The Spallation Neutron Source (SNS) and its beam diagnostic systems were designed and constructed by a partnership of several National Laboratories. During the successful commissioning in 2006, a temporary imaging system was deployed to complement the standard suite of beam diagnostics. Since then, the SNS has ramped up beam power and now operates as a megawatt class facility. In parallel, a permanent target imaging system was developed with challenging goals of measuring the beam properties at the target during full power operation, and making these measurements throughout the life of each target. Through a collaborative development effort, this system was designed and deployed in time for replacement of the first target. It consists of a thermal-sprayed luminescent coating deposited on the target's water shroud, a radiation-tolerant optical system installed on the proton beam window assembly, and an image acquisition system integrated with the accelerator control system. The luminescent coating survived for the entire life of the second target, and the optics survived for the entire life of the second proton beam window assembly. The success is tempered by some remaining challenges, primarily the determination of the system's absolute accuracy. This talk will include a brief history of SNS' collaborative development, details of the target imaging system design and performance, and results from related neutronic and audio studies.
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PDF version (2011-01-20 seminar at ESS shea final.pdf, 6.3 MB)