Segmented foil SEM grids for high-intensity proton beams at Fermilab

We present recent beam data from a new design of a profile monitor for proton beams at Fermilab. The monitors, consisting of grids of segmented Ti foils 5 /spl mu/m thick, are secondary-electron emission monitors (SEM's). We review data on the device's precision on beam centroid position, beam width, and on beam loss associated with the SEM material placed in the beam.