Application of carbon nanotube wire for beam profile measurement of negative hydrogen ion beam

A wire-scanner monitor (WSM) using metallic wire is reliably employed for the beam-profile measurement. Because the loading of negative hydrogen (H⁻) ion beam on a wire increases under high-current beam operation, we focus on using a high-durability beam profile monitors by attaching another wire material. Carbon nanotube (CNT) has a tensile strength not less than 100 times that of steel. The electric conductivity has higher than that of metals, and hardness is endured thermally around 3000 °C in a vacuum circumstance. We applied the CNT wire to WSM and measured transverse profiles with a 3-MeV H⁻ beam. As a result, we obtained the equivalent signal levels taken by carbon fiber made of polyacrylonitrile without significant damage. The signal response, the beam profile and the surface observation were discussed in this paper. (paper)