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arXiv 1104.2403astro-ph.IM
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1960年代Cosmic-ray阵雨的难以捉摸的无线电和光发射的探测

Detection of elusive Radio and Optical emission from Cosmic-ray showers in the 1960s

David J. Fegan

摘要:

在20世纪60年代,一个小型但充满活力的宇宙射线物理学家社区,开创了探测地球大气层中广泛空气簇射(EAS)的新光学方法,其主要目标是寻找高能宇宙伽马射线的点源。在这十年中,进展极为缓慢。由于当时使用的是相当原始的光收集系统,加上实际上无法拒绝强子簇射产生的压倒性背景,因此试图将簇射的光学切伦科夫辐射作为TeV伽马射线天文学的基础是困难和有问题的。与此同时,一些研究小组也在尝试对EAS的无线电辐射进行被动探测,作为一种可能的廉价、简单、独立的方法来探测和消除能量大于10^16 eV的簇射。到了1990年代末,无线电辐射被高度波束化,因此探测高能簇射的有效收集区域非常有限,降低了无线电特征作为独立簇射探测通道的有效性。到20世纪70年代初,人们对光学和无线电技术的早期乐观情绪开始消散,大大减少了研究活动。然而,经过长期的中断,这两条途径都及时恢复了,光学在20世纪80年代初,无线电在21世纪初。随着数字逻辑硬件的出现,强大的低成本计算,执行蒙特卡罗模拟的能力,以及最重要的是,大大改善了资金,快速发展成为可能。随着时间的推移,这项工作被证明是高能伽马射线天文学和中微子天体物理学的基础。在这里,第一个十年的实验研究在这两个领域进行审查。

英文摘要:

During the 1960s, a small but vibrant community of cosmic ray physicists, pioneered novel optical methods of detecting extensive air showers (EAS) in the Earth's atmosphere with the prime objective of searching for point sources of energetic cosmic gamma-rays. Throughout that decade, progress was extremely slow. Attempts to use the emission of optical Cherenkov radiation from showers as a basis for TeV gamma-ray astronomy proved difficult and problematical, given the rather primitive light-collecting systems in use at the time, coupled with a practical inability to reject the overwhelming background arising from hadronic showers. Simultaneously, a number of groups experimented with passive detection of radio emission from EAS as a possible cheap, simple, stand-alone method to detect and characterise showers of energy greater than 10^16 eV. By the end of the decade, it was shown that the radio emission was quite highly beamed and hence the effective collection area for detection of high energy showers was quite limited, diminishing the effectiveness of the radio signature as a stand-alone shower detection channel. By the early 1970s much of the early optimism for both the optical and radio techniques was beginning to dissipate, greatly reducing research activity. However, following a long hiatus both avenues were in time revived, the optical in the early 1980s and the radio in the early 2000s. With the advent of digital logic hardware, powerful low-cost computing, the ability to perform Monte Carlo simulations and above all, greatly improved funding, rapid progress became possible. In time this work proved to be fundamental to both High Energy Gamma-ray Astronomy and Neutrino Astrophysics. Here, that first decade of experimental investigation in both fields is reviewed.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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