Magnetic field sensors applied to electropolishing of superconducting RF TESLA-type cavities

In this work an electromagnetic non-invasive and contact-less technique using Flux-Gate first-order gradiometer is proposed to detect the magnetic field distribution during electropolishing of copper surface. The electropolishing of the copper surface employed in superconducting RF TESLA-type cavities has been monitored using magnetic field sensors. Local information regarding the dissolved copper surface during the electropolishing process has been obtained. An electromagnetic inversion of the magnetic field imaging have been implemented to better understand the effect of the cathode geometry on the electropolishing process.