Magnetic Field Measurement and Analysis of Thin Septum for Diffraction Limited Storage Ring

Fast kickers such as strip-lines along with lambertson magnet or thin septum magnet could support onaxis injection for Diffraction Limited Storage Ring (DLSR), in which traditional off-axis injection becomes inadequate. This paper focuses on the theoretical simulation and field measurement of thin septum magnet. The scheme of eddy-current type thin septum magnet (the thinnest portion is with the thickness of 0.9mm) was adopted with laminated silicon steel sheets as magnet core. The simulation of main field and leakage field along the beam trajectory, the stray field decayed over 1millisecond time had been carried out within Opera 2D/3D. Field measurement and analysis of thin septum magnet also has been conducted comprehensively. The results meet requirement that the integral leakage field is less than 0.1% with respect to the main one. The work laid a foundation for injection technology of advanced light source.