JACoW logo

Joint Accelerator Conferences Website

The Joint Accelerator Conferences Website (JACoW) is an international collaboration that publishes the proceedings of accelerator conferences held around the world.

RIS citation export for WEPTS049: Flat-Bottom Instabilities in the CERN SPS

AU  - Schwarz, M.
AU  - Iliakis, K.
AU  - Lasheen, A.
AU  - Papotti, G.
AU  - Repond, J.
AU  - Shaposhnikova, E.N.
AU  - Timko, H.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Flat-Bottom Instabilities in the CERN SPS
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - At beam intensities of 2.6·10¹¹ protons per bunch, required at SPS injection for the High Luminosity LHC beam, longitudinal instabilities can degrade the beam quality delivered by the SPS, the LHC injector at CERN. In this paper, we concentrate on beam instability at flat bottom. The dependence of the instability threshold on longitudinal emittance and LLRF system settings was measured, to help identify the impedance driving this instability. While reducing the longitudinal emittance reduces the losses at injection, it can drive the beam unstable. The LLRF system of the SPS (partially) compensates beam loading, but also affects the instability. The effect of the different LLRF systems (feedback, feedforward, phase loop and longitudinal damper) and fourth harmonic RF system on the instability was investigated. The measurements are compared with simulations performed with the longitudinal tracking code BLonD.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 3224
EP  - 3227
KW  - simulation
KW  - impedance
KW  - feedback
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-WEPTS049
UR  - http://jacow.org/ipac2019/papers/wepts049.pdf
ER  -