Normally, it is impossible to distinguish Cherenkov radiation generated by positrons from that created by electrons.

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These create large amounts of Cherenkov radiation, and can be identified because they trigger several widely spaced detectors.

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The sort of light they are looking for is called Cherenkov radiation.

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Muons created by low-energy neutrinos produce only small amounts of Cherenkov radiation.

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The High-Altitude Water Cherenkov Observatory or Hawc, high on a Mexican plain, now holds the record for the highest-energy light it can capture.

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Current experiments, which were launched in September, include looking for microbes in the upper atmosphere, detecting cosmic rays, and looking for Cherenkov radiation.

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The distribution of the detectors triggered allows the direction of the Cherenkov radiation, and therefore the flight direction of the muon, to be worked out.

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It acts as the medium in which Cherenkov radiation is generated.

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It is these that the "Cherenkov" detectors actually track.

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Cherenkov telescopes such as the Hess array in Namibia or the Magic facility in the Canary Islands catch this process directly from the atmosphere when the particles first arrive at Earth.

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The third layer is called a Cherenkov-radiation detector.

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And muons can generate Cherenkov light.

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