The BESIII detector magnet

Publisher Summary BESIII (Beijing Spectrometer III) is a detector designed to run in the autumn 2007 at a 1 ╳ 10 33 cm -2 s -1 luminosity @1.89 GeV at BEPCII (Beijing Electron–Positron Collider II) at IHEP Beijing. It has a 1 T superconducting solenoid magnet with the inner winding diameter of 2962 mm, winding length of 3532 mm, and a 600 tonne flux return yoke. The indirectly cooled, pure aluminum stabilized single layer coil is internally wounded with a 4 kA superconductor. The magnet design is described. The NbTi/Cu superconductor has been delivered and the critical current test of a short sample of the superconductor has been performed. An inner winding machine is under construction.