Virtually everything astronomers known about objects outside the solar system is based on the detection of photons—quanta of electromagnetic radiation. Yet there is another form of radiation that permeates the universe: neutrinos. With (as its name implies) no electric charge, and negligible mass, the neutrino interacts with other particles so rarely that a neutrino can cross the entire universe, even traversing substantial aggregations of matter, without being absorbed or even deflected. Neutrinos can thus escape from regions of space where light and other kinds of electromagnetic radiation are blocked by matter. Furthermore, neutrinos carry with them information about the site and circumstances of their production: therefore, the detection of cosmic neutrinos could provide new information about a wide variety of cosmic phenomena and about the history of the universe.
But how can scientists detect a particle that interacts so infrequently with other matter? Twenty-five years passed between Pauli’s hypothesis that the neutrino existed and its actual detection: since then virtually all research with neutrinos has been with neutrinos created artificially in large particle accelerators and studied under neutrino microscopes. But a neutrino telescope, capable of detecting cosmic neutrinos, is difficult to construct. No apparatus can detect neutrinos unless it is extremely massive, because great mass is synonymous with huge numbers of nucleons (neutrons and protons), and the more massive the detector, the greater the probability of one of its nucleon’s reacting with a neutrino. In addition, the apparatus must be sufficiently shielded from the interfering effects of other particles.
Fortunately, a group of astrophysicists has proposed a means of detecting cosmic neutrinos by harnessing the mass of the ocean. Named DUMAND, for Deep Underwater Muon and Neutrino Detector, the project calls for placing an array of light sensors at a depth of five kilometers under the ocean surface. The detecting medium is the seawater itself: when a neutrino interacts with a particle in an atom of seawater, the result is a cascade of electrically charged particles and a flash of light that can be detected by the sensors. The five kilometers of seawater above the sensors will shield them from the interfering effects of other high-energy particles raining down through the atmosphere.
The strongest motivation for the DUMAND project is that it will exploit an important source of information about the universe. The extension of astronomy from visible light to radio waves to x-rays and gamma rays never failed to lead to the discovery of unusual objects such as radio galaxies, quasars, and pulsars. Each of these discoveries came as a surprise. Neutrino astronomy will doubtless bring its own share of surprises.
According to the passage, one of the methods used to establish the properties of neutrinos was
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误选D，海底探测器是用来detect发现cosmic neutrinos，而不是establish the properties of neutrinos研究 C选项定位句since then virtually all research with neutrinos has been with neutrinos created artificially in large particle accelerators and studied under neutrino microscopes. 注意这里的studied
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2021-05-04 11:46:47
我选了D，但仔细看题目的话可以秒选Ｃ； 题目是…was Ｃ是曾经用的方法 D是目前有科学家提出的方法 只能选Ｃ。
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2019-08-12 17:44:01
我觉得不能选D的原因，只能用最后一段第一句来理解，就是project的目的不是为了研究properties，而是提供information about the universe
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2019-01-19 12:12:39
这道题主要是要读题把，文中提到的一个建立中微子属性【性质】的方法是？可以快速得到备选项CD， C——通过对人工制造的中微子的观察【对应since then virtually all research with neutrinos has been with neutrinos created artificially in large particle accelerators and studied under neutrino microscopes】study＝observation D——对于与海水反应的中微子的测量【对应when a neutrino interacts with a particle in an atom of seawater, the result is a cascade of electrically charged particles and a flash of light that can be detected by the sensors.】但是这里讲的只是对中微子的detection，没有讲探测到之后是怎样研究中微子的，所以measurement【测量尺度】是不正确的。
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2018-12-14 18:50:46
xiximei回复xiximei
也可以这样想，人工制造的中微子是用来研究中微子属性的，但是探测到的从宇宙来到地球的中微子是用来研究宇宙信息，而不是中微子本身的属性的。
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2018-12-14 18:52:45
Twenty-five years passed between Pauli’s hypothesis that the neutrino existed and its actual detection: since then virtually all research with neutrinos has been with neutrinos created artificially in large particle accelerators and studied under neutrino microscopes.
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2018-09-25 12:18:19
回头再看看文章，就知道自己为什么一个都没对了。。。加强阅读理解！ 天文学家对太阳系以外物体的了解几乎都是基于对光子电磁辐射的量子化的检测。然而，宇宙中还有另一种辐射形式：中微子。由于（顾名思义）无电荷和可忽略的质量，中微子很少与其他粒子相互作用，以致中微子可以穿越整个宇宙，甚至穿越物质的大量聚集，而不被吸收甚至偏转。因此，中微子可以从光和其他种类的电磁辐射被物质阻挡的空间中逃逸出来。此外，中微子携带关于它们的生产地点和环境的信息：因此，宇宙中微子的探测可以提供关于宇宙现象和宇宙历史的各种各样的新信息。 但是科学家如何才能探测到与其他物质交互作用的粒子呢？Pauli假设中微子存在和实际探测之间已经过去了二十五年：从那时起，几乎所有中微子的研究都是在大粒子加速器中人工制造的中微子，并在中微子显微镜下进行研究。但是一个能够探测宇宙中微子的中微子望远镜很难建造。除非中微子非常大，否则任何仪器都无法探测到中微子，因为大质量就是大量核子（中子和质子）的同义词，而探测器的质量越大，其核子与中微子反应的可能性就越大。此外，该装置必须充分屏蔽其他粒子的干扰效应。 幸运的是，一组天体物理学家提出了一种通过利用海洋质量来探测宇宙中微子的方法。该项目名为DUMAND，用于深海缪子和中微子探测器，该项目要求在海面下5公里的深度放置一组光传感器。检测介质是海水本身：当中微子与海水原子中的粒子相互作用时，结果是带电粒子的级联和由传感器检测到的光闪烁。传感器上方5公里的海水将保护它们免受其他高能粒子通过大气降落的干扰影响。 Dimand项目的最大动力是它将利用一个关于宇宙的重要信息来源。天文学从可见光延伸到无线电波，再延伸到x射线和伽马射线，从未未能导致发现像无线电星系、类星体和脉冲星等不寻常的物体。这些发现都出人意料。中微子天文学无疑会带来它自己的惊喜。
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2018-09-15 16:28:51
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