The modern picture of the neutrino as a multiple-mass, highly mixed neutral particle has emerged over forty years of study. Best known of the issues leading to this picture was the apparent loss of neutrinos coming from the sun. This article describes another piece of evidence that supports the picture; the substantial reduction of high-energy muon-type neutrinos observed in nature. For much of the forty-year period before the modern picture emerged, this observation was known as the “atmospheric neutrino anomaly,” since these neutrinos originate in the Earth’s atmosphere. This paper describes the discovery of the atmospheric neutrino anomaly. I explore the scientific context and motivations in the late 1970s, from which this work emerged. The gradual awareness that the observations of atmospheric neutrinos were not as expected took place in the 1983–1986 period.

中文翻译：

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“异常”大气中微子事件的历史：第一人称叙述

中微子作为一种多质量、高度混合的中性粒子的现代图景已​​经在四十年的研究中出现。导致这张照片的最著名的问题是来自太阳的中微子的明显损失。这篇文章描述了另一个支持图片的证据；在自然界中观察到的高能μ子型中微子的大量减少。在现代图像出现之前的四十年的大部分时间里，这种观测被称为“大气中微子异常”，因为这些中微子起源于地球大气层。本文描述了大气中微子异常的发现。我探索了 1970 年代后期的科学背景和动机，由此产生了这项工作。