共查询到20条相似文献,搜索用时 437 毫秒
1.
应用Glauber核-核散射理论,在“刚体炮弹近似”下计算了高α粒子在4He靶核上的弹性散射.结果显示,理论对于中等动量转移以下的实验结果给出令人满意的描述. 相似文献
2.
测量了89Y(α,p)92Zr反应的基态和几个激发态的微分截面及89Y(α,α)89Y弹性散射微分截面.利用89Y、92Zr的壳模型波函数对该反应基态和第一激发态的实验数据进行了完全微观DWBA理论分析.具有核芯激发组态的核波函数明显地改善了不同末态的截面相对强度,而对角分布的形状影响甚微.它表明具有核芯激发组态的89Y、92Zr核波函数有较好的实验基础.最后,讨论了89Y(α,p)92Zr反应的截面绝对值问题,揭示了α浅势阱的重要性. 相似文献
3.
4.
正在研制的上海激光电子γ源是MeV量级的高品质γ光束线站,基于该装置可以开展一系列核天体物理实验, 从而更准确的确定各天体核合成反应的反应率. 本文研究了天体核合成中的关键反应12C(α,γ)16O的反应率. 根据多组实验和理论截面数据分别计算了反应率, 并给出了这些反应率计算结果的平均值和统计误差. 根据该结果拟合了理论反应率的解析形式, 确定了新的参数. 进而给出俘获反应12C(α,γ)16O在He燃烧环境下的反应率和误差, 并讨论了电子屏蔽效应对天体反应率的修正. 相似文献
5.
利用质子散射作为手段对16O的α粒子结构模型进行了检验.基于4α结构模型,对跨度整个中能区的质子与16O核的弹性角分布进行了无自由参数的计算.理论与实验基本符合. 相似文献
6.
运用实验的pN散射振幅和多次散射理论,在冲量近似下考虑反质子能量从180MeV至1800MeV的光学势,发现此能区反质子光学势的虚部强度在130—140MeV附近.用所获得的光学势,计算12C,26O,40Ca和208Pb等满壳层核在五个能量下的弹性散射微分截面.看到所用的光学势,在180MeV能很好地符合实验数值.本文还预示了此能区在各个核上的理论结果. 相似文献
7.
8.
9.
10.
用屏栅电离室测量了入射中子能量为5.1MeV的58Ni(n,α)55Fe核反应的α粒子角分布,238U裂变电离室作中子注量率的测量,测得该能点58Ni(n,α)55Fe的总截面为(47.4±5.0)mb.用中国核数据中心推荐的理论计算程序UNF计算了在1—8MeV能区58Ni(n,p)58Co,58Ni(n,α)55Fe的反应截面和入射中子能量为5.1MeV的58Ni(n,α)反应角分布.理论和测量数据的比较说明,用复合核模型来描写该能点的角分布是可行的. 相似文献
11.
12.
偶-偶超重核基态性质的理论研究 总被引:2,自引:0,他引:2
在形变的相对论平均场模型下采用NL Z2,TMA两套参数对一些偶 偶核基态性质进行了系统的计算,并将理论计算的结合能、α衰变能与已知的实验数据进行了对比分析.结果发现两方面的数据能够比较好地吻合,从而验证了相对论平均场模型对超重核研究是可行的.同时在计算中给出了未知核素基态性质的计算结果,可供以后在理论或实验上研究超重核时参考. The ground state properties of the even even nuclei with proton number Z=94-104 have been systematically calculated in the deformed relativistic mean field (RMF) theory with two sets of force parameters, TMA and NL Z2. Comparing the calculated binding energies and alpha decay energys with the experimental ones, it is found that theoretical results are in good agreement with experimental data. The reliability of the RMF model for even even superheavy nuclei has been tested by this comparison... 相似文献
13.
14.
ZHI Qi-Jun REN Zhong-Zhou ZHANG Xiao-Ping ZHOU Xiao-Hong GAN Zai-Guo QIN Zhi XU Hu-Shan 《中国物理C(英文版)》2008,32(1)
We investigate the ground state properties of some superheavy nuclei, which may be synthesized in future experiments. Special emphases are placed on the alpha decay energies and half-lives. The alpha decay energies and half-lives from different theoretical models are compared and discussed comprehensively. Through these calculations and comparisons, the optimal superheavy elements to be synthesized in future experiments are proposed theoretically. 相似文献
15.
基于推广的液滴模型(GLDM) 理论框架,计算了292-310122 同位素链的 衰变和自发裂变的半衰期。计算时的基本输入量为两子核的质量数和电荷数以及反应Q 值。GLDM能很好地描述重核和超重核的 衰变和自发裂变过程。计算结果表明,A < 308 时在同位素链上N = 176~184 的区域α衰变为主要衰变模式。A > 308 时在同位素链上自发裂变为主要衰变模式。308122 是α衰变和自发裂变的分界点,暗示着N = 184 为中子幻数。Based on the framework of the Generalized Liquid Droplet Model (GLDM), alpha decay and spontaneous fission half-lives for 292-310122 isotopes are studied. The calculation of the basic inputs which only need the two fragmentmass numbers, charge numbers and the Q value. GLDM can describe alpha decay and spontaneous fission the nuclei. It is found that the alpha decay is the dominant mode of decay for isotopes with mass number A < 308, and for those with A > 308 spontaneous fission is dominant. The demarcation between alpha decay and spontaneous fission is at 308122, which shows the presence of a spherical neutron shell closure at N = 184. 相似文献
16.
Simultaneous determination of trap depth and the ratio of the rate of recombination to that of capture from thermo-luminescence
下载免费PDF全文
![点击此处可从《中国物理》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Thermo-luminescence (TL) is a kind of luminescence decay measured with
varying temperature. In the process of TL the decay parameter itself
involves the temperature effect of traps. Thus the trap depth is inseparable
from the decay parameter. There are two separate peaks in the TL curve of
ZnS:Cu,Co if the measurement starts from liquid nitrogen temperature. In the
experiment we started from zero Celsius temperature to isolate the deeper
traps. We have proposed and realized three methods for simultaneous
determination of trap depth and decay parameter based on the
quasi-equilibrium model and experimental data. If we treat the case of
kinetic order \alpha =1 as \alpha =2, the error might be as large as
100%. 相似文献
17.
Mitra Ghergherehchi Junho Ko Narjes ArabyarMohammadi Hossein Afarideh Yoon Sang Kim 《Pramana》2018,90(3):35
The \(\alpha \) decay half-lives of hyper and normal isotopes of Po nuclei are studied in the present work. The inclusion of \(\Lambda \)–N interaction changes the half-life for \(\alpha \) decay. The theoretical predictions on the \(\alpha \) decay half-lives of normal Po isotopes are compared with experimental results and are seen to be matching well with each other. The neutron shell closure at \(N = 126\) is found to be the same for both normal and hypernuclei. The Geiger–Nuttal (G–N) law for \(\alpha \) decay is unaltered in the case of hypernuclei. The hypernuclei will decay into normal nuclei by mesonic or non-mesonic decay modes. Since the half-lives of normal Po nuclei are well within the experimental limits, our theoretical results suggest experimental verification of the \(\alpha \) emission from hyper Po nuclei in a cascade process. 相似文献
18.
19.
In this work, it is presented an experimental assembly based on electric capture of radionuclides in order to discriminate the alpha activity of 214Po (radon decay product) from 212Po (thoron decay product) one. The alpha activity was registered with CR-39 analyzing etch pit diameters and optical density. This discrimination may allow for the estimation of the relative contribution of the alpha activity due to thoron decay products compared to the total activity due to radon decay products. 相似文献
20.
Tore Berggren 《Hyperfine Interactions》1992,75(1-4):401-408
Starting from the formalism for alpha decay presented by Jackson and Rhoades-Brown /4/ and adapted for the decay of deformed
nuclei by Berggren and Olanders /3/, we calculate half-lives and anisotropies in the alpha decay of oriented odd-mass At isotopes.
The earlier results for harmonic oscillator models are compared to results for a Woods-Saxon model. 相似文献