<正> One set Kicker will be used in the extraction system of CSRm and the required parameters were shown in Table 1. As shown, the kicker will run under a very fast pulse mode. In order to obtain such a fast pulse magnetic field, the inductance of the magnet should be as small as possible. As the inductance of a magnet (Lm) can be calculate like this: Lm = N2 · Am, here N is the turns of the coil, so decreasing the turns of the