Longitudinal emittance measurements in the Fermilab Recycler Ring

The Recycler Ring (RR) is a new 8GeV antiproton storage ring at Fermilab. Presently, this machine is being commissioned using protons from the Booster. It uses barrier buckets for stacking, un-stacking and storing the beam. At any given time, the RR is capable of storing proton or antiproton beams in multiple segments azimuthally. These segments of the beam may have widely differing longitudinal emittance and beam intensities and bunch lengths. It is highly essential to be able to measure the longitudinal emittance and keep track of the longitudinal dynamics at various stages of the operation of the RR. In this paper, we discuss a few methods of longitudinal emittance measurements in barrier buckets and discuss their merits and demerits.