ON THE INELASTICITY OF SUPERHIGH ENERGY COSMIC RAY INTERACTIONS

The inelasticity of p-air and A-air interactions of superhigh energy cosmic rays is analysed and the influence of the nuclear collision geometry is investigated.     

宇宙线高能粒子与液体闪烁体的核相互作用

利用放置在海拔3185米处的多板云室,以液体闪烁体作靶,研究宇宙线高能粒子产生的核相互作用。本文分析了18个由荷电粒子引起的核作用事例,用Castagnoli公式求得初能平均值E₀=(41±8)Bev,荷电粒子平均多重性n_s=4.9±0.3,以x=lgγ_ctgθ_l为变量作次级粒子的角分布,发现dN/dx分布可能存在着两个峯,文中试用二心模型对此角分布进行了讨论。 关键词：     

高能宇宙线粒子与石蜡核作用的角分布

本文描述一个利用云室研究高能宇宙线粒子与石蜡的核作用中次级粒子角分布的实验。共分析了64个n_s≥4的事例,其平均初能E₀≈70BeV。结果表明,在此能区,次级粒子在CMS中,角分布不是各向同性,而在0°和180°方向呈现极大,且有相当比例(≥20％)事例的角分布形式显示出火球模型给出图象。     

AN EXPLANATION TO THE INCONSISTENT PHENOMENON BETWEEN MEAN MULTIPLICITY AND AVERAGE TRANSVERSE MOMENTUM IN COSMIC RAY EXPERIMENTS WITH SUPERHIGH ENERGY OF E > 1015 eV

The rapid increase of both and T> as S increases in superhigh energy cosmic ray experiments manifests some inconsistencies with the 1> ≤ π/4 S^1/2 rule. It is shown that these inconsistencies can be weakened with the assumption that only the secondary particles of the small fireballs are measured in the Ashtonsr experiment ^[3], but still not removed.     

RESEARCH FOR THE POSSIBILITY ON DETECTING COSMIC RAY PARTICLES BY ACOUSTIC WAY

The exploring results of the possibility on detecting cosmic ray particles by acoustic way are reported. It shows that the ultrasonic background noise is very complicated and there are some individual and transient ultrasonic signals in the natural wide water. The mechanism producing these signals may be the sound radiation of the microbubbles in water. There is no evidence for the possible correlation between these signals and cosmic ray particles. The threshold energy of acoustic detection of EAS core is above 3﹒10¹⁶eV at sealevel and the threshold energy of acoustic detection of the local showers produced by cosmic ray particles is above 10¹⁴eV     

宇宙线天体物理中的几个重要问题

宇宙线是来自宇宙空间的高能粒子流，研究宇宙线的起源、加速、传播机制及其所涉及的天体物理和宇宙学过程是宇宙线天体物理研究的重要内容。本文介绍并讨论其中几个涉及物理学一些基本问题的重要课题的研究现状及前景，其中包括极高能宇宙线的观测研究，太阳中微子能谱的实时测量，宇宙线中新粒子的搜寻等。     

宇宙线天体物理研究进展

由于天体粒子物理涉及的研究领域太宽,本文拟以宇宙线总的能谱特征为线索,分段介绍各能区的研究前沿,总结有关宇宙线的起源、传播和成分的理论模型和相应的观测实验进展,并简要介绍相关的高能领域,例如γ暴(GRB),中微子,暗物质,超对称(SUSY),大统一理论(GUT)。这些理论在某种程度上暗示着极高能宇宙线的产生机制,并可能意味着需要新的超出标准粒子物理模型的理论来解释GZK截断(GZK Cutoff)的疑难问题。对高能天体物理的研究可以拓宽人类对早期宇宙的认识,为新物理理论模型提供检验的证据,为人类认识自然提供了另一扇窗口。     

腔靶离子发射特性实验

在ICF总体实验中,用法拉第杯首次测量了腔靶离子飞行时间谱,相应得到飞行速度谱,进而得到腔靶内爆区的快离子特性。实验表明,腔靶等离子体从飞散速度上分三四群,不象平面靶分快慢两群。同时确认在间接驱动靶内爆区存在着从源区进入的速度高达10~8cm/s的快离子,对高效爆聚具有破坏性。     

MEASUREMENT OF HEAVY PARTICLE MASS DISTRIBUTION IN COSMIC RAY AT SEA-LEVEL

The apparatus consisting of two time of flight systems and absorber and its performences are described. This apparatus has been used to measure heavy particle (p, d, and α) mass distribution in cosmic ray at sea-level, and the results compared with other works are given.     

OUTER DRIFT CHAMBER FOR PEP-4 EXPERIMENT AND COSMIC RAY TEST

The function, the structure and the cosmic ray test of the outer drift chamber for PEP-4 Experiment at SLAC are described.     

用光学信息量定量评价散乱射线对x射线照相底片的影响

文章介绍了用光学信息论的熵方法，在固定条件下，通过定量计算同一被摄物，在散乱射线不同的情况下，ｘ射线照相底片的信息量。而有效地评价散乱射线对底片象质影响。     

A TRIGGER SCHEME FOR COSMIC RAY EXPERIMENT WITH A SAMPLE-AND-HOLD SYSTEM

This paper presents a trigger scheme which has been used in a cosmic ray experiment with a sample-hold readout system.The experiment shows that this trigger scheme can fully collect the whole output signals of the wire chamber for the random cosmic ray events and get rid of the problem of signal loss caused by the delay of sampling gate.Some disscussions about using this scheme for cosmic ray test of BES are also provided.     

利用Matlab GUI实现光学信息处理教学实验的动态模拟

以“空间频谱的观察与分析”和“空间滤波”两个实验为例,利用Matlab及其图形用户界面(GUI)模块设计模拟实验,实现光学信息处理教学实验的动态模拟,不仅可以方便地在课堂上进行演示,使演示实验与理论讲解能够灵活地穿插进行,而且能通过现场调节实验参数、动态显示实验结果、分析实验参数影响等环节加深学生对相关概念和原理的理解,对提高光学信息处理课程的教学效果起到很好的辅助作用.     

MEASUREMENT OF THE ENERGY SPECTRUM OF PRIMARY COSMIC PAYS

The method and arrangement determining the energy spectrum of primary cosmic rays by measuring the Cerenkov radiation were described. The integral power index γ=1.80±0.11 of energy spectrum of primary cosmic rays wa measured at the energy range of 2.9×10¹⁴－4.0×10¹⁵eV.     

SIMULATION CALCULATION FOR DETECTION EFFICIENCY IN THE MEASUREMENT OF COSMIC RAY HADRON SPECTRA

Using CKP model and the results from accelator experiments, the efficiency of a hadron detector, consiststing of Pb-target and G-M counters, is simulated. The simulation technique for CKP model is discussed.     

在物理实验中变验证性实验为研究性实验

以塞曼效应为例,通过思考题的形式引导学生根据实验目的,对实验内容进行思考分析,设计出实验方案,并将实验方案在实验室中得以实施和优化,将传统的验证性实验变成了研究性实验。通过实验使同学们牢固地掌握了所学内容,对相关仪器设备的性能和使用有了更深入的理解,有效地培养了他们的创新意识和能力。     

平均能量为2×1015eV的宇宙线入射方向研究

从1982年5月到1983年1月,悉尼大学的小型宇宙线观测阵列记录了多于17,000个能量为6×10¹⁴—5×10¹⁶eV的宇宙线广延大气簇射事例。使用谐波分析和X²检验法,对这些宇宙线的入射方向进行了研究,没有发现有意义的各向不同性。 关键词：     

THE NEGATIVE-POSITIVE RATIO OF CHARGED COSMIC RAY HADRONS AT THE 3220 m ABOVE SEA-LEVEL

Single tracks of unaccompanÏed charged hadrons, within a horigontal area of 0.23m² have been measured with a magnetic spectrometer, a pre-selector of momentum in combination with a multiplate cloud chamber in a laboratory at 3220m above sea level. Taking various possible corrections into account, the negative-positive ratio of charged hadrons was obtained as N^-/N⁺=0.53±0.05 in the momentum range of 10-20 GeV/c. If we considered N⁺ contained only P and π⁺, N^-were π^-and that N_π+/N_π-=1, we deduced the result N_π-/N_p=0.9±0.1. Taking the form of the π^-integral spectrum as j（>p）=Kp^-γ, it was estimated that γ（?）2.3 in the momentum range 5—20 GeV/c. In this paper the integral verticel flux intensity of all charged hadrons was also estimated roughly, the result is:j_⊥^p+π（>12 GeV/c）=（7.4±0.7）×10^-5/cm²·sг·s_^.     

大气层外核爆炸X－射线辐射场特性研究

Ｘ射线被认为是大气层外反导栏截武器的主要破坏因素。在航天器结构材料的辐射损伤计算中，需要核爆炸Ｘ射线辐射场的数学模式。从Ｐｌａｎｃｋ黑体谱出发，提出按温度梯度分层的归一化黑体谱组合模式，给出Ｘ－射线的释放能量及辐射脉冲，从而建立了大气层外核栏截Ｘ－射线辐射场特性的数学模式     

由宇宙线(1011—1014电子伏)引起的高能核作用

这篇总结性文章叙论了由能量高到10¹¹—10¹⁴电子伏的粒子在乳胶和云室中所引起的高能核作用。文中首先提出和讨论了在测量上较困难的一些问题,例如,初能量的测量,次粒子的辨认和靶质量的估计。一些可能揭示碰撞机构从而显示核子内部结构的物理量的物理意义,也适当地加以讨论和阐明。除了不同次粒子的多重性外,主要的物理量是:次粒子的角分布、它们的横动量和非弹性系数。关于这些量的测量原理,实验准确度和实验结果的物理意义,特别是后面一点,都有了较充分的检查和讨论。末了,“一个发射中心”和两个发射中心”的各种模型也从物理观点作了较定性的描述和讨论,并和实验结果作了比较。希望通过这篇文章对高能核作用目前发展的概况、尚存在的问题及今后工作的方向能有一定的了解。