Study of Extremely High Energy Hadron Interactions by means of Pamir Cosmic-Ray Experiments.

通过在帕米尔高原（4200m）暴露的厚铅x射线室（60cm Pb）中观测宇宙射线族和单到达强子，研究了超高能强子相互作用的特征。约3000平方米的x光片已从莫斯科国立大学全部处理后送到早稻田大学。宇宙射线总曝光量为57 m^2年，每10m^2有5个单位室。主要研究结果总结如下：总共发现并测量了57个可见能量不低于100 TeV的宇宙射线族。在帕米尔海拔（595 g/cm^2），分别用4623和3097的总统计量得到了单到达的可见能量大于4 TeV的强子和伽马射线的能谱和通量。结果表明，在原宇宙正常化学成分假设的基础上，两族强子和单到达强子的通量都远小于模拟计算所期望的5倍或更多，在CERN对撞机能量为-100TeV之前，证实了更多的ys和普通型强子相互作用。测量了高能强子通过铅的衰减平均自由程，得到了与强子相互作用几何截面一致的值，λ (att) =215(]SY+-[)30g/cm<@D12@>D1。而在不低于700 TeV的17个可见能超族中，140高能强子（bbb10 TeV）的平均自由程衰减较小。1 (att) =170+47-26g/cm<@D12@>D1。这些结果似乎表明，强子相互作用的特征可能会在比目前的加速器实验高得多的能量下发生变化。发现有几种高能强子相互作用在腔室材料中表现出异常跃迁行为，这是在普通强子相互作用的基础上进行模拟计算所没有的。为了研究铅在不同靶材料中强子相互作用的异常特征，我们从帕米尔向早稻田发送了带有两层碳靶的新腔室的x射线胶片，开始了分析，完成了96 m^2年总曝光量的一半左右。报告将在不久的将来提出。少

The characteristics of extremely high energy hadron interactions is studied through observation of cosmic-ray families and singly arrived hadrons with thick lead x-ray chambers (60cm of Pb) exposed at Pamir altitudes (4200m). X-ray filmes about 3000 m2 have been to sent to Waseda University from Noscow State University after full processings. The total cosmic-ray exposures amount to 57 m^2year with 5 unit chambers of each 10m^2. The main results are summarized as follows.In total 57 cosmic-ray families of visible energy not less than 100 TeV are found and measured. Energy spectra and flux of singly arrived hadrons and gamma-rays of visible energy greater than 4 TeV are obtained by total statistice of 4623 and 3097, respectively, at Pamir altitude (595 g/cm^2). It was found that the fluxes of both families and singly arrived hadrons are far less, about factor 5 or more, than expected from simulation calculations based on the assumption of normal chemical composition of primary cosmic-ra … More ys and ordinary type hadron interactions confirmed upto the CERN collider energy of -100TeV.The attenuation mean free path of high energy hadrons through lead is measured and it gives the consistent balue with geometrical cross section for the hadron interactions, lambda (att) =215(]SY+-[)30g/cm<@D12@>D1 for lead. However, 140high energy hadrons (>10 TeV) in 17 super families of visible energy not less than 700 TeV shows smaller attenuation mean free path. 1 (att) =170+47-26g/cm<@D12@>D1. Such results seems to indicate characteristics of hadron interactions might be changed at much higher energies than the present accelreator experiments.It was found there are several high energy hadron interactions which show abnormal transition behavior through chamber materials, which are never seen in simulation calculation on the basis of ordinary type hadron interactions. In order to study such abnormal characteristics of hadron interactions in different target materials from lead, X-ray films of new chambers with two storyed carbon target have been sent to Waseda from Pamir and the analysis has started and about half of total 96 m^2year exposure have been completed. The report will be presented in near future. Less