002886518 001__ 2886518
002886518 003__ SzGeCERN
002886518 005__ 20240116234641.0
002886518 0247_ $$2DOI$$9JACOW$$a10.18429/JACoW-IPAC2023-TUPA157
002886518 0248_ $$aoai:cds.cern.ch:2886518$$pcerncds:FULLTEXT$$pcerncds:CERN:FULLTEXT$$pcerncds:CERN
002886518 035__ $$9https://inspirehep.net/api/oai2d$$aoai:inspirehep.net:2716620$$d2024-01-15T13:32:36Z$$h2024-01-16T05:17:04Z$$mmarcxml
002886518 035__ $$9Inspire$$a2716620
002886518 041__ $$aeng
002886518 100__ $$aPapotti, Giulia$$uCERN
002886518 245__ $$9JACOW$$aSPS fixed target spill quality improvements in the longitudinal plane
002886518 260__ $$c2023
002886518 260__ $$c2023
002886518 300__ $$a4 p
002886518 520__ $$9JACOW$$aThe SPS proton fixed target beams are spilled via a third integer resonant extraction, for which high momentum spread is beneficial. To increase the momentum spread prior to the slow extraction, the bunches are stretched at the unstable phase by inverting the sign of the RF voltage. The RF phase is then flipped back, and the voltage is turned off when the bunch distribution is rotated to the maximum momentum spread. The past production scheme additionally relied on uncontrolled longitudinal blow-up of the unstable beam during the acceleration ramp. After the major upgrade of the main RF system and a successful impedance reduction campaign, the spill quality was significantly compromised. This contribution summarizes the efforts to recover, and improve, the spill quality. The use of the fourth harmonic RF system and controlled longitudinal emittance blow-up are used for beam stabilization along the ramp. Moreover, RF counter phasing is applied during the first part of the de-bunching to profit from the cavity impedance reduction of the feedback systems.
002886518 540__ $$aCC-BY-4.0$$bJACOW$$uhttps://creativecommons.org/licenses/by/4.0
002886518 65017 $$2SzGeCERN$$aAccelerators and Storage Rings
002886518 6531_ $$9author$$aimpedance
002886518 6531_ $$9author$$aextraction
002886518 6531_ $$9author$$abunching
002886518 6531_ $$9author$$aexperiment
002886518 6531_ $$9author$$atarget
002886518 6531_ $$9author$$aproton
002886518 6531_ $$9author$$aacceleration
002886518 6531_ $$9author$$acontrols
002886518 690C_ $$aARTICLE
002886518 690C_ $$aCERN
002886518 700__ $$aSpierer, Arthur$$uCERN
002886518 700__ $$aQuartullo, Danilo$$uCERN
002886518 700__ $$aHagmann, Gregoire$$uCERN
002886518 700__ $$aKarpov, Ivan$$uCERN
002886518 700__ $$aPiandani, Roberto$$uSan Luis Potosi U.
002886518 773__ $$cTUPA157$$pJACoW IPAC$$qIPAC2023$$v2023$$wC23-05-07$$y2023
002886518 8564_ $$82504935$$s429806$$uhttps://cds.cern.ch/record/2886518/files/document.pdf$$yFulltext
002886518 960__ $$a13
002886518 962__ $$b2858945$$kTUPA157$$nvenice20230507
002886518 980__ $$aARTICLE
002886518 980__ $$aConferencePaper