Simulation and test of beam angle monitor for pulsed high current

Beam monitors sensitive to the beams azimuthal B-dot field (sometimes referred as B-dots) are widely used to measure the displacement of beam centroid, as the beam generates a dipole term of the azimuthal magnetic field. Basing on the principle of the proportionality between the deflection angle and the difference of axial B field between the axially symmetrical positions, the axial B-dot probe has a potential use for beam deflection angle measurement. A calibration stand was built to test and improve the beam angle monitor, which was fabricated as a PCB structure. Meanwhile, simulations using the CST MWS codes were performed, demonstrating a good agreement with test results and giving some advices to suppress the disturbance of position deviation of the beam. Both the simulations and the experiments show that the axial B-dot monitor can be successfully used to measure the beam tilt directly.