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Update on scraper scans. Lene Drosdal. New scan strategy. Large tail population observed Always scan up to 100% of beam Beam core: Fit single Gaussian of points >50% Beam with tails: Fit double Gaussian. Correct position. Tail identification . Drift of beam position.
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Update on scraper scans LeneDrosdal
New scan strategy • Large tail population observed Always scan up to 100% of beam • Beam core: Fit single Gaussian of points >50% • Beam with tails: Fit double Gaussian Correct position Tail identification
Drift of beam position • 3 scans confirm that the centre of the beam is moving: • Beam size is within error bars/intensity variations on both fits • Beam size from 1Gauss core slightly larger than core of 2Gauss core Horizontal plane: ~1mm Vertical plane: >4mm
Tail investigations • Scans done at different times in the SPS cycle – vertical plane: • Small tails at flat-bottom – well corrected from injectors • Tails grow during ramp and possibly flat-bottom
Outlook • More scans to be done: Scrape full beam, multiple scans to see how the tails are behaving • - difficult to get time for scans • Scraper settings now stored in IQC easy to monitor changes in settings (Indirectly beam position movement)