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arXiv · 2608.23387

White Paper on a Novel FFA-Based CEBAF Upgrade to 22 GeV

S. A. Bogacz·R. M. Bodenstein·K. E. Deitrick·B. R. Gamage·R. Kazimi·D. Khan·E. Nissen·S. Ogur·Y. Roblin·P. Rossi·J. S. Berg·S. J. Brooks·D. Trbojevic·V. Morozov
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Abstract

We present a conceptual design for a cost-effective upgrade of the Continuous Electron Beam Accelerator Facility (CEBAF) to 22 GeV using non-scaling fixed-field alternating-gradient (FFA) arcs built from Halbach-style permanent magnets. Building on the eight-pass energy-recovery demonstration at the Cornell--BNL CBETA test accelerator, the design replaces the highest-energy recirculation arcs with a pair of FFA arcs that simultaneously transport six passes spanning a factor-of-two momentum range. We describe the machine layout; including the injector, recirculating linacs, spreaders and recombiners, FFA arcs, splitters, transition and extraction regions; together with beam-dynamics validation studies covering emittance growth, synchrotron-radiation-driven depolarization, and orbit correction, and we summarize permanent-magnet design, prototyping, and radiation-resiliency results. This white paper documents the accelerator physics underpinning a staged path to 22 GeV that preserves CEBAF's multi-hall, high-luminosity, polarized-beam capabilities.

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S. A. Bogacz, R. M. Bodenstein, K. E. Deitrick, B. R. Gamage, R. Kazimi, D. Khan, E. Nissen, S. Ogur, Y. Roblin, P. Rossi, J. S. Berg, S. J. Brooks, D. Trbojevic, V. Morozov. 2026-08-24. White Paper on a Novel FFA-Based CEBAF Upgrade to 22 GeV. https://arxiv.org/abs/2608.23387

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