A fast profile monitor for intense ion beams.

Abstract

We present a Faraday Cup Array (FCA) beam profile monitor designed for rapid monitoring of high-intensity direct current ion beams. The monitor consists of 2112 small Faraday cups (FCs) arranged uniformly in a grid pattern over an area of 89.2 × 89.2 mm2. These FCs are arranged in rows and columns, forming 64 independent channels, which are evenly split into 32 x-channels and 32 y-channels, with each channel comprising 33 FCs. Each channel is connected to an independent channel of a 64-channel picoammeter, allowing all channels to conduct current measurements simultaneously and independently. The monitor is capable of directly detecting the projections of beam current distribution in both horizontal and vertical directions with a spatial resolution of 2.75 mm within 1 s. We tested it using He2+ beams with energies of 120 and 200 keV, corresponding to beam powers of 15 and 27.5 W, respectively. The temperature increases on its front and back sides were monitored during the test. We also studied the thermal conduction and temperature rise through simulations when it was exposed to ion beams.