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The temperature dependent width of the fission fragment distributions was simulated in the Langevin equation by taking two-parameter exponential form of the fission fragment mass variance at scission point for each fission event. The result can reproduce experimental data well, and it permits to make reliable estimate for unmeasured product yields near symmetry fission. 相似文献
83.
Properties of nuclei 13,15,N and 9B are investigated in the relativistic mean-field theory with NLz and NL3 force parameters.The calculated binding energies are very close to the experimental ones.The calculations show that the first excited state (1p1/2) in 9B,the first excited state (2s1/2)in 13 N and the second excited state(2s1/2) in 15N are weakly bound .In particular,for 13N and 15N,the proton density distributions in the two above excited states have a long tail and the rms radii of the last proton are greatly larger compared with their respective matter radii.It is predicted that a proton halo exists in the first excited state of 13N and in the second excited state of 15N,respectively.It also indicates that the first excited state in 9B is a proton skin state. 相似文献
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85.
方德清 郭威 马春旺 王鲲 颜廷志 马余刚 蔡翔舟 沈文庆 任中洲 孙志宇 M. Hosoi T. Izumikawa R. Kanungo S. Nakajima T. Ohnishi T. Ohtsubo A. Ozawa T. Suda K. Sugawara T. Suzuki A. Takisawa K. Tanaka T. Yamaguchi I. Tanihata 《中国物理 C》2008,32(Z2):34-37
The longitudinal momentum distribution (P//) of fragments after one-proton removal from 23Al and reaction cross sections (σR) for 23,24Al on carbon target at 74A MeV have been measured simultaneously. An enhancement in σR is observed for 23Al compared with 24Al. The full width at half maximum of the P// distribution for 22Mg fragments has been determined to be 232±28 MeV/c. Analysis of P// using the Few-Body Glauber Model indicates a dominant d-wave configuration for the valence proton in the ground state of 23Al. The exotic structure in 23Al is discussed. 相似文献
86.
Using an isospin-dependent quantum molecular dynamics (IQMD) model, we study the 15C induced reactions from 30-120 MeV/nucleon systematically. Here the valence neutron of 15C is assigned at both 1d5/2 and 2s1/2 states respectively in order to study the density effect of reaction mechanism. It is believed that the existent neutron halo structure at the 2s1/2 state of 15C will affect the light particle emission evidently. In our calculation, the different density distributions of 15C at two states are calculated by relativistic mean field (RMF) model and introduced in the initiation of IQMD model, respectively. It is found that some observables such as emission fragmentation multiplicity, emission neutron/proton ratio and emission neutrons’ kinetic energy spectrum are sensitive to the initial density distribution. 相似文献
87.
Using an isospin-dependent quantum molecular dynamics (IQMD) model, we study the 15C induced reactions from 30—120 MeV/nucleon systematically. Here the valence neutron of 15C is assigned at both 1d 5/2 and 2s 1/2 states respectively in order to study the density effect of reaction mechanism. It is believed that the existent neutron halo structure at the 2s 1/2 state of 15C will affect the light particle emission evidently. In our calculation, the different density distributions of 15C at two states are calculated by relativistic mean field (RMF) model and introduced in the initiation of IQMD model, respectively. It is found that some observables such as emission fragmentation multiplicity, emission neutron/proton ratio and emission neutrons' kinetic energy spectrum are sensitive to the initial density distribution. 相似文献
88.
We apply a statistical-evaporation model (HIVAP) to calculate the cross sections of superheavy elements, mainly about actinide targets and compare with some available experimental data. A reaction channel ^30Si 4 ^243Am is proposed for the synthesis of the element Z=109 and the cross section is estimated. 相似文献
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90.