Research of reproducibility of dipoles for cooler-storage-ring

The measurement method and principle of dipole magnet reproducibility for cooling-storage-ring are introduced. The effects of position and number of steel sheet on the reproducibility of magnet is investigated. The measurements indicate that the reproducibility of CSRm dipoles is less than P 2 x 10(-4), which can meet the requirements of CSR. In addition, the measurement errors are also analyzed.