Techniques for intense-proton-beam profile measurements

In a collaborative effort with industry and several national laboratories, the Accelerator Production of Tritium (APT) facility and the Spallation Neutron Source (SNS) linac are presently being designed and developed at Los Alamos National Laboratory (LANL). The APT facility is planned to accelerate a 100 mA H + cw beam to 1.7 GeV and the SNS linac is planned to accelerate a 1 to 4 mA-average, H-, pulsed-beam to 1 GeV. With typical rms beam widths of 1 to 3 mm throughout much of these accelerators, the maximum average-power densities of these beams are expected to be approximately 30 and 1 MW-per-square millimeter, respectively. Such power densities are too large to use standard interceptive techniques typically used for acquisition of beam profile information. This paper will summarize the specific requirements for the beam profile measurements to be used in the APT, SNS, and the Low- Energy Development Accelerator (LEDA) — a facility to verify the operation of the first 20 MeV section of APT. This paper will also discuss the variety of profile measurement choices discussed at a recent high-average-current beam profile workshop held in Santa Fe, NM, and will present the present state of the design for the beam profile measurements planned for APT, SNS, and LEDA.