A test of a superconducting solenoid for the mucool RF experiment

This report describes the results of a series of tests of a 440-mm warm bore split solenoid used for testing 805 MHz RF cavities. The solenoid consists of two coils each 250 mm long separated by a gap of 140 mm. The solenoid was designed to operate in two modes; a solenoid mode with the two coils hooked in the same polarity and a gradient mode with the two coils hooked in opposite polarity. In the solenoid mode, the magnet is designed to produce an induction of 5 T over a region that is about 400 mm long. In the gradient mode, the solenoid produces a field gradient of 25 T per meter along the axis over a distance of about 300 mm. The solenoid was designed to carry a force of over 3 MN that pushes the two coils apart, when the magnet is operated in the gradient mode. In order to carry this force, the coils are encased within aluminum shells, both inside and outside. Since this solenoid is encased in aluminum and the coils are potted, training was observed. The magnet training history and magnet field measurements are presented in this report