Aperture Measurements with AC Dipole at the Large Hadron Collider

Nuria Fuster-Martinez, Roderik Bruce, J Dilly, Ewan Maclean, Tobias Persson, Stefano Redaelli, Rogelio Tomás, Laurence Nevay

Research output: Chapter in Book/Report/Conference proceedingConference contribution


Global aperture measurements are crucial for a safe oper- ation and to push the performance of the LHC. In particular, the knowledge of the global aperture at top energy allows pushing the optics to reduce the colliding beam sizes. The standard method used in the LHC commissioning requires using several low-intensity bunches for one measurement and makes bunches un-usable for other activities. This paper presents first global aperture measurements performed at injection with a new method using the AC dipole. This method consists in exciting large coherent oscillations of the beam without spoiling its emittance. A gentle control of the oscillation amplitude enables re-using the beams for several measurements. These measurements are compared with aperture measurements performed using the standard method based on destructive blow-up of bunches. Possible benefits, for example for optics measurements, at top energy with squeezed optics, are elaborated.
Original languageEnglish
Title of host publication9th International Particle Accelerator Conference
PublisherJACoW Publishing
Number of pages4
ISBN (Electronic)978-3-95450-184-7
Publication statusPublished - Jun 2018
Event9th International Particle Accelerator Conference - JW Marriot Parq, Vancouver, Canada
Duration: 29 Apr 20184 May 2018


Conference9th International Particle Accelerator Conference
Abbreviated titleIPAC18
Internet address

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