Design of main dipoles and quadrupoles for the SSC low energy booster

The Low Energy Booster (LEB) is a synchrotron which accelerates bunches of protons from a momentum of 1.2 GeV/c at injection to a momentum of 12.0 GeV/c at extraction. The main bending dipoles with a peak field of 1.3 Tesla and the main focussing and defocussing quadrupoles with a peak gradient of about 14.9 Tesla/m operate on the same power supply which ramps up sinusoidally from a current of 0.1 times the peak value at injection to the peak current in a 10 Hz cycle. The ratio of the gradient of the quadrupole to the field strength of the dipole should be constant during the current cycles in order to avoid a tune shift. Also, the magnets have to be designed to achieve the prescribed field quality and keep the multipoles within certain limits so as to keep the emittance growth during the acceleration to a minimum. This paper describes the design of the LEB dipoles and quadrupoles designed with this criteria