Performance of 1-m Long / 75-mm Bore Superconducting Prototype Coils for HERA

Two short prototypes of the new HERA superconducting dipole magnets with 75 mm inner bore have been built and tested in a bath cryostat. Both coils have reached the short sample current of the cable after a few training steps. The quench current depends linearly on the temperature between 4.0 and 5.0 K. The field quality of both coils is in general within specifications. There is no current dependence of the higher harmonics except for the well-known hysteresis due to persistent currents.