Contribution to a conference proceedings/Journal Article

PUBDB-2026-02803

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Bayesian Optimisation of FCC-ee Booster beam parameters with Damping Wigglers

Thakur, S. (Corresponding author)DESY* ; Paraschou, K.DESY* ; Agapov, I.DESY*

2026
Springer Nature Hamburg

Abstract: The large circumference of the FCC-ee booster makes natural radia-tion damping very slow, while the demanding Z-mode scenario simultaneouslyrequires the maximum beam charge within a minimal cycle time. Consequently,the last injected bunch does not reach the required transverse emittance at ex-traction. Damping wigglers provide additional damping, but also increase theenergy spread through quantum excitation. To address this, damping wigglersare explored both at the injection and dynamically during the energy ramp. Thebeam evolution is studied with an analytical model, benchmarked against par-ticle tracking with the XSuite software. Multi-objective Bayesian optimizationis then employed to identify wiggler configurations that minimise transverseemittance while controlling the increase of the energy spread. It is found thatthe horizontal emittance can be reduced by up to a factor of four, so the emit-tance requirement is easily met and the energy spread becomes the limitingfactor. The energy-spread requirement at extraction is nevertheless also met fora sufficiently large number of wigglers

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Contributing Institute(s):

1. Beschleunigerphysik (MPY)

Research Program(s):

1. 621 - Accelerator Research and Development (POF4-621) (POF4-621)

Experiment(s):

1. Future Circular Collider

Appears in the scientific report 2026

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Database coverage:
; ; ; Article Processing Charges ; Clarivate Analytics Master Journal List ; DOAJ Seal ; Emerging Sources Citation Index ; Fees ; IF < 5 ; JCR ; SCOPUS ; Web of Science Core Collection

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