Quench performance of superconducting quadrupole magnets for the new Fermilab low beta insertion

Construction and testing of the components for the new Tevatron D0/B0 low beta insertion are nearly complete. The devices include superconducting cold iron quadrupoles utilizing a two-shell, cos2 theta coil geometry with a 7.6-cm aperture. The maximum design gradient is 1.41 T/cm at an operating current of 4832 A. They have the highest current density with the highest peak field on the winding of any quadrupole yet built. The authors summarize the quench performance and ramp rate sensitivity of the two-shell design and relate the performance characteristics to the relevant aspects of design and fabrication.<>