The nuclear dynamical deformation,the fusion probability and the evaporation residue(ER) cross sections for the synthesis of superheavy nuclei are studied with the di-nuclear system model and the related dynamical pot...The nuclear dynamical deformation,the fusion probability and the evaporation residue(ER) cross sections for the synthesis of superheavy nuclei are studied with the di-nuclear system model and the related dynamical potential energy surface.The intrinsic energy and the maximum dynamical deformations for48Ca+248Cm are calculated.The effect of dynamical deformation on the potential energy surface and fusion is investigated.It is found that the dynamical deformation influences the potential energy surface and fusion probability significantly.The dependence of the fusion probability on the angular momentum is investigated.The ER cross sections for some superheavy nuclei in48Ca induced reactions are calculated and it is found that the theoretical results are in good agreement with the experimental results.展开更多
A summary is given on the activation cross section measurements performed byChina Institute of Atomic Energy(CIAE),Lanzhou University(LU),Peking University(PU)and Sichuan University(SU)from 1989 to 1994 for ge...A summary is given on the activation cross section measurements performed byChina Institute of Atomic Energy(CIAE),Lanzhou University(LU),Peking University(PU)and Sichuan University(SU)from 1989 to 1994 for generation of long-lived radionuclides of im-portance in fusion reactor technology.The cross sections are measured for the reactions <sup>109</sup>Ag(n,2n)<sup>108</sup>Ag<sup>m</sup>,<sup>151</sup>Eu(n,2n)<sup>150</sup>Eu<sup>m</sup>,<sup>153</sup>Eu(n,2n)<sup>152</sup>Eu<sup>8</sup>,<sup>159</sup>Tb(n,2n)<sup>158</sup>Tb,<sup>179</sup>Hf(n,2n )<sup>178</sup>Hf<sup>m2</sup>,<sup>182</sup>W(n,n′α)<sup>178</sup>Hf<sup>m2</sup>,<sup>187</sup>Re(n,2n)<sup>186</sup>Re<sup>m</sup> and <sup>193</sup>Ir(n,2n)<sup>192</sup>Ir<sup>m2</sup>at 14 MeV,<sup>109</sup>Ag(n,2n)<sup>108</sup>Ag<sup>m</sup>,<sup>151</sup>Eu(n,2n)<sup>150</sup>Eu<sup>m</sup>,<sup>159</sup>Tb(n,2n)<sup>158</sup>Tb and <sup>179</sup>Hf(n,2n)<sup>178</sup>Hf<sup>m2</sup>at 9.5 and 9.9 MeV,and<sup>98</sup>Mo(n,γ)<sup>199</sup>Mo(β<sup>-</sup>)→<sup>99</sup>Tc,<sup>165</sup>Ho(n.γ)<sup>166</sup>Ho<sup>m</sup> and <sup>151</sup>Eu(n,γ)<sup>152</sup>Eu<sup>8</sup> in the energy range of20~1100 keV.Some of them were calculated by systematic and HFTT code,which was basedon the compound nucleus evaporation and the preequilibrium exciton model.展开更多
In recent several years,the tensor force,one of the most important components of the nucleon-nucleon force,has been implemented in time-dependent density functional theories and it has been found to influence many asp...In recent several years,the tensor force,one of the most important components of the nucleon-nucleon force,has been implemented in time-dependent density functional theories and it has been found to influence many aspects of low-energy heavy-ion reactions,such as dissipation dynamics,sub-barrier fusions,and low-lying vibration states of colliding partners.Especially,the effects of tensor force on fusion reactions have been investigated from the internuclear potential to fusion crosssections systematically.In this work,we present a mini review on the recent progress on this topic.Considering the recent progress of low-energy reaction theories,we will also mention more possible effects of the tensor force on reaction dynamics.展开更多
We investigated ^(50,52-54)Cr-induced fusion reactions for the synthesis of the superheavy element in the 104≤Z≤122 range.The cross sections produced in this investigation using ^(54)Cr projectiles were compared wit...We investigated ^(50,52-54)Cr-induced fusion reactions for the synthesis of the superheavy element in the 104≤Z≤122 range.The cross sections produced in this investigation using ^(54)Cr projectiles were compared with those obtained in prior experiments.The estimated cross sections from this analysis are consistent with the findings of prior studies.From the current study,the predicted cross section was found to be 42fb at 236 MeV for ^(53)Cr+^(243)Am,23.2 fb at 236 MeV for ^(54)Cr+^(247)Cm,95.6 fb at 240 MeV for ^(53)Cr+248Bk,and 1.33 fb at 242 MeV for ^(53)Cr+250Cf.Consequently,these projected cross sections with excitation energy and beam energy will be useful in future Cr-induced fusion reaction investigations.展开更多
Nuclear fusion is one of the world's primary energy sources. Studies on the structural fusion materials are very important in terms of the development of fusion technology. Chromium, nickel, zinc, scandium, titani...Nuclear fusion is one of the world's primary energy sources. Studies on the structural fusion materials are very important in terms of the development of fusion technology. Chromium, nickel, zinc, scandium, titanium,and yttrium are important structural fusion materials. In this paper, for use in nuclear science and technology applications, the excitation functions of the ^(50)Cr(d, n)^(51)Mn,^(58)Ni(d, n)^(59)Cu,^(64)Zn(d, n)^(65)Ga,^(66)Zn(d, n)^(67)Ga,^(45)Sc(d,2n)^(45)Ti,^(47)Ti(d, 2n)^(47)V,^(48)Ti(d, 2n)^(48)V, and ^(89)Y(d, 2n)^(89)Zr nuclear reactions were investigated. The calculations that are based on the pre-equilibrium and equilibrium reaction processes were performed using ALICE–ASH computer code. A comparison with geometry-dependent hybrid model has been made using the initial exciton numbers n_0= 4–6 and level density parameters α = A/5; A/8; A/11.Also, the present model-based calculations were compared with the cross sections obtained using the formulae suggested from our previous studies. Furthermore, the cross section results have been compared with TENDL data based on TALYS computer code and the measured data in the literature.展开更多
The neutron flow model predicts that neutrons start to flow freely between the approaching nuclei ^58Fe and ^208 pb at s=3fm, a length in which the effective surfaces of these nuclei are 3 fm apart. As a result of neu...The neutron flow model predicts that neutrons start to flow freely between the approaching nuclei ^58Fe and ^208 pb at s=3fm, a length in which the effective surfaces of these nuclei are 3 fm apart. As a result of neutron flow, the N/Z value rapidly reaches an equilibrium distribution. Meanwhile the system, originally in the fusion valley, is injected into the asymmetric fission valley. The dynamic process of the composite nucleus in the asymmetric fission valley is treated with a two-parameter Smoluchowski equation. It is shown that the probability to overcome the asymmetric fission barrier and to achieve compound nucleus configuration, hence the fusion cross section is obviously suppressed due to the effect of isospin equilibrium.展开更多
Abstract The effects of mass asymmetry on the production of superheavy nuclei(SHN),within the dinuclear system model,are investigated in this study.It is observed that the fusion probability decreases with decreasing ...Abstract The effects of mass asymmetry on the production of superheavy nuclei(SHN),within the dinuclear system model,are investigated in this study.It is observed that the fusion probability decreases with decreasing mass asymmetry.A total of 192 possible combinations of projectiles from O to Ti and targets with half-lives longer than30 days for producing SHN^(264)Db,^(265)Db,^(267)Sg,^(268)Bh,268Sg,^(269)Bh,^(271)Hs,^(271)Mt,^(272)Hs,^(272)Mt,^(273)Mt,^(274)Ds,275Ds,^(275)Rg,^(276)Ds,^(276)Rg,^(277)Rg,^(278)Cn,^(279)Cn,and^(280)Cn are examined.Further,the optimal combinations and incident energies for synthesizing these nuclei are predicted.Most of the cross sections for production of SHNare larger than 10 pb;therefore,the process can be carried out with the available experimental equipment.展开更多
The laser fusion criterion is known as the ρR-Criterion, also called high-gain condition. This parameter is temperature dependent and can be calculated by R-matrix method. This method is applied for determining impro...The laser fusion criterion is known as the ρR-Criterion, also called high-gain condition. This parameter is temperature dependent and can be calculated by R-matrix method. This method is applied for determining improved fusion cross-section for the reactions T(d,n)4He, 3He(d,p)4He, D(d,p)T, D(d,n)3He. In this paper the time dependent reaction rate equations for fusion reaction T(d,n)4He are solved and by using the obtained results we computed the fu- sion power density, energy gain versus temperature and ρR-parameter. The obtained results show that a suitable com- bination may be a deuterium fraction fD=0.65 and fT=0.35 which would lead 30% reduction in the tritium content of the fuel mixture, and this choice would not change the energy gain value very much. Finally, the obtained energy gain for D-T reaction by using R-matrix is in good agreement with other theories.展开更多
Fusion reactions with a weakly bound projectile are studied using the double-folding model along with a repulsive interaction modifying term. Using this modified potential, including nuclear matter incompressibility e...Fusion reactions with a weakly bound projectile are studied using the double-folding model along with a repulsive interaction modifying term. Using this modified potential, including nuclear matter incompressibility effects, the fusion reaction cross sections and suppression parameters are calculated for 9Be+209Bi, 208spb, 29Si and 27A1 reactions. The results show that applying these effects at agreement between the calculated and experimental cross sections parameter. energies near the Coulomb barrier improves the and modifies the mean values of the suppression展开更多
基金Supported by National Natural Science Foundation of China(NSFC) projects (Nos.10975100,11275098,10979066,11275248,11175252 and 11120101005)MOST of China(No.2013CB834400) the Knowledge Innovation Project of CAS(Nos.KJCX2-EW-N01 and KJCX2-YW-N32)
文摘The nuclear dynamical deformation,the fusion probability and the evaporation residue(ER) cross sections for the synthesis of superheavy nuclei are studied with the di-nuclear system model and the related dynamical potential energy surface.The intrinsic energy and the maximum dynamical deformations for48Ca+248Cm are calculated.The effect of dynamical deformation on the potential energy surface and fusion is investigated.It is found that the dynamical deformation influences the potential energy surface and fusion probability significantly.The dependence of the fusion probability on the angular momentum is investigated.The ER cross sections for some superheavy nuclei in48Ca induced reactions are calculated and it is found that the theoretical results are in good agreement with the experimental results.
基金The project cartied OHt under IAEA Research Agreement No 5060/CF
文摘A summary is given on the activation cross section measurements performed byChina Institute of Atomic Energy(CIAE),Lanzhou University(LU),Peking University(PU)and Sichuan University(SU)from 1989 to 1994 for generation of long-lived radionuclides of im-portance in fusion reactor technology.The cross sections are measured for the reactions <sup>109</sup>Ag(n,2n)<sup>108</sup>Ag<sup>m</sup>,<sup>151</sup>Eu(n,2n)<sup>150</sup>Eu<sup>m</sup>,<sup>153</sup>Eu(n,2n)<sup>152</sup>Eu<sup>8</sup>,<sup>159</sup>Tb(n,2n)<sup>158</sup>Tb,<sup>179</sup>Hf(n,2n )<sup>178</sup>Hf<sup>m2</sup>,<sup>182</sup>W(n,n′α)<sup>178</sup>Hf<sup>m2</sup>,<sup>187</sup>Re(n,2n)<sup>186</sup>Re<sup>m</sup> and <sup>193</sup>Ir(n,2n)<sup>192</sup>Ir<sup>m2</sup>at 14 MeV,<sup>109</sup>Ag(n,2n)<sup>108</sup>Ag<sup>m</sup>,<sup>151</sup>Eu(n,2n)<sup>150</sup>Eu<sup>m</sup>,<sup>159</sup>Tb(n,2n)<sup>158</sup>Tb and <sup>179</sup>Hf(n,2n)<sup>178</sup>Hf<sup>m2</sup>at 9.5 and 9.9 MeV,and<sup>98</sup>Mo(n,γ)<sup>199</sup>Mo(β<sup>-</sup>)→<sup>99</sup>Tc,<sup>165</sup>Ho(n.γ)<sup>166</sup>Ho<sup>m</sup> and <sup>151</sup>Eu(n,γ)<sup>152</sup>Eu<sup>8</sup> in the energy range of20~1100 keV.Some of them were calculated by systematic and HFTT code,which was basedon the compound nucleus evaporation and the preequilibrium exciton model.
文摘基于广义约化R矩阵理论,使用RAC程序(R-matrix analysis code)综合分析了^(6)He系统中所有可以利用的实验数据,给出了氚核入射10-2—20 MeV能量范围内主要反应道的评价核数据.其中积分截面包括T(t,2n)^(4)He,T(t,n)^(5)He,T(t,d)^(4)H;微分截面包括T(t,2n)^(4)He,T(t,n)^(5)He,T(t,d)^(4)H,T(t,t)T.结果表明,RAC的评价结果与实验数据和ENDF/B-Ⅷ.1的评价数据整体符合良好.重点关注T(t,2n)^(4)He反应,评价值在10-2—20 MeV范围内与已有实验数据一致,在2.9 Me V附近出现由2+能级主导的共振,在1.9 Me V处,已有实验同时测量了积分截面和角分布,本工作的评价结果在两类数据上均表现出良好的一致性,积分截面与微分截面的联合约束有效提升了R矩阵参数的稳定性和评价结果的可靠性.基于6He系统的整体评价,进一步补充了T(t,n)^(5)He和T(t,d)^(4)H反应的截面数据.本工作完善了聚变反应相关的数据基础,并为后续与镜像系统6Be系统的联合分析奠定了基础.
基金supported by the National Natural Science Foundation of China(Grants No.11975237,No.11575189,and No.11790325)the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB34010000 and No.XDPB15)
文摘In recent several years,the tensor force,one of the most important components of the nucleon-nucleon force,has been implemented in time-dependent density functional theories and it has been found to influence many aspects of low-energy heavy-ion reactions,such as dissipation dynamics,sub-barrier fusions,and low-lying vibration states of colliding partners.Especially,the effects of tensor force on fusion reactions have been investigated from the internuclear potential to fusion crosssections systematically.In this work,we present a mini review on the recent progress on this topic.Considering the recent progress of low-energy reaction theories,we will also mention more possible effects of the tensor force on reaction dynamics.
文摘We investigated ^(50,52-54)Cr-induced fusion reactions for the synthesis of the superheavy element in the 104≤Z≤122 range.The cross sections produced in this investigation using ^(54)Cr projectiles were compared with those obtained in prior experiments.The estimated cross sections from this analysis are consistent with the findings of prior studies.From the current study,the predicted cross section was found to be 42fb at 236 MeV for ^(53)Cr+^(243)Am,23.2 fb at 236 MeV for ^(54)Cr+^(247)Cm,95.6 fb at 240 MeV for ^(53)Cr+248Bk,and 1.33 fb at 242 MeV for ^(53)Cr+250Cf.Consequently,these projected cross sections with excitation energy and beam energy will be useful in future Cr-induced fusion reaction investigations.
文摘Nuclear fusion is one of the world's primary energy sources. Studies on the structural fusion materials are very important in terms of the development of fusion technology. Chromium, nickel, zinc, scandium, titanium,and yttrium are important structural fusion materials. In this paper, for use in nuclear science and technology applications, the excitation functions of the ^(50)Cr(d, n)^(51)Mn,^(58)Ni(d, n)^(59)Cu,^(64)Zn(d, n)^(65)Ga,^(66)Zn(d, n)^(67)Ga,^(45)Sc(d,2n)^(45)Ti,^(47)Ti(d, 2n)^(47)V,^(48)Ti(d, 2n)^(48)V, and ^(89)Y(d, 2n)^(89)Zr nuclear reactions were investigated. The calculations that are based on the pre-equilibrium and equilibrium reaction processes were performed using ALICE–ASH computer code. A comparison with geometry-dependent hybrid model has been made using the initial exciton numbers n_0= 4–6 and level density parameters α = A/5; A/8; A/11.Also, the present model-based calculations were compared with the cross sections obtained using the formulae suggested from our previous studies. Furthermore, the cross section results have been compared with TENDL data based on TALYS computer code and the measured data in the literature.
基金Supported by the National Natural Science Foundation of China under Grants Nos 10235020 and 10235030, and the Major State Basic Research Development Programme under Grant No G200007400.
文摘The neutron flow model predicts that neutrons start to flow freely between the approaching nuclei ^58Fe and ^208 pb at s=3fm, a length in which the effective surfaces of these nuclei are 3 fm apart. As a result of neutron flow, the N/Z value rapidly reaches an equilibrium distribution. Meanwhile the system, originally in the fusion valley, is injected into the asymmetric fission valley. The dynamic process of the composite nucleus in the asymmetric fission valley is treated with a two-parameter Smoluchowski equation. It is shown that the probability to overcome the asymmetric fission barrier and to achieve compound nucleus configuration, hence the fusion cross section is obviously suppressed due to the effect of isospin equilibrium.
基金supported by the National Natural Science Foundation of China under Grant No.11605296the Natural Science Foundation of Guangdong Province,China(Grant No.2016A030310208)the National Natural Science Foundation of China under Grant Nos.11875328,11405278 and 11605270
文摘Abstract The effects of mass asymmetry on the production of superheavy nuclei(SHN),within the dinuclear system model,are investigated in this study.It is observed that the fusion probability decreases with decreasing mass asymmetry.A total of 192 possible combinations of projectiles from O to Ti and targets with half-lives longer than30 days for producing SHN^(264)Db,^(265)Db,^(267)Sg,^(268)Bh,268Sg,^(269)Bh,^(271)Hs,^(271)Mt,^(272)Hs,^(272)Mt,^(273)Mt,^(274)Ds,275Ds,^(275)Rg,^(276)Ds,^(276)Rg,^(277)Rg,^(278)Cn,^(279)Cn,and^(280)Cn are examined.Further,the optimal combinations and incident energies for synthesizing these nuclei are predicted.Most of the cross sections for production of SHNare larger than 10 pb;therefore,the process can be carried out with the available experimental equipment.
文摘The laser fusion criterion is known as the ρR-Criterion, also called high-gain condition. This parameter is temperature dependent and can be calculated by R-matrix method. This method is applied for determining improved fusion cross-section for the reactions T(d,n)4He, 3He(d,p)4He, D(d,p)T, D(d,n)3He. In this paper the time dependent reaction rate equations for fusion reaction T(d,n)4He are solved and by using the obtained results we computed the fu- sion power density, energy gain versus temperature and ρR-parameter. The obtained results show that a suitable com- bination may be a deuterium fraction fD=0.65 and fT=0.35 which would lead 30% reduction in the tritium content of the fuel mixture, and this choice would not change the energy gain value very much. Finally, the obtained energy gain for D-T reaction by using R-matrix is in good agreement with other theories.
文摘Fusion reactions with a weakly bound projectile are studied using the double-folding model along with a repulsive interaction modifying term. Using this modified potential, including nuclear matter incompressibility effects, the fusion reaction cross sections and suppression parameters are calculated for 9Be+209Bi, 208spb, 29Si and 27A1 reactions. The results show that applying these effects at agreement between the calculated and experimental cross sections parameter. energies near the Coulomb barrier improves the and modifies the mean values of the suppression