With stochastic cooling, measurements of the beam are taken on one side of the ring, and sent across the middle of the ring in time to make adjustments to the AD before the beam comes around the bend from the other side. The antiproton pipe turning a corner. Blue dipole magnets direct the beam, and red quadrupole magnets focus it. Once the beam is refined enough, deceleration begins. This is a somewhat complicated process because, as the beam slows down, it has a tendency to expand.
Scientists decelerate the beam in several steps, interspersing it with more cooling.
Stochastic cooling helps to streamline the beam as it travels through the pipe. A thick, cool cloud of electrons travels in the same direction as the antiprotons, cooling them further. The process is similar to mixing flows of hot and cool water until they are lukewarm. It also helps line up the antiprotons in the direction they're moving. They are delivered in bunches, at about one bunch per minute, with about 10 million antiprotons per bunch.