity UDLP,the theoretical proton radioactivity half-life calculated using the new Skyrme parameter set can better reproduce the experimental data.展开更多
In the present work,a two-parameter empirical formula is proposed,based on the Geiger-Nuttall law,to study two-proton( 2p )radioactivity.Using this formula,the calculated 2p radioactivity half-lives are in good agreem...In the present work,a two-parameter empirical formula is proposed,based on the Geiger-Nuttall law,to study two-proton( 2p )radioactivity.Using this formula,the calculated 2p radioactivity half-lives are in good agreement with the experimental data as well as with calculated results obtained by Goncalves et al.[Phys.Lett.B 774,14(2017)]using the effective liquid drop model(ELDM),Sreeja et al.[Eur.Phys.J.A 55,33(2019)]using a four-parameter empirical formula,and Cui et al.[Phys.Rev.C 101:014301(2020)]using a generalized liquid drop model(GLDM).In addition,this two-parameter empirical formula is extended to predict the half-lives of 22 possible 2p radioactivity candidates with 2p radioactivity released energy Q_(2p)>0 ,obtained from the latest evaluated atomic mass table AME2016.The predicted results are highly consistent with those obtained using other theoretical models such as the ELDM,GLDM and four-parameter empirical formula.展开更多
In this work,based on the liquid-drop model and considering the shell correction,we propose a simple formula to calculate the released energy of proton radioactivity(Q_(p)).The parameters of this formula are obtained ...In this work,based on the liquid-drop model and considering the shell correction,we propose a simple formula to calculate the released energy of proton radioactivity(Q_(p)).The parameters of this formula are obtained by fitting the experimental data of 29 nuclei with proton radioactivity from ground state.The standard deviation between the theoretical values and experimental ones is only 0.157 Me V.In addition,we extend this formula to calculate 51 proton radioactivity candidates in region 51≤Z≤83 taken from the latest evaluated atomic mass table AME2016 and compared with the Q_(p)calculated by WS4 and HFB-29.The calculated results indicate that the evaluation ability of this formula for Q_(p)is inferior to WS4 while better than HFB-29.展开更多
Based on the liquid-drop model and using the first derivative of the normalized Gaussian function to consider the shell correction,a simpleα-decay energy formula is proposed for heavy and superheavy nuclei.The values...Based on the liquid-drop model and using the first derivative of the normalized Gaussian function to consider the shell correction,a simpleα-decay energy formula is proposed for heavy and superheavy nuclei.The values of corresponding adjustable parameters are obtained by fittingα-decay energies of 209 nuclei ranging from Z=90 to Z=118 with N≥140.The calculated results are in good agreement with the experimental data.The average and standard deviations between the experimental data and theoretical results are 0.141 and 0.190 Me V,respectively.For comparison,the reliable formulae proposed by Dong T K et al(2010,Phys.Rev.C 82,034320),Dong J M et al(2010,Phys.Rev.C 81,064309)and the WS3+nuclear mass model proposed by Wang N et al(2011,Phys.Rev.C 84,051303)are also used.The results indicate that our improved 7-parameter formula is superior to these empirical formulae and is largely consistent with the WS3+nuclear mass model.In addition,we extend this formula to predict theα-decay energies for nuclei with Z=117,118,119 and 120.The predicted results of these formulae are basically consistent.展开更多
In the present work,we predict the α decay half-lives of unknown even-even nuclei 296-308120 within the two-potential approach,whose α decay energy Qa is calculated using WS3+mass model.To reduce the deviations betw...In the present work,we predict the α decay half-lives of unknown even-even nuclei 296-308120 within the two-potential approach,whose α decay energy Qa is calculated using WS3+mass model.To reduce the deviations between the predictions and experimental data due to nuclear shell effect,the analytic formula of α decay hindrance factor is introduced to the two-potential approach,whose parameters had been extracted from even-even nuclei in the region of 82 <Z <126 and 152 <N ≤184 in our previous work [Deng et al.,Chin.Phys.C 42(2018) 044102].In addition,for comparing,we use a type of α decay general formula Universal Decay Law(UDL) and a semi-empirical formula in the superheavy nucleus(SEMFLS) to calculate the half-lives of even-even nuclei 296-308120.The results indicate that our predicted values and the calculated values of the above two empirical formulas are mutually confirmed.Meanwhile,we systematically study α decay chains of 296-308120 and predict the decay modes for superheavy nuclei to help to identify new superheavy isotopes.展开更多
In this study,a phenomenological model is proposed based on Wentzel-Kramers-Brillouin(WKB)theory and applied to investigate the two-proton(2p)radioactive half-lives of nuclei near or beyond the proton drip line.The to...In this study,a phenomenological model is proposed based on Wentzel-Kramers-Brillouin(WKB)theory and applied to investigate the two-proton(2p)radioactive half-lives of nuclei near or beyond the proton drip line.The total diproton-daughter nucleus interaction potential is composed of the Hulthen-type electrostatic term and the centrifugal term.The calculated 2p radioactive half-lives can accurately reproduce the existing 10 experimental datasets of five true 2p radioactive nuclei withσ=0.736.In addition,we extend this model to predict the half-lives of possible 2p radioactive nuclei whose 2p radioactivity is energetically allowed or observed but not yet quantified in NUBASE2016.The predicted results are in agreement with those obtained using the Gamow-like model,generalized liquid drop model,Sreeja formula,and Liu formula.展开更多
In the present work,we systematically study the α-decay half-lives of uranium(Z=92) isotopes based on the Gamow model with a screened electrostatic barrier.There are only two adjustable parameters in our model i.e.th...In the present work,we systematically study the α-decay half-lives of uranium(Z=92) isotopes based on the Gamow model with a screened electrostatic barrier.There are only two adjustable parameters in our model i.e.the parameter g and the screening parameter t in the Hulthen potential for considering the screened electrostatic effect of the Coulomb potential.The calculated results are in good agreement with experimental data,and the corresponding root-mean-square(rms) deviations of uranium isotopes with α transition orbital angular momentum l=0 and l=2 are 0.141 and 0.340,respectively.Moreover,we extend this model to predict α-decay half-lives of uranium isotopes whose a decay is energetically allowed or observed but not yet quantified in NUBASE2020.For comparison,the modified Hatsukawa formula(XLZ),the unified Royer formula(DZR),the universal decay law(UDL) and the Viola-Seaborg-Sobiczewski formula(VSS) are also used.The predictions are basically consistent with each other.Meanwhile,the results also indicate that N=126 shell closure is still robust at Z=92 and the spectroscopic factor S_(α) is almost the same for uranium isotopes with the same l.展开更多
In the present work,a phenomenological one-parameter model(OPM)based on the WentzelKramers-Brillouin(WKB)theory is applied to study the favored one proton radioactivity(the orbital angular momentum l taken away by the...In the present work,a phenomenological one-parameter model(OPM)based on the WentzelKramers-Brillouin(WKB)theory is applied to study the favored one proton radioactivity(the orbital angular momentum l taken away by the emitted proton is equal to zero)half-lives.The calculated results can reproduce the experimental data well within a factor of~3.In addition,we extend the OPM to predict the half-lives of possible favored one proton radioactivity nuclei whose decay is energetically allowed or observed but not quantified in NUBASE2020.For comparison,a universal decay law of one proton radioactivity(UDLP)is also used.It is obviously found that our predicted results are close to the ones using UDLP.The predictions are helpful for searching for the new nuclides with favored one proton radioactivity.展开更多
In this study,based on Wentzel-Kramers-Brillouin theory,we systematically investigate the cluster radioactivity half-lives of 22 nuclei ranging from^(221)Fr to^(242)Cm using a phenomenological model that considers the...In this study,based on Wentzel-Kramers-Brillouin theory,we systematically investigate the cluster radioactivity half-lives of 22 nuclei ranging from^(221)Fr to^(242)Cm using a phenomenological model that considers the screened electrostatic effect of the Coulomb potential.In this model,there are two adjustable parameters,t and g,which are related to the screened electrostatic barrier and the strength of the spectroscopic factor,respectively.The calculated results indicate that this model can effectively reproduce the experimental data,with a corresponding rootmean-square deviation of 0.660.In addition,we extend this model to predict the half-lives of possible cluster radioactive candidates whose cluster radioactivities are energetically allowed or observed but not yet quantified in the evaluated nuclear properties table NUBASE2020.The predicted results are consistent with those obtained using other theoretical models and/or empirical formulas,including the universal decay law proposed by Qi et al.[Phys.Rev.C 80,044326(2009)],a semi-empirical model for bothαdecay and cluster radioactivity proposed by Santhosh et al.[J.Phys.G 35,085102(2008)],and a unified formula for the half-lives ofαdecay and cluster radioactivity proposed by Ni et al.[Phys.Rev.C 78,044310(2008)].展开更多
Considering the preformation probability of the two emitted protons in the parent nucleus,we extend the Coulomb and proximity potential model(CPPM)to systematically study two-proton(2p)radioactivity half-lives of the ...Considering the preformation probability of the two emitted protons in the parent nucleus,we extend the Coulomb and proximity potential model(CPPM)to systematically study two-proton(2p)radioactivity half-lives of the nuclei close to proton drip line.The proximity potential chosen is Prox.81 proposed by Blocki et al.in 1981.Furthermore,we apply this model to predict the half-lives of possible 2p radioactive candidates whose 2p radioactivity is energetically allowed or observed but not yet quantified in the evaluated nuclear properties table NUBASE2016.The predicted results are in good agreement with those from other theoretical models and empirical formulas,namely the effective liquid drop model(ELDM),generalized liquid drop model(GLDM),Gamow-like model,Sreeja formula and Liu formula.展开更多
基金supported in part by the National Natural Science Foundation of China(Nos. 12175100 and 11975132)the Construct Program of the Key Discipline in Hunan Province+4 种基金the Research Foundation of Education Bureau of Hunan Province,China(Nos. 21B0402 and 18A237)the Natural Science Foundation of Hunan Province, China(No. 2018JJ2321)the Innovation Group of Nuclear and Particle Physics in USC, the Shandong Province Natural Science Foundation, China(No. ZR2022JQ04)the Hunan Provincial Innovation Foundation for Postgraduates(No.CX20220993)the Opening Project of Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment,University of South China(No. 2019KFZ10)。
文摘In this study, based on a two-potential approach, we systematically investigated the proton radioactivity half-lives of spherical proton emitters with 69≤Z≤81 from the ground and/or isomeric state, choosing the nuclear potential to be a modified Woods–Saxon potential that contains the isospin effect of the daughter nucleus. It was found that the calculated half-lives could reproduce the experimental data well. Furthermore, we extended this model to predict the half-lives of 17 protonemitting candidates whose radioactivity is energetically allowed or observed but not yet quantified in NUBASE2020. For comparison, the unified fission model, Coulomb potential and proximity potential model, universal decay law for proton emission, and new Geiger–Nuttall law were also used. All the predicted results are consistent with each other.
基金Supported in part by the National Natural Science Foundation of China (12175100, 11975132)the Construct Program of the Key Discipline in Hunan Province+5 种基金the Research Foundation of Education Bureau of Hunan Province,China (21B0402, 18A237)the Natural Science Foundation of Hunan Province,China (2018JJ2321)the Innovation Group of Nuclear and Particle Physics in USCthe Shandong Province Natural Science Foundation,China (ZR2022JQ04)the Hunan Provincial Innovation Foundation For Postgraduate (CX20220993)the Opening Project of Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment,University of South China (2019KFZ10).
文摘In this study,proton emission half-lives were investigated for deformed proton emitters with 53≤Z≤83based on the presented deformed Gamow-like model,where the deformation effect was included in the Coulomb potential.The experimental half-lives of proton emitters can be reproduced within a factor of 3.45.For comparison,the results from the universal decay law and the new Geiger-Nuttall law are also presented.Furthermore,the relevance of the half-lives to the angular momentum l for ^(117)La,^(121)Pr,^(135)Tb,and ^(141)Ho were analyzed,and the corresponding possible values of l were proposed:l=3,3,4,4.
基金Supported in part by the National Natural Science Foundation of China(12175100,11975132)the Construct Program of the Key Discipline in Hunan Province,the Research Foundation of Education Bureau of Hunan Province,China(22A0305,21B0402)+1 种基金the Natural Science Foundation of Hunan Province,China(2018JJ2321)the Innovation Group of Nuclear and Particle Physics in USC the Hunan Provincial Innovation Foundation for Postgraduate(CX20230962)。
文摘In this paper,using theαparticle preformation probabilities Pαfrom Xu et al.[Xu and Ren,Nucl.Phys.A 760,303(2005)],which were extracted by fitting experimental half-lives ofαdecay,based on a phenomenological harmonic oscillator potential model(HOPM)[Bayrak,J Phys G 47,025102(2020)],refitting 178αdecay half-lives of even-even nuclei obtained from the latest nuclear property table NUBASE2020,we obtain the only one adjustable parameter V0-162.6 MeV in the HOPM,i.e.,the depth of nuclear potential.The corresponding root-mean-square(rms)deviation isσ-0.322.Furthermore,to consider the contribution of centrifugal potential to unfavoredαdecay half-lives,adding a new term■(d and l are the adjustable parameter and orbital angular momentum carried away by emittedαparticle)to the logarithmic form of favoredαdecay half-lives under the HOPM framework,we propose an improved simple model(ISM)for calculating favored and unfavoredαdecay half-lives.Fitting the experimental half-lives of 205 unfavoredαdecay,we obtain d-0.381.The ISM is used to calculate the unfavoredαdecay half-lives of 128 odd-A and 77 odd-odd nuclei.The results improve by 54.2%and 53.6%,respectively,compared with HOPM.In addition,we extend the ISM to predict theαdecay half-lives of 144 nuclei with Z=117,118,119,and 120.For comparison,the improved model with eight parameters(DUR)proposed by Deng et al.[Deng,Phys.Rev.C 101,034307(2020)]and the modified universal decay law(MUDL)proposed by Soylu et al.[Soylu,Nucl.Phys.A 1013,122221(2021)]are also used.The predictions of these models and/or formulas are generally consistent with each other.
基金Supported in part by the National Natural Science Foundation of China (12175100, 11975132)the Construct Program of the Key Discipline in Hunan Province+5 种基金the Research Foundation of Education Bureau of Hunan Province,China (21B0402, 18A237, 22A0305)the Natural Science Foundation of Hunan Province,China(2018JJ2321)the Innovation Group of Nuclear and Particle Physics in USCthe Shandong Province Natural Science Foundation,China (ZR2022JQ04)the Opening Project of Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment,University of South China (2019KFZ10)Hunan Provincial Innovation Foundation for Postgraduate (CX20230962).
文摘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.
基金Supported in part by the National Natural Science Foundation of China(12175100,11975132)the Construct Program of the Key Discipline in Hunan Province,the Research Foundation of Education Bureau of Hunan Province,China(21B0402,18A237)+3 种基金the Natural Science Foundation of Hunan Province,China(2018JJ2321)the Innovation Group of Nuclear and Particle Physics in USC,the Natural Science Foundation of Shandong Province,China(ZR2022JQ04)the Innovation Foundation For Postgraduate of Hunan Province,China(CX20220993)the Opening Project of Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment,University of South China(2019KFZ10)。
文摘In this work,considering the preformation factor of the emitted two protons in parent nucleus S_(2p) and the effect of the parent nucleus deformation,based on the Wentzel-Kramers-Brillouin approximation and Bohr-Sommerfeld quantization condition,we improve a simple phenomenological model proposed by Bayrak[J.Phys.G:47,025102(2020)]to systematically study 2p radioactivity half-lives.This model contains two adjustable parameters V_(0) and a_(β),which are related to the depth of nuclear potential and effect of deformation.The calculated results show that this model can effectively reproduce the experimental data with a corresponding root-mean-square(RMS)standard deviation of σ=0.683.For comparison,we include the Gamow-like model(GLM)proposed by Liu et al.[Chin.Phys.C 45,044110(2021)],generalized liquid drop model(GLDM)proposed by Cui et al.[Phys.Rev.C 101,014301(2020)],effective liquid drop model(ELDM)proposed by M.Gonalves et al.[Phys.Lett.B 774,14(2017)],two-potential approach with Skyrme-Hartree-Fock(TPASHF)proposed by Pan et al.[Chin.Phys.C 45,124104(2021)],phenomenological model with a screened electrostatic barrier(SEB)propoesed by Zou et al.[Chin.Phys.C 45,104101(2021)],unified fission model(UFM)proposed by Xing et al.[Chin.Phys.C 45,124105(2021)],Coulomb and proximity potential model for deformed nuclei(CPPMDN)proposed by Santhosh[Phys.Rev.C 104,064613(2021)],two-parameter empirical formula proposed by Liu et al.[Chin.Phys.C 45,024108(2021)],and four-parameter empirical formula proposed by Sreeja et al.[Eur.Phys.J.A 55,33(2019)].In addition,we use this model to 2p predict the radioactive half-lives of some possible potential nuclei whose 2p radioactivity are energetically allowed or observed but not yet quantified in NUBASE2020.
基金Supported in part by the National Natural Science Foundation of China(12175100,11975132)the construct program of the key discipline in Hunan province,the Research Foundation of Education Bureau of Hunan Province,China(18A237,22A0305)+4 种基金Hunan Provincial Department of Education Scientific Research Project(19A440)the Shandong Province Natural Science Foundation,China(ZR2022JQ04)the Opening Project of Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment,University of South China(2019KFZ10)the Innovation Group of Nuclear and Particle Physics in USC,Hunan Provincial Innovation Foundation for Postgraduate(CX20230962)Science and technology plan project of Hengyang City(202150063428).
文摘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.
基金Supported in part by the National Natural Science Foundation of China(11205083,11505100,11705055)the Construct Program of the Key Discipline in Hunan Province,the Research Foundation of Education Bureau of Hunan Province,China(15A159,18A237)+4 种基金the Natural Science Foundation of Hunan Province,China(2015JJ3103,2015JJ2121,2018JJ3324)the Innovation Group of Nuclear and Particle Physics in USC,the Shandong Province Natural Science Foundation,China(ZR2015AQ007)the Hunan Provincial Innovation Foundation For Postgraduate(CX20190714,CX20200909)the National Innovation Training Foundation of China(201910555161)and the Opening Project of Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment,University of South China(2019KFZ10)。
文摘In this study,we systematically investigate theαdecay preformation factors,Pα,and theαdecay half-lives of 152 nuclei around Z=82,N=126 closed shells based on the generalized liquid drop model(GLDM)with Pαbeing extracted from the ratio of the calculatedαdecay half-life to the experimental one.The results show that there is a remarkable linear relationship between Pαand the product of valance protons(holes)Np and valance neutrons(holes)Nn.At the same time,we extract theαdecay preformation factor values of the even–even nuclei around the Z=82,N=126 closed shells from the study of Sun et al.[J.Phys.G:Nucl.Part.Phys.,45:075106(2018)],in which theαdecay was calculated by two different microscopic formulas.We find that theαdecay preformation factors are also related to NpNn.Combining with our previous studies[Sun et al.,Phys.Rev.C,94:024338(2016);Deng et al.,ibid.96:024318(2017);Deng et al.,ibid.97:044322(2018)]and that of Seif et al.,[Phys.Rev.C,84:064608(2011)],we suspect that this phenomenon of linear relationship for the nuclei around the above closed shells is model-independent.This may be caused by the effect of the valence protons(holes)and valence neutrons(holes)around the shell closures.Finally,using the formula obtained by fitting theαdecay preformation factor data calculated by the GLDM,we calculate theαdecay half-lives of these nuclei.The calculated results agree with the experimental data well.
基金Supported in part by the National Natural Science Foundation of China(12175100,11975132)the Construct Program of the Key Discipline in Hunan Province,the Research Foundation of the Education Bureau of Hunan Province,China(18A237)+2 种基金the Natural Science Foundation of Shandong Province,China(ZR2022JQ04)the Opening Project of Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment,University of South China(2019KFZ10)the Innovation Group of Nuclear and Particle Physics in USC,the Innovation Foundation for Postgraduate of Hunan Province,China(CX20230962)。
文摘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.
基金Supported in part by the National Natural Science Foundation of China(12175100,11975132)the construct program of the key discipline in hunan province+4 种基金the Research Foundation of Education Bureau of Hunan Province,China(18A237)the Shandong Province Natural Science Foundation,China(ZR2022JQ04)the Opening Project of Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment,University of South China(2019KFZ10)the Innovation Group of Nuclear and Particle Physics in USCHunan Provincial Innovation Foundation for Postgraduate(CX20210942)。
文摘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.
基金the National Natural Science Foundation of China(Grants No.12175100 and No.11975132)the Construct Program of the Key Discipline in Hunan Province+4 种基金the Research Foundation of Education Bureau of Hunan Province,China(Grant No.18A237)the Innovation Group of Nuclear and Particle Physics in USCthe Shandong Province Natural Science Foundation,China(Grant No.ZR2019YQ01)Hunan Provincial Innovation Foundation For Postgraduate(Grant No.CX20210942 and No.CX20200909)the Opening Project of Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment,University of South China(Grant No.2019KFZ10)。
文摘In this work,we systematically study theαdecay half-lives of 196 even–even nuclei using a two-potential approach improved by considering nuclear deformation.The results show that the accuracy of this model has been improved after considering nuclear deformation.In addition,we extend this model to predict theαdecay half-lives of Z=118 and 120 isotopes by inputting theαdecay energies extracted from the Weizsacker–Skyrme-type(WS-type)mass model,a simple nuclear mass formula,relativistic continuum Hartree–Bogoliubov theory and Duflo-Zuker-19(DZ19)mass model.It is useful for identifying the new superheavy elements or isotopes for future experiments.Finally,the predictedαdecay energies and half-lives of Z=118 and 120isotopes are analyzed,and the shell structure of superheavy nuclei is discussed.It shows that the shell effect is obvious at N=184,while the shell effect at N=178 depends on the nuclear mass model.
基金Supported in part by the National Natural Science Foundation of China(12175100)the construct program of the key discipline in Hunan province+3 种基金the Research Foundation of Education Bureau of Hunan Province,China(18A237)the Natural Science Foundation of Hunan ProvinceChina(2015JJ3103,2015JJ2123)the Innovation Group of Nuclear and Particle Physics in USC。
文摘In this study,we systematically investigate the proton radioactivity half-lives of 33 spherical nuclei based on the relationship between Skyrme parameters and the macroscopic quantities of nuclear matter.Using the two-potential approach with the spherical Skyrme-Hartree-Fock model,the correlation between proton radioactivity half-life and the macroscopic quantities is analyzed.Moreover,we obtain a new Skyrme parameter set by fitting the two most weighted macroscopic quantities.Compared with the Skyrme parameters MSLO and the theoretical model of proton radioactivity UDLP,the theoretical proton radioactivity half-life calculated using the new Skyrme parameter set can better reproduce the experimental data.
基金Supported in part by the National Naurll Science Foundation of China(11205083,11505100,11705055)the Construct Program of the Key Discipline in Hunan Provinee,the Research Foundation of Education Bureau of Hunan Province,China(15A I59,18A237)+4 种基金the Natural Science Foundation of Hunan Province,China(2015JJ3103,2015JJ2121,2018JJ2321)the Innovation Group of Nuclear and Particle Physics in UsSC,the Shandong Provinee Natural Science Foundation,China(ZR2015AQ007)the Hunan Provincial Innovation Foundation For Posigraduate(CX20200909)the National Innovation Training Foundation of China(201910555161)the Opening Projeet of Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment.University of South China(2019KFZ10)。
文摘In the present work,a two-parameter empirical formula is proposed,based on the Geiger-Nuttall law,to study two-proton( 2p )radioactivity.Using this formula,the calculated 2p radioactivity half-lives are in good agreement with the experimental data as well as with calculated results obtained by Goncalves et al.[Phys.Lett.B 774,14(2017)]using the effective liquid drop model(ELDM),Sreeja et al.[Eur.Phys.J.A 55,33(2019)]using a four-parameter empirical formula,and Cui et al.[Phys.Rev.C 101:014301(2020)]using a generalized liquid drop model(GLDM).In addition,this two-parameter empirical formula is extended to predict the half-lives of 22 possible 2p radioactivity candidates with 2p radioactivity released energy Q_(2p)>0 ,obtained from the latest evaluated atomic mass table AME2016.The predicted results are highly consistent with those obtained using other theoretical models such as the ELDM,GLDM and four-parameter empirical formula.
基金Supported by National Natural Science Foundation of China(Grant No.11205083 and No.11975132)the construct program of the key discipline in Hunan province,the Research Foundation of Education Bureau of Hunan Province,China(Grant No.18A237)+1 种基金the Innovation Group of Nuclear and Particle Physics in USC,the Shandong Province Natural Science Foundation,China(Grant No.ZR2019YQ01)the Hunan Provincial Innovation Foundation For Postgraduate(Grant No.CX20200909)。
文摘In this work,based on the liquid-drop model and considering the shell correction,we propose a simple formula to calculate the released energy of proton radioactivity(Q_(p)).The parameters of this formula are obtained by fitting the experimental data of 29 nuclei with proton radioactivity from ground state.The standard deviation between the theoretical values and experimental ones is only 0.157 Me V.In addition,we extend this formula to calculate 51 proton radioactivity candidates in region 51≤Z≤83 taken from the latest evaluated atomic mass table AME2016 and compared with the Q_(p)calculated by WS4 and HFB-29.The calculated results indicate that the evaluation ability of this formula for Q_(p)is inferior to WS4 while better than HFB-29.
基金National Natural Science Foundation of China(Grant No.12175100)the construct program of the key discipline in Hunan province,the Research Foundation of Education Bureau of Hunan Province,China(Grant No.18A237)+1 种基金the Innovation Group of Nuclear and Particle Physics in USC,the Shandong Province Natural Science Foundation,China(Grant No.ZR2022JQ04)the Hunan Provincial Innovation Foundation For Postgraduate(Grant No.CX20210942 and No.CX20220993)
文摘Based on the liquid-drop model and using the first derivative of the normalized Gaussian function to consider the shell correction,a simpleα-decay energy formula is proposed for heavy and superheavy nuclei.The values of corresponding adjustable parameters are obtained by fittingα-decay energies of 209 nuclei ranging from Z=90 to Z=118 with N≥140.The calculated results are in good agreement with the experimental data.The average and standard deviations between the experimental data and theoretical results are 0.141 and 0.190 Me V,respectively.For comparison,the reliable formulae proposed by Dong T K et al(2010,Phys.Rev.C 82,034320),Dong J M et al(2010,Phys.Rev.C 81,064309)and the WS3+nuclear mass model proposed by Wang N et al(2011,Phys.Rev.C 84,051303)are also used.The results indicate that our improved 7-parameter formula is superior to these empirical formulae and is largely consistent with the WS3+nuclear mass model.In addition,we extend this formula to predict theα-decay energies for nuclei with Z=117,118,119 and 120.The predicted results of these formulae are basically consistent.
基金Supported by National Natural Science Foundation of China under Grant Nos.11205083 and 11505100the construct program of the key discipline in Hunan province+7 种基金the Research Foundation of Education Bureau of Hunan ProvinceChina under Grant Nos.15A159 and18A237the Natural Science Foundation of Hunan ProvinceChina under Grant Nos.2015JJ3103,2015JJ2123the Innovation Group of Nuclear and Particle Physics in USCthe Shandong Province Natural Science Foundation,China under Grant No.ZR2015AQ007the National Innovation Training Foundation of China under Grant No.201910555161the Hunan Provincial Innovation Foundation for Postgraduate under Grant No.CX20190714
文摘In the present work,we predict the α decay half-lives of unknown even-even nuclei 296-308120 within the two-potential approach,whose α decay energy Qa is calculated using WS3+mass model.To reduce the deviations between the predictions and experimental data due to nuclear shell effect,the analytic formula of α decay hindrance factor is introduced to the two-potential approach,whose parameters had been extracted from even-even nuclei in the region of 82 <Z <126 and 152 <N ≤184 in our previous work [Deng et al.,Chin.Phys.C 42(2018) 044102].In addition,for comparing,we use a type of α decay general formula Universal Decay Law(UDL) and a semi-empirical formula in the superheavy nucleus(SEMFLS) to calculate the half-lives of even-even nuclei 296-308120.The results indicate that our predicted values and the calculated values of the above two empirical formulas are mutually confirmed.Meanwhile,we systematically study α decay chains of 296-308120 and predict the decay modes for superheavy nuclei to help to identify new superheavy isotopes.
基金Supported in part by the National Natural Science Foundation of China(11205083,11505100,11705055)the Construct Program of the Key Discipline in Hunan Province,the Research Foundation of Education Bureau of Hunan Province,China(18A237)+3 种基金the Natural Science Foundation of Hunan Province,China(2018JJ3324)the Innovation Group of Nuclear and Particle Physics in USC,the Shandong Province Natural Science Foundation,China(ZR2015AQ007)the National Innovation Training Foundation of China(201910555161)the Opening Project of Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment,University of South China(2019KFZ10)。
文摘In this study,a phenomenological model is proposed based on Wentzel-Kramers-Brillouin(WKB)theory and applied to investigate the two-proton(2p)radioactive half-lives of nuclei near or beyond the proton drip line.The total diproton-daughter nucleus interaction potential is composed of the Hulthen-type electrostatic term and the centrifugal term.The calculated 2p radioactive half-lives can accurately reproduce the existing 10 experimental datasets of five true 2p radioactive nuclei withσ=0.736.In addition,we extend this model to predict the half-lives of possible 2p radioactive nuclei whose 2p radioactivity is energetically allowed or observed but not yet quantified in NUBASE2016.The predicted results are in agreement with those obtained using the Gamow-like model,generalized liquid drop model,Sreeja formula,and Liu formula.
基金Supported in part by the National Natural Science Foundation of China(12175100,11975132)the Construct Program of the Key Discipline in Hunan Province+5 种基金the Research Foundation of Education Bureau of Hunan Province,China(21B0402,18A237)the Natural Science Foundation of Hunan Province,China(2018JJ2321)the Innovation Group of Nuclear and Particle Physics in USCthe Shandong Province Natural Science Foundation,China(ZR2019YQ01)the Hunan Provincial Innovation Foundation For Postgraduate(CX20210942)the Opening Project of Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment,University of South China(2019KFZ10)。
文摘In the present work,we systematically study the α-decay half-lives of uranium(Z=92) isotopes based on the Gamow model with a screened electrostatic barrier.There are only two adjustable parameters in our model i.e.the parameter g and the screening parameter t in the Hulthen potential for considering the screened electrostatic effect of the Coulomb potential.The calculated results are in good agreement with experimental data,and the corresponding root-mean-square(rms) deviations of uranium isotopes with α transition orbital angular momentum l=0 and l=2 are 0.141 and 0.340,respectively.Moreover,we extend this model to predict α-decay half-lives of uranium isotopes whose a decay is energetically allowed or observed but not yet quantified in NUBASE2020.For comparison,the modified Hatsukawa formula(XLZ),the unified Royer formula(DZR),the universal decay law(UDL) and the Viola-Seaborg-Sobiczewski formula(VSS) are also used.The predictions are basically consistent with each other.Meanwhile,the results also indicate that N=126 shell closure is still robust at Z=92 and the spectroscopic factor S_(α) is almost the same for uranium isotopes with the same l.
基金Supported by National Natural Science Foundation of China(Grant No.12175100 and No.11705055)the construct program of the key discipline in Hunan province+3 种基金the Research Foundation of Education Bureau of Hunan Province,China(Grant No.18A237)the Innovation Group of Nuclear and Particle Physics in USCthe Shandong Province Natural Science Foundation,China(Grant No.ZR2019YQ01)the Hunan Provincial Innovation Foundation For Postgraduate(Grant No.CX20210942)。
文摘In the present work,a phenomenological one-parameter model(OPM)based on the WentzelKramers-Brillouin(WKB)theory is applied to study the favored one proton radioactivity(the orbital angular momentum l taken away by the emitted proton is equal to zero)half-lives.The calculated results can reproduce the experimental data well within a factor of~3.In addition,we extend the OPM to predict the half-lives of possible favored one proton radioactivity nuclei whose decay is energetically allowed or observed but not quantified in NUBASE2020.For comparison,a universal decay law of one proton radioactivity(UDLP)is also used.It is obviously found that our predicted results are close to the ones using UDLP.The predictions are helpful for searching for the new nuclides with favored one proton radioactivity.
基金Supported in part by the National Natural Science Foundation of China(12175100,11975132)the Construct Program of the Key Discipline in Hunan Province,the Research Foundation of Education Bureau of Hunan Province,China(21B0402,18A237)+2 种基金the Natural Science Foundation of Hunan Province,China(2018JJ2321),the Innovation Group of Nuclear and Particle Physics in USC,the Natural Science Foundation of Shandong Province,China(ZR2022JQ04)the Innovation Foundation for Postgraduate of Hunan Province,China(CX20220993)the Opening Project of Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment,University of South China(2019KFZ10)。
文摘In this study,based on Wentzel-Kramers-Brillouin theory,we systematically investigate the cluster radioactivity half-lives of 22 nuclei ranging from^(221)Fr to^(242)Cm using a phenomenological model that considers the screened electrostatic effect of the Coulomb potential.In this model,there are two adjustable parameters,t and g,which are related to the screened electrostatic barrier and the strength of the spectroscopic factor,respectively.The calculated results indicate that this model can effectively reproduce the experimental data,with a corresponding rootmean-square deviation of 0.660.In addition,we extend this model to predict the half-lives of possible cluster radioactive candidates whose cluster radioactivities are energetically allowed or observed but not yet quantified in the evaluated nuclear properties table NUBASE2020.The predicted results are consistent with those obtained using other theoretical models and/or empirical formulas,including the universal decay law proposed by Qi et al.[Phys.Rev.C 80,044326(2009)],a semi-empirical model for bothαdecay and cluster radioactivity proposed by Santhosh et al.[J.Phys.G 35,085102(2008)],and a unified formula for the half-lives ofαdecay and cluster radioactivity proposed by Ni et al.[Phys.Rev.C 78,044310(2008)].
基金Supported by the National Natural Science Foundation of China(12175100,11975132)the Construct Program of the Key Discipline in Hunan Province+5 种基金the Research Foundation of Education Bureau of Hunan Province,China(18A237)the Natural Science Foundation of Hunan Province,China(2015JJ3103,2018JJ2321)the Innovation Group of Nuclear and Particle Physics in USCthe Shandong Province Natural Science Foundation,China(ZR2019YQ01)Hunan Provincial Innovation Foundation For Postgraduate(CX20210942)the Opening Project of Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment,University of South China(2019KFZ10)。
文摘Considering the preformation probability of the two emitted protons in the parent nucleus,we extend the Coulomb and proximity potential model(CPPM)to systematically study two-proton(2p)radioactivity half-lives of the nuclei close to proton drip line.The proximity potential chosen is Prox.81 proposed by Blocki et al.in 1981.Furthermore,we apply this model to predict the half-lives of possible 2p radioactive candidates whose 2p radioactivity is energetically allowed or observed but not yet quantified in the evaluated nuclear properties table NUBASE2016.The predicted results are in good agreement with those from other theoretical models and empirical formulas,namely the effective liquid drop model(ELDM),generalized liquid drop model(GLDM),Gamow-like model,Sreeja formula and Liu formula.
