A Faraday Cup Design for High-Current, High-Energy Ion Beams

A high-current, high-energy Faraday cup was designed and built for the Stable Isotope Program at Oak Ridge National Laboratory (ORNL). Faraday cups are commonly utilized in the current characterization of charged particle beams. In ion beam applications, the Faraday cup must be able to mitigate the effects of secondary electron emission (SEE) induced by the positive ions, which can be a challenge as the size, current, and energy of the ion beam increases. ORNL’s Faraday cup is capable of probing high-current (tested up to 100 mA), high-energy (tested up to 45 kV) ion beams up to 10 cm in diameter. However, preliminary testing of the Faraday cup suggest that the effectiveness of its electron suppression system begins to decrease as the ion beam parameters approach the upper tested limits. In this presentation, we will discuss the current capabilities and limitations of the Faraday cup design, and some of the ongoing research efforts to improve this ion beam diagnostic system.