• Question: How do you keep the inside of the particle accelerator clean as the images attached show that the scientists are wearing normal clothes meaning there isn't any special super-clean clothing that they have to wear.

    Asked by AbdurRehmanS on 13 Dec 2023.
    • Photo: Joel Goldstein

      Joel Goldstein answered on 13 Dec 2023: last edited 13 Dec 2023 9:48 pm

      The true “insides” of the accelerator are the vacuum pipes in which the beams travel. They are only a cm or two in diameter, running through the centre of the magnets and other components that form the LHC. They have to be clean enough to maintain a good vacuum, so they are rarely opened to the air and only under the clean conditions you are thinking about.

      The rest of the LHC tunnel and even the insides of the experiments do not generally have to be super clean. The only special clothing I have ever had to wear to work at CMS is a hard hat and safety shoes for my own protection.

    • Photo: Daniel Moise

      Daniel Moise answered on 10 Jan 2024:

      The inside of the accelerator is sealed shut. In particular, the tube through which the particles travel (we call it the beam pipe) is kept to a very good vacuum during normal operation. I’m not an accelerator expert, but the collider goes through several stages to get this vacuum up and running. Before running for data taking, we also use special beam configurations designed to get rid of residual particles (we call this scrubbing).
      We do occasionally end up wearing clean clothes. This is a requirement if you’re working with very sensitive components, such as silicon detectors. But this is separate from the day-to-day running of the machine.