Beam deceleration performance of the Fermilab Main Injector

The Fermilab Main Injector was designed to accelerate protons and antiprotons from a momentum of 8.889 GeV/c to 150 GeV/c. In order to study antiproton deceleration, for the ultimate purpose of storing them in a Penning trap, the Main Injector was used to decelerate protons from the injection momentum down to the goal of 2.0 GeV/c. In this paper the operational experience of working with the Main Injector as a decelerator is presented.