Ramp

This means to excite a magnet with a time dependent excitation current. A time varying excitation current for a magnet is used either to track changing beam energy or to reduce average power dissipation by reducing the excitation when the magnetic field is not required. At Fermilab, the Main Injector and Tevatron bending magnetic field varies with the energy of the accelerating protons in order to confine them within the beam pipe.