CERN Accelerating science

Preprint
Report number	CERN-ACC-2020-0001
Title	Deliverable 2.7: Analysis of the existing sources of blow-up in the SPS by experiments and estimation/measurement of the effect of the crab cavities in the SPS
Author(s)	Alekou, Androula (University of Manchester (GB)) ; Antoniou, Fanouria (CERN) ; Appleby, Robert Barrie (University of Manchester (GB)) ; Bartosik, Hannes (CERN) ; Calaga, Rama (CERN) ; Carla', Michele (CERN) ; Carver, Lee Robert (University of Liverpool (GB)) ; Papaphilippou, Yannis (CERN) ; Welsch, Carsten Peter (University of Liverpool (GB))
Publication	2020
Imprint	09 Jan 2020
Number of pages	18
Subject category	Accelerators and Storage Rings
Accelerator/Facility, Experiment	CERN SPS CERN LHC
Project	CERN HL-LHC
Technology	Radiofrequency
Processes	Beam Dynamics
Keywords	Crab Cavities ; HL-LHC ; SPS
Abstract	The Crab Cavities (CCs) may induce emittance growth, driven by phase and amplitude jitter, and lead to a degradation of the High Luminosity LHC (HL-LHC) beam. Furthermore, the tight HL-LHC space constraints call for non-axially symmetric cavity designs that come with higher order non-linearities which can affect the long-term dynamic aperture (DA). In order to study the effect the CCs have on the beam and the engineering challenges to validate the pre-series design, a prototype HL-LHC CC set was installed in the SPS machine in the year-end technical stop (YETS) of 2017-2018, and the first ever CC tests with protons were performed in 2018. This note is a collection of the reports and work done on the emittance growth measurements prior and after the CC installation, as well as simulations and measurements performed to study the CC and SPS non linearities effect. Finally, a summary of the instrumentation observations of the SPS CC experimental measurements is presented.
Submitted by	[email protected]