• Warl0k3@lemmy.world
    link
    fedilink
    arrow-up
    64
    ·
    edit-2
    1 month ago

    The probability of interaction between a nuclei and a particle is called a “barn” - because its a bit like shooting the broad side of a barn.

    Its a standard Sci unit, too, so real actual papers will use “megabarn” as a real unit of measure.

    Its subunit is called a “shed”, because physicists don’t get out enough.

    • mkwt@lemmy.world
      link
      fedilink
      arrow-up
      8
      ·
      1 month ago

      Barns have physical dimensions of area, even though they are used to express probability distributions. So you can imagine “the broad side of a barn” as being so many square meters, but then scale it way way down to a particle physics equivalent, and you get the barn. Which apparently roughly represents “the broad side of a uranium nucleus”.

      • 2nd_Fermenter@lemmy.world
        link
        fedilink
        arrow-up
        2
        ·
        28 days ago

        I actually like the barn as a unit of measure.

        I am forever haunted by the decision decades ago to refer to two of the quarks as Top and Bottom. Maybe it was cute at the time. It did not age well.