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arXiv · 1804.10099

Luminosity Scans for Beam Diagnostics

Michael Hostettler·Kajetan Fuchsberger·Giulia Papotti·Tatiana Pieloni·Yannis Papaphilippou
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Abstract

A new type of fast luminosity separation scans ("Emittance Scans") was introduced at the CERN Large Hadron Collider (LHC) in 2015. The scans were performed systematically in every fill with full-intensity beams in physics production conditions at the Interaction Point (IP) of the Compact Muon Solenoid (CMS) experiment. They provide both emittance and closed orbit measurements at a bunch-by-bunch level. The precise measurement of beam-beam closed orbit differences allowed a direct, quantitative observation of long-range beam-beam PACMAN effects, which agrees well with numerical simulations from an improved version of the TRAIN code.

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Michael Hostettler, Kajetan Fuchsberger, Giulia Papotti, Tatiana Pieloni, Yannis Papaphilippou. 2018-04-26. Luminosity Scans for Beam Diagnostics. https://doi.org/10.1103/physrevaccelbeams.21.102801

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