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arXiv · 1907.13515

A Numerical Approach to Designing a Versatile Pepper-pot Mask for Emittance Measurement

Oznur Apsimon·Barney Williamson·Guoxing Xia
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Abstract

The pepper-pot method is a popular emittance measurement technique for high intensity beams at low energy such as those generated by photo-injectors. In this paper, the beam dynamics in the space charge dominated regime and analytical design criteria for a mask-based emittance measurement (pepper-pot method) are revisited. A tracking code developed to test the performance of a pepper-pot setup is introduced. Examples of such testing are presented with particle distributions that were generated using PARMELA under different focusing conditions. These distributions were numerically tested against a series of mask geometries suggested by analytical criteria. The resulting fine-tuned geometries and beam dynamics features observed are presented.

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Oznur Apsimon, Barney Williamson, Guoxing Xia. 2019-08-01. A Numerical Approach to Designing a Versatile Pepper-pot Mask for Emittance Measurement. https://doi.org/10.1016/j.nima.2019.162485

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