Pulse-mode measurement of electron beam halo using diamond-based detector

RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan(Received 16 September 2011; published 6 February 2012)Using a diamond-based detector, the electron beam halo in a high-energy accelerator can be measuredwith a lower detection limit than that using other instruments, such as a core monitor, a dose meter, or anoptical fiber. We have successfully measured an electron beam halo using diamond-based detectorsoperating in the ionization mode, which were installed in the beam duct to measure the intensity of thebeam halo directly. Pulse-by-pulse measurements were adopted to suppress the background noiseefficiently. Feasibility tests on the diamond-based detector and beam halo monitor were performed inthe beam dump area of the 8 GeV SPring-8 synchrotron booster and at the 250 MeV SPring-8 CompactSASE Source test accelerator for the SPring-8 Angstrom Compact free electron LAser (SACLA),respectively.Weachievedalowerdetectionlimitof2 10