Each pipe that you see contains part of the electron beam that has just finished going around the East Arc. Blue electromagnets are used to put the beam back into one pipe so that it can go through the South Linear Accelerator. Notice that the beam in the top pipes gets bent more by the magnets than the beam in the bottom pipes. That's because the more energy the beam has, the harder it is to bend. The electrons in the bottom pipe are on their fifth and final pass through this section, so they have the most energy.