Windowless gas dynamic ion beam cooler and buncher

Abstract

In this paper the concept of the windowless gas dynamic ion beams cooler and buncher is proposed. This ion beam cooler/buncher has a very simple design, it is ultra-compact having a total length of only 20 cm including the extremely small-sized RF-buncher of 18 mm length. It consists of diverging supersonic nozzle having the inner tube on the axis that allows direct injection of primary ion beam into supersonic carrier gas jet and three simple differentially pumped RF funnels connected through the small diverging nozzles. In the new design there is no need for big and highly expensive vacuum pumps for maintaining the required vacuum levels around the cooler.The realization of this cooler/buncher concept will allow the fast and highly efficient deceleration, cooling and bunching ion beams with primary energies up to 300 keV without the need for high-voltage platforms. The feasibility of this concept for production of high-quality continuous and pulsed ion beams in wide range of masses and having a very small transverse and longitudinal emittance is demonstrated by results of detailed gas dynamic and ion-trajectory simulations which are presented and discussed.