Radio waves detected from individual electrons

Science : Charged particles traveling through magnetic fields are deflected from their linear paths and instead follow curved trajectories. In doing so, they release radiation. For the first time, researchers have detected the radio waves of a single electron trapped in a spiral in a strong magnetic field. To achieve this, a team of scientists at the University of Washington in Seattle trapped krypton-83 gas produced by the decay of rubidium-83. When trapped, each krypton atom ejected a single electron with a known energy. The electrons were piped into a waveguide cell in the presence of a superconducting magnet. The waveguide was designed to detect electromagnetic radiation between 25 GHz and 27 GHz and transmit the radiation to amplifiers. That allowed the researchers to track the change in frequency of the emissions of individual electrons as they lost energy and spiraled inward. The technique provides researchers with a new method for measuring the energy of electrons in a nondestructive manner. It may also be useful for calculating the mass of neutrinos by using electrons emitted from tritium atoms via beta decay .