Boundary element method reconstruction of two‐dimensional magnetic‐field maps from measured boundary data in accelerator magnets

Rotating-coil magnetometers are standard devices for measuring integrated magnetic fields of accelerator magnets.The coil intercepts the magnetic flux at a radius given by the dimensions of the measurement shaft that comprises a set ofinduction coils. For magnets of a rectangular aperture with a large aspect ratio (larger than 3:1) the cylindrical domain will coveronly a portion of the magnet aperture. We, therefore, explore an alternative sampling technique using boundary data acquiredfrom a displaced stretched-wire or from a translating fluxmeter. The method presented in this study concerns the reconstructionof the two-dimensional map of the integrated magnetic field distribution in the entire magnet aperture using the measuredboundary data.