11 votes

Scientists piece together the largest U.S.-based dark matter experiment

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  1. moriarty
    (edited )
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    Wow, this is fascinating. I wish they added a few more paragraphs about how they expect to detect WIMPs rather than the technical details of how precisely the detector is built. WIMPs, unlike...

    Wow, this is fascinating. I wish they added a few more paragraphs about how they expect to detect WIMPs rather than the technical details of how precisely the detector is built. WIMPs, unlike previous standard model particles, are a total mystery in that we have no idea how they interact or what kind of signature they leave (or even if a large enough amount of them travels through space). From what I could piece together, they're modeling this detector after other neutrino detectors like the super-K in Japan and IceCube in Antarctica. The reason for this is because they expect a weakly interacting particle like the neutrino. For these kind of particles that barely leave any kind of signature (they travel freely through the Earth for example) one way to observe them is through Cherenkov radiation. As charged particles travel into thick mediums like water (or xenon in this case) at speeds higher than speed of light in that medium, they radiate photons. We're talking about a really tiny amount of photons, that are then picked up by the surrounding photomultiplier tubes to create a signal. You can even sketch a really rough track of that particle through the medium. I have no idea how they're going to separate that signal from neutrino signal, but one can take advantage of their wildly different masses perhaps.

    3 votes
  2. mb3077
    Link

    LZ is particularly focused on finding a type of theoretical particle called a weakly interacting massive particle or WIMP by triggering a unique sequence of light and electrical signals in a tank filled with 10 metric tons of highly purified liquid xenon, which is among Earth's rarest elements. The properties of xenon atoms allow them to produce light in certain particle interactions.

    2 votes