Results and analysis of measurements on a proton‐source beam for halo formation studies

An important experiment investigating halo formation is in progress at Laboratoire National Saturne (LNS). Its purpose is to detect and measure the halo developed by an intense proton beam in a long magnetic quadrupole FODO channel (58 quadrupoles). Two different arrangements of apparatus built to measure the emittance and the brightness of the beam entering the FODO channel are described. The first one, the LNS method, is made up of a sampling hole and a multiwire profile monitor whereas the second one, the Service Physique et Techniques Nucleaires method, is made up of a scintillating screen and a high performance charge‐coupled device camera. Results and analysis of the measurements are presented.