The Cornell-BNL FFAG-ERL Test Accelerator: White Paper

Ivan Bazarov; John Dobbins; Bruce Dunham; Georg Hoffstaetter; Christopher Mayes; Ritchie Patterson; David Sagan; Ilan Ben-Zvi; Scott Berg; Michael Blaskiewicz; S. J. Brooks; Kevin Brown; Wolfram Fischer; Yue Hao; Wuzheng Meng; François Méot; Michiko Minty; Stephen Peggs; Vadim Ptitsin; Thomas Roser; Peter Thieberger; Dejan Trbojevic; Nick Tsoupas

arXiv · 1504.00588

The Cornell-BNL FFAG-ERL Test Accelerator: White Paper

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Abstract

The Cornell-BNL FFAG-ERL Test Accelerator (C$\beta$) will comprise the first ever Energy Recovery Linac (ERL) based on a Fixed Field Alternating Gradient (FFAG) lattice. In particular, we plan to use a Non Scaling FFAG (NS-FFAG) lattice that is very compact and thus space- and cost- effective, enabling multiple passes of the electron beam in a single recirculation beam line, using the superconducting RF (SRF) linac multiple times. The FFAG-ERL moves the cost optimized linac and recirculation lattice to a dramatically better optimum. The prime accelerator science motivation for C$\beta$ is proving that the FFAG-ERL concept works. This is an important milestone for the Brookhaven National Laboratory (BNL) plans to build a major Nuclear Physics facility, eRHIC, based on producing 21 GeV electron beams to collide with the RHIC ion beams. A consequence of the C$\beta$ work would be the availability of significantly better, cost-effective, compact CW high-brightness electron beams for a plethora of scientific investigations and applications, such as X-ray sources, dark-matter and dark-energy searches, and industrial high-power Free-Electron Laser (FEL) applications. C$\beta$ brings together the resources and expertise of a large DOE National Laboratory, BNL, and a leading research university, Cornell. C$\beta$ will be built in an existing building at Cornell, for the most part using components that have been developed under previous R&D programs, including a fully commissioned world-leading photoemission electron injector, a large SRF accelerator module, and a high-power beam stop. The only elements that require design and construction from scratch is the FFAG magnet transport lattice. This white paper describes a project that promises to propel high-power, high-brightness electron beam science and applications to an exciting new level.

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Ivan Bazarov, John Dobbins, Bruce Dunham, Georg Hoffstaetter, Christopher Mayes, Ritchie Patterson, David Sagan, Ilan Ben-Zvi, Scott Berg, Michael Blaskiewicz, S. J. Brooks, Kevin Brown, Wolfram Fischer, Yue Hao, Wuzheng Meng, François Méot, Michiko Minty, Stephen Peggs, Vadim Ptitsin, Thomas Roser, Peter Thieberger, Dejan Trbojevic, Nick Tsoupas. 2015-04-02. The Cornell-BNL FFAG-ERL Test Accelerator: White Paper. https://arxiv.org/abs/1504.00588

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