Superconducting Radiofrequency (SRF) Accelerator Cavities
I’m Charlie Reese. An Accelerator Technology Scientist here at Jefferson Lab. We use SRF cavities as an important part of our work. SRF stands for Superconducting Radiofrequency. Superconducting Radiofrequency cavities are very similar, I like to say, to organ pipes. Except that we use radio waves that resonate inside of the structure Rather than air pressure waves as one would with a musical instrument. We use this in order to accelerate the particle beam in a very efficient way. In use, I have an example cavity here that’s been cut in half So that you can see inside. In use, we build up electric and magnetic fields Resonating at one and a half billion times a second. An electron beam comes through. It sees an electric field that kicks Gets a kick each time it passes through a cell. An SRF cavity of this style is made of niobium. Because niobium, when it sits in a liquid helium bath About 2 Kelvin, Becomes superconducting, so that we can create About 14 million volts between this point and this point While making only about 30 watts of heat. So it’s a very efficient way To accelerate the electron beam Without wasting energy. SRF cavities are very important for our work at Jefferson Lab.