RF deflecting cavity for fast radioactive ion beams

Abstract

The Facility for Rare Isotope Beams (FRIB) will be a new scientific user facility that produces rare-isotope beams for experiments from the fragmentation of heavy ions at energies of 100–200 MeV/u. During the projectile fragmentation, the rare isotope of interest is produced along with many contaminants that need to be removed before the beam reaches detectors. At FRIB, this is accomplished with a magnetic projectile fragment separator. However, to achieve higher beam purity, in particular for proton-rich rare isotopes, additional purification is necessary. RadiaBeam in collaboration with Michigan State University (MSU) has designed a 20.125 MHz radiofrequency (RF) fragment separator capable of producing a 4 MV kick with 18 cm aperture in order to remove contaminant isotopes based on their time of flight. In this paper, we will discuss the RF and engineering design considerations of this separator cavity.

Acceleration of heavy ions in inverse free electron laser

“…In other words, the ions could be momentarily recaptured by the first harmonic of the RF field due to field distortions. Both of these approaches require using an H-resonator acceleration cavity tank, the dimensions of which grow rapidly for slower beams and quickly exceed those of RFQ in the frequency range of tens of MHz [28].…”

Прототип Протонного Ондуляторного Линейного Ускорителя

“…С точки зрения разработки магнитного ондулятора предпочтительно иметь более длинные периоды, так как максимально достижимые значения магнитного поля пропорциональны периоду ондулятора. Снижение частоты ВЧ-поля позволяет увеличить период, однако со снижением частоты снижается порог ВЧ-пробоя, а реализация низкочастотных резонаторов более громоздкая [19]. На основе этих параметров был разработан дизайн ВЧ-резонатора, отвечающего следующим критериям.…”