共查询到20条相似文献,搜索用时 78 毫秒
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描述了利用Glauber模型计算反应截面的一种方法 .该方法对Glauber模型中输入的密度分布形式进行了修正 ,计算了丰质子同中子核素 (N =3 )的激发函数 .对于该同中子素链 ,采用修正的密度分布得到的激发函数与HO分布得到的激发函数相比 ,在大于 1 0 0MeV/u的能量区域 ,两者都与实验值符合得很好 ,而在中能区 (小于 1 0 0MeV/u) ,用修正的密度分布计算得到的激发函数与实验值之间的差距较HO分布明显减小 ,并保持对所有计算的核核芯密度基本相同 . 相似文献
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描述了利用Glauber模型计算反应截面的一种方法。该方法对Glauber模型中输入的密度分布形式进行了修正,计算了丰质子同中子核素(N=3)的激发函数。对于该同中子素链,采用修正的密度分布得到的激发函数与HO分布得到的激发函数要比,在大于100MeV/u的能量区域,两者都与实验值符合很好,而在中能区(小于100MeV/u),用修正的密度分布计算得到的激发函数与实验值之间的差距较HO分布明显减小,并保持对所有计算的核核芯密度基本相同。 相似文献
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用密度可变的连续介质模型计算了A≥100区域β稳定核宏观位能曲面,得到了合理的裂变位垒高度,预言了鞍点态裂变核电荷的双重心分布. 相似文献
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本文应用原子核的宏观模型提出了一种比较简单的计算变形核电荷密度的方法.具体计算了192Os、154Gd、152Sm、174Yb、及144,148,150,152Sm等原子核的电荷密度分布.结果表明,宏观模型计算的结果能较好地与实验测量结果相符合.因此,只要根据变形核基态到各转动态跃迁几率或电多极矩的实验值,则可按本文方法,从理论上预言变形核的电荷密度分布. 相似文献
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胡正国 王猛 徐瑚珊 孙志宇 王建松 肖国青 詹文龙 肖志刚 毛瑞士 张宏斌 赵铁成 徐治国 王玥 陈若富 黄天衡 高辉 贾飞 付芬 高启 韩建龙 章学恒 郑川 余玉洪 樊瑞睿 李波 郭忠言 《物理学报》2008,57(5):2866-2870
在兰州重离子加速器国家实验室(HIRFL)放射性次级束流线(RIBLL)上,用束流透射法测量了丰中子奇异核17B与C靶反应的总截面.假定17B具有15B(核芯)+2n结构,采用Gauss+HO形式的密度分布和零力程Glauber模型进行计算的结果可以很好地拟合实验数据,并得出17B的密度分布有一个很大的弥散,表明17B是双中子晕核.
关键词:
丰中子奇异核
反应总截面
Glauber模型
密度分布 相似文献
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Published data on the intensities of two-step cascades to 12 final-state levels of the 96Mo nucleus are approximated by using a set of possible random dependences of the level density and radiative strength functions for primary E1 and M1 transitions. The average values of these parameters of gamma decay for any excitation energies and for gamma transitions agree well with basic dependences revealed to date from similar experiments for 42 nuclei in the mass-number range 40 ≤ A ≤ 200, but they are inconsistent with the generally accepted ideas of the parameters of the cascade gamma decay of compound states of nuclei having high level densities. 相似文献
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R. Albrecht T. C. Awes C. Baktash P. Beckmann F. Berger R. Bock G. Claesson L. Dragon R. L. Ferguson A. Franz S. Garpmann R. Glasow H. A. Gustafsson H. H. Gutbrod K. H. Kampert B. W. Kolb P. Kristiansson I. Y. Lee H. Lohner I. Lund F. E. Obenshain A. Oskarsson I. Otterlund T. Peitzmann S. Persson F. Plasil A. M. Poskanzer M. Purschke H. G. Ritter R. Santo H. R. Schmidt T. Siemiarczuk S. P. Sorensen E. Stenlund G. R. Young WA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1988,38(1):3-14
Results based on calorimetric measurements are presented from reactions of 60A GeV and 200A GeV16O projectiles with C, Cu, Ag, and Au nuclei. Minimum-bias cross sections are discussed. Energy spectra measured at zero degrees and transverse-energy distributions for the pseudorapidity range 2.4≦η≤5.5 are shown. An analysis of the average transverse energy in terms of the number of participating nucleons and the number of binary nucleon-nucleon collisions is presented. Estimates of nuclear stopping and of attained energy densities are made. 相似文献
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A combination of the exciton and evaporation models is used to describe photonucleon reactions induced in heavy and medium-mass nuclei by photons of energy in the range 7 ≤ E γ ≤ 140 MeV. The formation of a giant dipole resonance and quasideuteron absorption are considered as two mechanisms that are responsible for the photoexcitation of a nucleus in the energy regions E γ ? 20 MeV and E γ ? 40 MeV, respectively. As is well known, the densities of particle-hole states are employed in the exciton model, and these quantities are calculated on the basis of the Fermi gas model. This makes it possible to take into account the effect of the energy dependence of single-particle and single-hole densities of states on the rate of emission and intranuclear processes. The model in question is applied to describing partial photonucleon cross sections for 119Sn, 140Ce, 181Ta, and 208Pb nuclei. 相似文献
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O. V. Bespalova T. A. Ermakova A. A. Klimochkina E. A. Romanovsky T. I. Spasskaya 《Bulletin of the Russian Academy of Sciences: Physics》2013,77(4):397-401
Occupation probabilities of neutron and proton single-particle orbits are estimated for a number of spherical and close to spherical nuclei with 20 ≤ Z ≤ 50 and 20 ≤ N ≤ 82 near the Fermi energy. The estimates are made according to the formula of the BCS theory with single-particle energies calculated using the mean-field model with dispersive optical potential. The closeness of the occupation probabilities to 0 and 1 is demonstrated for nuclei with traditional and new magic numbers. 相似文献
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The half-lives of deformed nuclei are reported for 67≤Z≤91. We consider an angle-dependent potential which yields multiple approximations. The results are in better agreement with the experimental data when the multiple approximation is solely considered for the daughter nuclei. 相似文献
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V. Yu. Denisov 《Physics of Atomic Nuclei》2005,68(7):1133-1137
For nuclei where the number of protons lies in the range 76 ≤ Z ≤ 400, proton and neutron shell corrections are calculated along the beta-stability line described by Green’s formula. The magic numbers of protons and neutrons are determined for ultraheavy nuclei. Alpha-decay half-lives and fission barriers are estimated for ultraheavy doubly magic nuclei. 相似文献
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An analysis of the entire body of data on the intensities of two-step gamma cascades studied in thermal-neutron capture for more than 50 nuclei from the range 27 ≤ A ≤ 199 suggests that such processes should be described in terms of model concepts that are much more involved than those currently adopted by experimentalists. According to the results of this analysis, models of relevant parameters, such as the density of excited levels and radiative strength functions for dipole gamma transitions, should take into account more explicitly the coexistence and interaction of quasiparticle and phonon interactions. A direct inclusion of the idea that a second-order phase transition occurs and affects not only level densities but also radiative strength functions for dipole transitions may prove to be necessary. These conclusions concern primarily the excitation-energy region below a value of about 0.5B n . 相似文献
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K P SANTHOSH 《Pramana》2014,82(4):705-715
We present here, an overview and progress of the theoretical works on the isomeric state α decay, α decay fine structure of even–even, even–odd, odd–even and odd–odd nuclei, a study on the feasibility of observing α decay chains from the isotopes of the superheavy nuclei Z = 115 in the range 271 ≤A ≤ 294 and the isotopes of Z = 117 in the range 270 ≤A ≤ 301, within the Coulomb and proximity potential model for deformed nuclei (CPPMDN). The computed half-lives of the favoured and unfavoured α decay of nuclei in the range 67 ≤Z ≤ 91 from both the ground state and isomeric state, are in good agreement with the experimental data and the standard deviation of half-life is found to be 0.44. From the α fine structure studies done on various ranges of nuclei, it is evident that, for nearly all the transitions, the theoretical values show good match with the experimental values. This reveals that CPPMDN is successful in explaining the fine structure of even–even, even–odd, odd–even and odd–odd nuclei. Our studies on the α decay of the superheavy nuclei 271?294115 and 270?301117 predict 4 α chains consistently from 284,285,286115 nuclei and 5α chains and 3α chains consistently from 288?291117 and 292117, respectively. We thus hope that these studies on 284?286115 and 288?292117 will be a guide to future experiments. 相似文献
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LIU Jing-Jing 《中国物理C(英文版)》2010,34(2)
Based on WeinbergoSalam theory the bremsstrahlung neutrino energy loss for nuclei ~(24)Mg, ~(28)Si, ~(32)S, ~(40)Ca and ~(56)Fe are investigated in strong electron screening. Our results are compared with those of Dicus' and show that the latter are higher by 2 orders of magnitude in the density-temperature region of 10~8 g/cm~3 ≤ρ/μ_e≤10~(11) g/cm~3 and 2.5 ≤ T_9 ≤4.5. On the other hand, the factor C shows that the maximum differences are 99.16%, 99.13%, 99.12%, 99.055%, 99.040% corresponding to the nuclei ~(24)Mg, ~(28)Si, ~(32)S, ~(40)Ca and ~(56)Fe. 相似文献