Study and improvements of a radially coupled coaxial Fast Faraday cup design toward lower intensity beams

A radially coupled coaxial fast Faraday cup design was presented in Carneiro et al. [Int. J. Mod. Phys. A 34(36), 1942013 (2019)] for high-intensity non-relativistic proton beams. In this work, we discuss a modification of that design in the context of a relatively lower intensity ion beam for longitudinal charge profile measurements. Particle-in-cell and time domain electromagnetic simulations of the new design with a focus on avoiding field dilution while generating enough signal for relatively lower intensity ion beams at the upcoming High Current Injector Program at the Inter-University Accelerator Center, New Delhi [A. Roy, Curr. Sci. 76(2), 149–153 (1999); Kanjilal et al., in 3rd Asian Particle Accelerator Conference (Pohang Accelerator Laboratory, 2004), p. 73], is discussed. Profile distortions from secondary electron emission are estimated, and strategies to suppress them are discussed.