Toward a Km-Scale Neutrino Observatory: Digital Instrumentation

9818083Smoot该项目包括开发和建造一串50个数字光学模块，作为南极站冰川冰中下一代中微子探测器阵列的原型。 它由NSF的极地计划办公室，物理学部，天文科学部和数学和物理科学理事会多学科活动办公室共同支持。中微子是由宇宙中能量极高的事件产生的，但与物质的相互作用很弱，因此需要非常大的探测器体积。 当相互作用确实发生时，它会产生可见光范围内的切伦科夫辐射，可以根据光脉冲在冰内不同光学模块的顺序到达时间进行跟踪。 正确分析和识别中微子事件的关键是数据采集，本地信号处理，以及从深层遥感器到表面分析设施的信息传输，这可能涉及几公里的路径长度。模拟光模块的当前阵列具有色散和衰减降低信号质量的缺点。 光纤电缆将保存波形信息，但是成本高并且在模块串的安装期间容易损坏。 这些卫星被冻结在冰层中，深达数公里，无法恢复修复。一串数字光学模块将是坚固可靠的，应能提供高质量的数据，通过精确重建的轨道来描述复杂事件的特征。 全仪器化的弦的运行将是一个具有成本效益的示范，证明在最先进的数字系统架构基础上实施全尺寸中微子望远镜的可行性。

9818083Smoot This project consists of the development and construction of one string of fifty digital optical modules as the prototype for a next-generation neutrino detector array in the glacial ice at South Pole station. It is jointly supported by the NSF's Office of Polar Programs, the Division of Physics, the Division of Astronomical Sciences, and the Office of Multidisciplinary Activities in the Directorate for Mathematics and Physical Sciences. Neutrinos are produced by extremely energetic events in the universe, but interact only weakly with matter and thus require very large detector volumes. When an interaction does occur, it produces Cerenkov radiation in the visible range which can be tracked from the sequential arrival times of the light burst at different optical modules within the ice. Critical to the proper analysis and identification of neutrino events is the data acquisition, local signal processing, and information transfer from deep remote sensors to the surface analysis facility which may involve a path length of several kilometers. The current array of analog optical modules has disadvantages in that dispersion and attenuation degrade the signal quality. Optical fiber cable would preserve waveform information, but is costly and subject to damage during the installation of the module strings. These are frozen in the ice to depths of several kilometers and cannot be recovered for repair.A string of digital optical modules will be robust and reliable, and should provide high quality data from which complex events can be characterized with accurately reconstructed tracks. Operation of the fully instrumented string will be a cost-effective demonstration of the feasibility of implementing a full-scale neutrino telescope based on state-of-the-art digital system architecture.***