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arXiv · 2503.13209

High-resolution computed tomography of two-dimensional beam profile using dual-axis rotating wire

Rin Ota·Nanako Nakajima·Ryuto Takemasa·Hiroya Tamaru·Yoko Shiina·Yuji Nakano
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Abstract

The use of a wire probe is a robust method for beam profile measurement, but it can only provide a 1D projection of the beam profile. In this study, we developed a novel method for measuring a beam projected from a 360° angle by a dual-axis rotation of a wire probe and obtaining a complete 2D profile via image reconstruction. We conducted a proof-of-principle study using an Ar+ ion beam and optimized the reconstruction algorithm. The experimental results showed that the use of the order subsets expectation maximization (OS-EM) algorithm is the most reasonable method, providing a highly accurate absolute 2D beam profile within a processing time on the millisecond scale. Furthermore, analysis of 2D profiles at different probing positions provided the beam direction and the phase space distribution. This versatile method can be applied to various fields of quantum beam technologies, such as particle therapy, semiconductor processing, and material analysis, as well as basic scientific research.

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Rin Ota, Nanako Nakajima, Ryuto Takemasa, Hiroya Tamaru, Yoko Shiina, Yuji Nakano. 2025-09-13. High-resolution computed tomography of two-dimensional beam profile using dual-axis rotating wire. https://arxiv.org/abs/2503.13209

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