A century after the invention of radio, the oscillating electric fields initially generated for communication now perform a fundamental function in all accelerators.
Instead of being broadcast to the world, radiofrequency (RF) energy at Diamond is trapped in resonating metal cavities to generate the electric fields that bring Diamond’s electrons up to speed.
The journey of an electron from source to storage ring is a tale of high power, split-second timing and frankly terrifying voltages. It begins in the linac gun where energetic, hot electrons are sucked away from a metal cathode by 90,000 volts and directed into the linear accelerator, or linac. The electrons travel down the linac together with precisely timed 16 megawatt blasts of microwaves generated by klystron amplifiers that themselves operate at pulsed voltages in excess of 200,000 volts. Electrons are accelerated towards the speed of light in the linac and then injected into the booster synchrotron where they complete many orbits over a tenth of a second.
Image: The linac, with the gun at the far end and the accelerating structures coming towards us.