Chromaticity compensation of a ghost collider

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Persistent URL	http://purl.org/net/epubs/work/66113021
Record Status	Checked
Record Id	66113021
Title	Chromaticity compensation of a ghost collider
Contributors	Dr B Gamage (Jefferson Lab, VA, USA) (Pr.Au.), Dr A Hutton (Jefferson Lab, VA, USA), Prof P H Williams (STFC Daresbury Lab., & Cockcroft Inst.)
Abstract	The ghost collider final focus system is a pure quadrupole-drift beamline targeting \beta* = 2 mm at four serial interaction points, with peak \beta-functions reaching ∼65 km in the final triplet. Beam tracking simulations reveal that a nominal bunch develops a pronounced C-shape in longitudinal phase space at IP1, with bunch length growing from 0.15 mm to ∼2.3 mm — a factor of ∼15× increase that directly reduces luminosity. The mechanism is identified as chromatically amplified betatron path length: off-momentum particles acquire enlarged betatron amplitudes in the high-\beta final triplet, generating excess path length via the geometric \Delta z integral. When combined with the geometric hourglass effect, this distortion poses a challenge to maximizing luminosity within the current lattice design.
Organisation	ASTeC , ASTeC-AP , CI , STFC
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Language	English (EN)

Type	Details	URI(s)	Local file(s)	Year
Paper In Conference Proceedings	In 17th International Particle Accelerator Conference (IPAC 26), Deauville, France, 17-22 May 2026, (2026).		WEP1313.pdf	2026