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DOE OSTI · 1909098

A realistic guide misalignment model for the Second Target Station instruments at the Spallation Neutron Source

Lin, Jiao Y. Y.·Huegle, Thomas·Coates, Leighton·Stoica, Alexandru Dan
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Abstract

The Second Target Station (STS) at the Spallation Neutron Source, including a suite of initial instrument concepts, are being designed in Oak Ridge. The moderator size at STS is significantly smaller than that of the First Target Station, making the guide misalignment a more prominent concern. Here a realistic misalignment model based on Monte Carlo neutron ray tracing simulation was developed to evaluate the impacts of both the random misalignment and floor settlement on the performance of a toy model of 150 m straight guide system, and MENUS, an STS instrument concept with a typical guide design of two opposing Montel mirrors. The study shows that longer instruments, and instruments with complex curved mirrors/guides are sensitive to significant performance penalties due to misalignments.

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Lin, Jiao Y. Y., Huegle, Thomas, Coates, Leighton, Stoica, Alexandru Dan. 2022-12-10. A realistic guide misalignment model for the Second Target Station instruments at the Spallation Neutron Source. https://doi.org/10.1016/j.nima.2022.167881

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