Electromagnetic radiation is strongly absorbed by a magnetized plasma if the radiation frequency equals the cyclotron frequency of plasma electrons. It is demonstrated that absorption can be completely canceled in the presence of a magnetostatic field of an undulator, or a second radiation beam, resulting in plasma transparency at the cyclotron frequency. This effect is reminiscent of the elect...

Noli turbare circulos meos—do not disturb my circles—was the final wish of Archimedes, who demanded that Roman soldiers not destroy the perfect circular forms he had drawn on the ground. The literal opposite is true for a team of researchers who have designed a new way to accurately measure the tiny shifts in an electron’s circular orbit as the particle moves in a magnetic field. The experiment...

Thick targets of carbon, aluminum, copper, and tantalum were each bombarded with beams of protons, deuterons, ex-particles, and carbon ions. The target station was 5.5 m from an 80 cm thick ordinary concrete shield wall. Measurements were made of radiation levels of fast neutrons, thermal neutrons, and y-radiation on the shielded side of the wall for each target-beam combination. Total radiatio...

For safe and reliable operation of commercial radioisotope production medical cyclotrons the implementation of preventative maintenance at regular intervals becomes mandatory. During the long-term operation of a medical cyclotron, numerous (radio) activated zones at various locations of the cyclotron facility producing high levels of gamma radiation are created. These radioactive zones are caus...

Cyclotrons are used in medical applications mostly for radioisotope production for positron emission tomography (PET) and proton therapy. PET is a diagnostic technique requiring daily production of radiotracers. Most of the PET cyclotron centres produce 18F for the synthesis of fl uorodeoxyglucose (FDG). The cyclotron laboratory in Bern is a part of the SWAN project aiming at the realization of...