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arXiv · 2602.01504

First Experimental Demonstration of Beam Storage by Three-Dimensional Spiral Injection Scheme for Ultra-Compact Storage Rings

R. Matsushita·H. Iinuma·S. Ohsawa·H. Nakayama·K. Furukawa·S. Ogawa·N. Saito·T. Mibe·M. A. Rehman
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Abstract

Three-dimensional spiral injection enables beam storage in ultra-compact rings with nanosecond revolution periods. We report first storage of a $297 \, \mathrm{keV/}c$ electron beam in a $22 \,\mathrm{cm}$ weak-focusing ring with a $4.7\,\mathrm{ns}$ revolution period using a $140\,\mathrm{ns}$ kicker pulse. A scintillating-fiber detector observes signals $>5\sigma$ above noise for $\geq 1\, \mathrm{\mu s}$, and varying the weak-focusing field potential shifts the stored-beam region, consistent with Monte Carlo predictions, validating beam storage. This proof-of-principle opens a path to ultra-compact storage rings for next-generation precision measurements.

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R. Matsushita, H. Iinuma, S. Ohsawa, H. Nakayama, K. Furukawa, S. Ogawa, N. Saito, T. Mibe, M. A. Rehman. 2026-02-02. First Experimental Demonstration of Beam Storage by Three-Dimensional Spiral Injection Scheme for Ultra-Compact Storage Rings. https://arxiv.org/abs/2602.01504

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