Ribbon Electron Beam Profile Monitor for Bunched Beam Tomography

Advanced beam diagnostics are essential for high performance accelerator beam production and for reliable accelerator operation. It is important to have noninvasive diagnostics which can be used continuously with intense beams of accelerated particles. Recently, an electron probe was tested to determine accelerated particle density distributions. However, the prototype apparatus used for this diagnostic is large and complex which restricts its wider use for tomography of accelerated bunches. In a novel proposed device for realization of electron probe tomography a strip cathode is used for ribbon electron beam formation instead of a scanning of pencil beam used in the previous electron probe bunch profile monitors. The apparatus with the strip cathode is smaller, has simpler design and less expensive manufacturing, has better magnetic shielding, has higher sensitivity, higher resolution, has better measurement accuracy and better time resolution. With this device it is possible to develop almost ideal tomography diagnostics of bunches in linear accelerators and in circular accelerators and storage rings. For small bunch diagnostic will be used fan like flux of electrons generated with the strip cathode and transaxial electrostatic lenses. A prototype electron probe source with a strip cathode will be developed and tested in Phase I. Some versions of thermionic cathodes and field emission cathodes with nanotubes will be developed and tested. In Phase II the full tomography system with improved hardware and software will be developed and tested in the SNS storage ring. Commercial applications and other benefits: The proposed electron probe tomography system with the strip cathode should be the most advanced system for detailed diagnostics of accelerated beams. It will be used in all advanced accelerators and storage rings such as SNS, Tevatron, RHIC, LHC, ISIS, KEK and many others. Large scale production of these diagnostics will have significant impact to improve the operation of these and other new multi-billion dollar facilities at low cost. Another aspect will be the commercial consequences to Muons, Inc. to generate a product and service for a significant market that is appropriate for a small company. Ribbon beam can be used also for efficient microwave generation.