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arXiv · 2110.02816

Crystal slow extraction of positrons from DAFNE: the SHERPA project

M. Garattini·D. Annucci·O. R. Blanco-Garcia·P. Gianotti·S. Guiducci·A. Liedl·M. Raggi·P. Valente
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Abstract

The SHERPA project aim is to develop an efficient technique to extract a positron beam from one of the accelerator rings composing the DAFNE complex at the Frascati National Laboratory of INFN, setting up a new beam line able to deliver positron spills of O(ms) length, excellent beam energy spread and emittance. The most common approach to slowly extract from a ring is to increase betatron oscillations approaching a tune resonance in order to gradually eject particles from the circulating beam. SHERPA proposes a paradigm change using coherent processes in bent crystals to kick out positrons from the ring, a cheaper and less complex alternative. A description of this innovative non-resonant extraction technique is reported in this manuscript, including its performance preliminary estimation.

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M. Garattini, D. Annucci, O. R. Blanco-Garcia, P. Gianotti, S. Guiducci, A. Liedl, M. Raggi, P. Valente. 2021-10-06. Crystal slow extraction of positrons from DAFNE: the SHERPA project. https://arxiv.org/abs/2110.02816

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