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

本文通过在帕米尔高原（4200米）用厚铅X射线室（铅厚60厘米）观测宇宙线族和单到达强子，研究了极高能强子相互作用的特征。约3000平方米的X光胶片已从莫斯科州立大学送往早稻田大学，经过全面处理。宇宙射线总照射量为57平方米/年，5个单位室，每个10平方米。主要结果如下：共发现并测量到57个可见光能量不低于100 TeV的宇宙线族。在帕米尔海拔595 g/cm ^2处，用总统计量分别为4623和3097的方法，获得了单个到达的可见能量大于4 TeV的强子和γ射线的能谱和通量。结果表明，两族强子和单个到达强子的通量都远小于基于原初宇宙核正常化学组成假设的模拟计算结果，约为5倍或5倍以上。 ...更多信息 测量了高能强子通过铅的衰减平均自由程，给出了与强子相互作用几何截面一致的公式：铅的λ（att）=215（]SY+-[）30 g/cm<@D12@> D_1.而能量不低于700 TeV的17个超族中的140个高能强子（>10 TeV）的衰减平均自由程较小，1（att）=170+47- 26 g/cm<@D12@> D_1。这些结果似乎表明，在比现有加速器实验能量高得多的能量下，强子相互作用的特性可能会发生变化，并发现有几种高能强子相互作用在通过腔室材料时表现出异常的跃迁行为，这是在基于普通型强子相互作用的模拟计算中从未见到过的。为了研究铅在不同靶材料中强子相互作用的这种异常特征，装有双层碳靶的新室的X射线胶片已从帕米尔送到早稻田，并已开始分析，已完成了96 m^2年总曝光量的一半左右。报告将在不久的将来提交。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