Development of a Nb3Sn racetrack magnet for a 10T superconducting wiggler

We are designing a superconducting wiggler with an extremely high field. The wiggler will be used as a synchrotron-radiation source after inserting a storage ring. The wiggler will produce hard X-rays by a high field. We have chosen a field strength of 10T for our purpose. In order to obtain such a high field, we propose the use of Nb3Sn for the superconducting material. It is preferred to wind the material into a racetrack shape to be used as wiggler magnets, rather than using a cylindrical shape like that used in a solenoid. However, there is much difficulty to wind the material into a racetrack shape, and to minimize the stresses acting on the coil. We made a racetrack magnet for the R and D of Nb3Sn technology. Here, we present the results due to the characteristics of the Nb3Sn racetrack magnet. (author)