Evaluation of High Stability Secondary Emission Monitors

A stable, remotely operated low scattering (θ = 0.246 mrad) secondary emission monitor (SEM) which was developed at Argonne National Laboratory (ANL) is described. Experimental results for secondary yield vs. energy of incident protons of 3.6 GeV/c to 12.33 GeV/c indicate that the yield increase is about 0.03%/GeV/c/A1 surface. Theoretical yield increase in the same energy range is about 0.02%/GeV/c/A1 surface. The overall yield/proton/A1 surface as observed at ANL increases from 2.7%/A1 surface at 3.6 GeV/c to 2.96%/A1 surface at 12.33 GeV/c.