The effects of Earth's magnetic field on 3-inch diameter photomultipliers used in KM3NeT neutrino telescope
The effects of Earth's magnetic field on 3-inch diameter photomultipliers used in KM3NeT neutrino telescope
复制标题
地球磁场对KM3NeT中微子望远镜使用的3英寸直径光电倍增管的影响
DOI：
10.1051/epjconf/201611601005
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发表时间：
2016
期刊：
影响因子：
--
通讯作者：
N. Randazzo
中科院分区：
文献类型：
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作者：
V. Giordano;S. Aiello;E. Leonora;N. Randazzo
KM3NeT中微子望远镜将是最大的水下中微子望远镜，将位于地中海的深渊。在中微子望远镜中，探测器的关键元件是光学模块，对于KM3NeT，它由31个pmt组成，存储在一个17英寸的透明耐压玻璃球中，在确保良好的透光性的同时起到机械保护作用。由于安装在水下中微子望远镜中的pmt会因海流引起探测器结构的运动而改变方向，因此研究了地球磁场的影响。利用金属笼的磁屏蔽来减少磁效应，使PMT的响应与方向完全无关。为了量化对磁场的影响，我们比较了3英寸PMT在3个PMT倾斜的屏蔽和非屏蔽条件下的增益变化、传输时间扩展和检测效率。数据显示，变化是足够低的，特别是对于时序特性。
The KM3NeT neutrino telescope will be the largest underwater neutrino telescope and will be located in the abyss of the Mediterranean Sea. In neutrino telescopes the key element of the detector is the optical module and for KM3NeT it consists of 31 PMTs stored inside a transparent pressure-resistant glass sphere of 17-inch that serves as mechanical protection while ensuring good light transmission. Since the PMTs installed into an underwater neutrino telescope can change their orientation because of movements of the detector structure due to sea currents, the influence of Earth's magnetic field has been investigated. Magnetic shielding by means of a mu-metal cage is used to reduce magnetic effects and to make the response of the PMT sufficiently orientation independent. In order to quantify the effect on magnetic field, we compared measurements on variation of gain, transit time spread and detection efficiency for a 3-inch PMT in shielded and unshielded condition at 3 PMT inclinations. Data shows that variations are sufficiently low especially for timing properties.