Magnetic field correction of the IFUSP RTM booster-end magnets

We present the magnetic field correction of the 5.1 MeV IFUSP race-track microtron booster-end magnets, the second stage of the 31 MeV cw electron accelerator under construction. The correction of the magnetic field was done attaching to the pole faces, coils made of etched printed circuit whose copper leads are shaped like the lines of equal magnetic field of the uncorrected magnet. This method of correction assured uniformity of few parts in 105 in an average field of 0.1 T, over an area of 700 cm2.