高级检索

留言板

尊敬的读者、作者、审稿人, 关于本刊的投稿、审稿、编辑和出版的任何问题, 您可以本页添加留言。我们将尽快给您答复。谢谢您的支持!

姓名
邮箱
手机号码
标题
留言内容
验证码

2003年  第20卷  第1期

显示方式:
核物理
核物理中的π介子
李磊, 张小兵, 谭玉红, 宁平治
2003, 20(1): 1-10. doi: 10.11804/NuclPhysRev.20.01.001
摘要:
在强子层次上,原子核或强子物质的基本组元是核子和介子.弄清这些强子的结构,并由基本原理出发研究它们的性质,是当代核物理的重要课题.在各种介子中,π介子是最轻且最重要的介子.关于自由空间中π介子的结构与性质、核介质内π介子的性质、π 核子相互作用与π 核相互作用等问题,始终受到相当多的关注.π介子在核物理中的作用直接联系着手征对称性,汤川秀树关于π介子的最初概念已经大大发展了.有清楚的实验证据表明,核内存在π介子的集体模式,这种集体模式与以前观测到的所有核集体运动模式截然不同.拟对π 核物理的研究现状及值得进一步研究的主要问题予以简要评述. At the hadronic level, nucleons and mesons are constituents of nuclei and hadronic matter. Understanding the structures of hadrons, finding the physics of how the properties of these particles arise from the first principle, are major interests in modern nuclear physics. Among mesons, the lightest and most important one is certainly the pion, thus it is no accident that its structure, properties (both in free space and in nuclear matter) and interactions with nucleons and nuclei have gotten considerable ...
束缚态β-衰变及其天体物理意义
白希祥
2003, 20(1): 11-17. doi: 10.11804/NuclPhysRev.20.01.011
摘要:
束缚态β-衰变是一种特殊的弱相互作用衰变模式,对某些高电离态重原子的β-衰变有重要或决定性的贡献.从理论和实验两方面介绍了束缚态β-衰变研究的进展及其对恒星中的慢中子俘获过程和187Re 187Os宇宙核钟的影响.
利用SLEGS开展夸克和胶子层次上的核物理研究
石宗仁, 徐鹍, 邢雨, 顾嘉辉, 蔡翔舟, 沈文庆
2003, 20(1): 18-25. doi: 10.11804/NuclPhysRev.20.01.018
摘要:
通过对国际上中能核物理的发展,特别是前沿领域中的现状的回顾,阐述了利用在上海原子核所计划建造的第三代同步辐射加速器(SSRF)上建立新一代的激光 电子康普顿背散射γ射线源(SLEGS)从事夸克和胶子层次上的中能核物理研究的科学目标及研究内容. The proposed SLEGS (Shanghai Laser Electron backscattering Gamma Source) will be a circular and linear polarization, new generation, high quality γray source with Eγ=0.2-0.87 GeV. The major scientific focus of nuclear physics research at SLEGS will be investigations of the microscopic quarkgluon aspects of nucleons , nucleon resonance states and nuclei to test and develop nonperturbative QCD. Using polarized photoninduced reactions on unpolarized and polarized nucleon target such as γN→γ N, ...
激发函数中的长程角度关联与量子态叠加
王琦, 董玉川, 李松林, 田文栋, 高辉
2003, 20(1): 26-29. doi: 10.11804/NuclPhysRev.20.01.026
摘要:
在较大的连续角区范围内测量了27Al+27Al耗散反应产物的激发函数,入射束流的能量从114MeV到127MeV,能量步长200keV.分析激发函数的角度关联,角度相干宽度超过40°,各个角度之间反应产物的互关联系数在0.6以上.用宏观条件下的量子态叠加讨论了这种长程角度关联.
160Tb β-衰变纲图研究
孙普男
2003, 20(1): 30-33. doi: 10.11804/NuclPhysRev.20.01.030
摘要:
对由160Tb的β-衰变而产生的γ射线利用GeLi和HpGe探测器进行了单谱和γ γ符合谱的测量.根据单谱和γ-γ符合谱的测量结果给出了160Tb的β-衰变纲图.并用绝热对称转动模型对160Dy中转动带与振动带的耦合参数Zγ值进行了计算,得出从振动带到转动带的γ跃迁几率B(E2)值之比不能通过唯一的Zγ值来描述.Tb/β-衰变;衰变纲图;带耦合参数 The γtransitions in 160Tb decay has been studied by γ ray spectroscopy and γγ coincidence measurements with highefficiency Ge(Li) and HpGe detectors. The β- decay scheme of 160Tb was proposed according to the results of γray spectroscopy and γγ coincidence measurement. The bandmixing parameter Zγ for 160Dy is determined and it is observed that the measured γray branching ratios do not lead to a unique value of Zγ for 160 Dy.
加速器
CSR二极磁铁积分磁场测量系统
熊慧, 何源, 袁平, 韩少斐, 刘维军
2003, 20(1): 34-37. doi: 10.11804/NuclPhysRev.20.01.034
摘要:
介绍了兰州重离子加速器冷却储存环(HIRFL CSR)积分磁场测量系统以及积分测量的基本原理和数据处理方法,对测量结果的分析表明整个系统运行可靠稳定,可用于CSR磁铁的积分测量.This article presents the basic principle of dipole integral magnetic field measurement . The integral coil which has the same radius with the dipole magnets was used to measure the integral magnetic field of different magnets in Cooler Storage Ring(HIRFLCSR). The article also generally introduced the software and hardware systems of the automatic measurement device. According to the repetitive experiments, a suit of better measurement got to be summarized. On the other hand, the article recommends the...
交叉学科
重离子束在诱变育种和分子改造中的应用
卫增泉, 颉红梅, 梁剑平, 袁世斌, 冯岩, 谢忠奎
2003, 20(1): 38-41. doi: 10.11804/NuclPhysRev.20.01.038
摘要:
重离子束具有与中性辐射X,γ和中子不同的特性,利用这些特性开展它在生物学领域内的应用和基础研究具有重要的理论和实际意义.简要阐述了这种应用的理论基础,以及多年来实践的一些工作与取得的结果. Heavy ion beams have different character from X, γ rays and neutrons. It has important value in theory and practice to use the character to carry out application and fundamental researches in biological field. Theoretical basis of the application and some practice and their results are briefly described here.
重离子辐射哺乳动物细胞敏感性的分子机理
李文建, 周光明, 卫增泉, 王菊芳, 李强, 党秉荣, 颉红梅
2003, 20(1): 42-47. doi: 10.11804/NuclPhysRev.20.01.042
摘要:
研究了用传能线密度125.5keV/μm的12C6+辐照小鼠黑色素瘤、中国仓鼠肺、人的宫颈癌、人的肝癌细胞的敏感性以及DNA双链断裂和DNA双链断裂片段分布,结果表明细胞敏感性与DNA双链断裂之间没有一致的关系,提出了细胞辐射敏感性的一种可能的分子机理,即DNA序列敏感性位点协同DNA双链断裂互补性机理.由此解释了4种细胞系的不同敏感性问题. Four types of cells, melanoma B16, cervical squamous carcinima HeLa, Chinese hamster V79 and hepatoma SMMC7721, were irradiated by 125.5 keV/μm carbon ions. Celullar sensitivities to irradiation indicated by D50 , DNA double strand break (DSB) and distribution of DSB fragments expressed by molecular weight are studied. The results show that there is not a consistent relationship between cellular sensitivity and DNA DSB induction, a possible molecular mechanism of radiosensitivity which...
HIRFL辐照终端照射野均匀度与离子通量的关系
李强, 颉红梅, 李文建, 党秉荣, 马秋峰, 卫增泉
2003, 20(1): 48-51. doi: 10.11804/NuclPhysRev.20.01.048
摘要:
采用固体核径迹探测器聚碳酸脂膜,测定了兰州重离子研究装置提供的55MeV/u40Ar和80MeV/u20Ne离子束经辐照终端束流均匀化扫描装置后照射野均匀度与离子通量之间的关系.结果表明:对于40Ar和20Ne离子束,离子通量小于1×106和2×107ions/cm2时,横向照射野均匀度缓Ne离子束照射慢增加;当离子通量分别介于1×106—1×107和2×107—1×108ions/cm2时,40Ar和20野均匀度逐渐增加;离子通量达到1×107和1×108ions/cm2时,40Ar和20Ne离子束照射野均匀度分别约为58%和61%.从而说明,辐照终端束流扫描装置对束流的均匀化程度目前并不能满足辐照生物效应、辐射育种和重离子治癌等研究工作的需要,须对其性能做进一步的提高. Using 55 MeV/u 40Ar and 80 MeV/u20Ne ion beams delivered by the Heavy Ion Research Facility at Lanzhou (HIRFL), the relationships between the irradiation homogeneities in irradiation fields generated by the beam scanning device located at the irradiation terminal of the HIRFL and ion fluence were measured respectively with 100 μm polycarbonate films by means of nuclear track detection. The results show that the homogeneity increases when the ion fluence are lower than ........
DNA双链断裂产额的新算法
周光明, 李文建, 高清祥, 卫增泉
2003, 20(1): 52-54. doi: 10.11804/NuclPhysRev.20.01.052
摘要:
DNA双链断裂(DSB)的定量分析是高传能线密度辐射生物学效应机理研究的重要手段.从实际应用出发,推导了一个新的计算公式———平均分子量法.该法不探究DSB片段的具体分布模式,实际操作中却又包含了片段的含量和分布;而且形式简单、操作简便,尤其适合于荧光扫描数据. Quantitive analysis of DNA doublestrand break (DSB) is of importance for studying on the mechanisms of radiobiological effects induced by high linear energy transfer(LET) irradiation. For the practical use, one new calculating formula named the method of average molecular weight is deducted. In this method, the factual distribution of DSB fragments is not considered, but actually, the content and distribution of DSB fragments are included. Totally, this method is simple in shape and easy to use, esp...
形(应)变超晶格的退道效应与系统的全局分叉
林钧锋, 庄榕榕, 周小方, 王海光, 付丽萍, 罗诗裕
2003, 20(1): 55-60. doi: 10.11804/NuclPhysRev.20.01.055
摘要:
把超晶格"折沟道"对粒子的作用等效为形状相似的弱周期调制.利用正弦平方势把粒子运动方程化为具有外周期弱调制的非线性微分方程,导出了退道系数与晶格畸变的关系.利用多尺度法研究了系统的主共振和子共振,并利用Melnikov方法分析了系统的全局分叉和出现Smale马蹄的临界条件. The effect of deflected channel on particle motion is equivalent to modulation with a weakpotential having a periodic same as the deflected channel has. The motion equation of a particle has been reduced to the nonlinear differential equation with a weakperiodic modulation by using sinesquared potential. The dechanneling fraction has been derived for a strained superlattice. The mainresonance and subresonance have been inverstigated by using multiscale method, a global bifurcation and the critic...
合金溅射轰击诱发的吉布斯偏析现象
郑里平
2003, 20(1): 61-65. doi: 10.11804/NuclPhysRev.20.01.061
摘要:
建立了包括质量效应、键合效应和轰击诱发吉布斯偏析效应的蒙特卡罗模拟程序;并对轰击诱发吉布斯偏析效应的两大特征(表面成分梯度特征和表面成分梯度的中间性特征)进行了研究.模拟解析了为何在被轰击合金表面形成了一个偏析元素的成分梯度;为何被轰击合金表面的成分梯度、溅射角分布和溅射产额具有中间性特征. In 1982, phenomena of bombardmentinduced Gibssian segregation(BIGS) during alloy sputtering were found at low temperature. By using Monte Carlo(MC) simulation programs including mass effect, surface binding energy effect and bombardmentinduced Gibssian segregation effect, we especially study two important characters of BIGS (one is the character of the surface composition gradient of BIGS, and another is the intermediate character of the surface composition gradient of BIGS). The MC simulations give...
用重离子实验数据推算质子翻转截面和轨道翻转率
张庆祥, 侯明东, 刘杰
2003, 20(1): 66-69. doi: 10.11804/NuclPhysRev.20.01.066
摘要:
空间单粒子辐射环境主要由重离子和高能质子构成,但在地面利用两种离子评估器件单粒子效应敏感度成本太高,因此利用重离子实验数据推算质子敏感参数成为一个非常活跃的研究课题.利用Barak经验公式,在重离子实验获得器件的σ LET值曲线的基础上,计算了几种典型器件在不同能量下的质子翻转截面以及典型轨道上质子引起的翻转率,并同FOM方法预示的质子翻转率进行了比较,其结果将对卫星电子系统抗辐射加固设计具有重要参考价值. The radiation environments concerned with single event upset mainly consist of heavy ions from cosmic ray and large flux proton from solar events and planetary radiation belts. The most reliable calculation for SEE rate induced by proton and henvy ions are the way to use the experimentally measured data rospectively. But it is too expensive to test devices with both heavy ions and protons. So it is necessary to derive models for predicting proton crosssections and rates from heavyion test data....