  A 4600 Hz fast ramping synchrotron is studied as an economical way of
accelerating muons from 4 to 20 GeV/c for a neutrino factory. Eddy current
losses are minimized by the low machine duty cycle plus thin grain oriented
silicon steel laminations and thin copper wires. Combined function magnets with
high gradients alternating within single magnets form the lattice. Muon
survival is 83%.
