A5065289857- Particle Accelerators and Free-Electron Lasers
- Particle accelerators and beam dynamics
- Superconducting Materials and Applications
- Gyrotron and Vacuum Electronics Research
- Particle Detector Development and Performance
- Particle physics theoretical and experimental studies
- Medical Imaging Techniques and Applications
- Laser-Plasma Interactions and Diagnostics
- Laser-Matter Interactions and Applications
- Photonic and Optical Devices
- X-ray Spectroscopy and Fluorescence Analysis
- Radiation Detection and Scintillator Technologies
- Silicon and Solar Cell Technologies
- Nuclear Physics and Applications
- Surface and Thin Film Phenomena
- Electromagnetic Simulation and Numerical Methods
- Atomic and Molecular Physics
- Silicon Carbide Semiconductor Technologies
European Organization for Nuclear Research
2015-2024
Université Paris-Sud
2017-2018
AWAKE is a proton-driven plasma wakefield acceleration experiment. % We show that the experimental setup briefly described here ready for systematic study of seeded self-modulation 400\,GeV proton bunch in 10\,m-long rubidium with density adjustable from 1 to 10$\times10^{14}$\,cm$^{-3}$. short laser pulse used ionization vapor propagates all way along column, suggesting full vapor. occurs bunch, at time and follows affects bunch.
Beam instabilities cover a wide range of effects in particle accelerators and they have been the subjects intense research for several decades. As machines performance was pushed new mechanisms were revealed nowadays challenge consists studying interplays between all these intricate phenomena, as it is very often not possible to treat different separately. The aim this paper review main mechanisms, discussing particular recent developments beam instability theories simulations.
The beam longitudinal dynamics code blond, utilized tool, has been developed at CERN since 2014. It emerged as a central tool for conducting simulations. In this paper, we present modular simulation suite and the various physics models that can be included combined by user. We detail reference frame, equations of motion, plethora options radio-frequency parameters such phase noise, fixed-field acceleration, feedback accelerators, well modeling collective effects synchrotron radiation. also...
Abstract In the framework of High Luminosity Upgrade LHC (HL-LHC) beam intensity from injectors must be doubled while keeping longitudinal parameters unchanged. As such, high-quality beams with high intensities are required also Proton Synchrotron (PS). The coupling impedance plays a crucial role and mitigation measures taken to remain within stringent budget. Kicker magnets important contributors overall broadband PS. Moreover, detailed study kicker impedances revealed additional resonant...
The relatively recent Beam Longitudinal Dynamics code BLonD has already been applied to a wide range of studies for all present CERN synchrotrons. Its application area ranges from RF manipulations, over single and multi-bunch interactions with impedance, the action feedback loops noise. In this paper, we benchmarks comparisons measurements, theory, or other codes, which have increased greatly trust in code. Tests related bunch-to-bucket transfer, loops, diffusion due noise injection, as well...
The beam longitudinal dynamics code BLonD has been developed at CERN since 2014 and become a central tool for simulations. In this paper, we present modular simulation suite the various physics models that can be included combined by user. We detail reference frame, equations of motion, BLonD-specific options radio-frequency parameters such as phase noise, fixed-field acceleration, feedback accelerators, well modeling collective effects synchrotron radiation. also methods generating...
Microwave instability in the Super Proton Synchrotron (SPS) at CERN is one of main limitations to reach requirements for High Luminosity-LHC project (increased beam intensity by a factor 2). To identify impedance source responsible instability, measurements were carried out probe SPS impedance. The method presented this paper relies on unstable spectra single bunches, injected with rf voltage switched off. modulation bunch profile gives information about sources driving microwave and...
The spectrum of long bunches injected into the ring with RF switched o has been used in SPS past to probe longitudinal coupling impedance. After a large campaign shielding 800 inter-magnet vacuum ports 1999 - 2001, microwave instability threshold was significantly increased and high-frequency beam became practically flat, apart from prominent peak at around 1.4 GHz. As corresponding impedance could potentially lead high intensity observed now energies SPS, search source this launched. Using...
Abstract In view of the High Luminosity (HL) upgrade LHC, beam intensity must be doubled in injector chain. To perform reliable dynamics simulations, coupling impedance injectors, such as Proton Synchrotron (PS), followed closely by including all contributing elements into model. The existing kicker magnets PS had been optimized for large kick strength and short rise/fall times, but not necessarily to minimise impedance. Hence, unwanted induced voltage can build up their electrical circuits,...
The LHC Injectors Upgrade (LIU) project at CERN aims doubling the total intensity of lead ion beam for High-Luminosity (HL) LHC. Achieving this goal requires using momentum slip-stacking in SPS, injector. Slip-stacking will be applied on an intermediate energy plateau to interleave two batches, reducing bunch spacing from 100 ns 50 and thus increasing number bunches injected into Realistic macro-particle simulations, with present SPS impedance model are used study design complicated...
A reliable impedance model of a particle accelerator can be built by combining the beam coupling impedances all components. This is necessary step to able evaluate machine performance limitations, identify main contributors in case an reduction required, and study interaction with other mechanisms such as optics nonlinearities, transverse damper, noise, space charge, electron cloud, beam-beam (in collider). The phases create realistic model, verify it experimentally, will reviewed,...
Longitudinal instabilities are one of the main limitations in CERN Super Proton Synchrotron (SPS) to reach beam parameters required for High Luminosity LHC project. In preparation SPS upgrade, possible remedies studied by performing macroparticle simulations using machine impedance model obtained from electromagnetic and measurements. To benchmark model, results compared with various this study, reactive part was probed measuring quadrupole frequency shift intensity, bunch length...
Longitudinal instabilities in the CERN PS are an important limitation to obtain expected beam intensity and longitudinal emittance at extraction framework of LHC Injector Upgrade (LIU) project. The observed coupled-bunch lead dipolar quadrupolar oscillations, as well uncontrolled blow-up for proton beams. A microwave instability with ion beams develops quickly transition crossing. To identify potential impedance sources these instabilities, two strategies were adopted. Firstly, measurements...
The first SPS impedance reduction programme has been completed in 2001, preparing the ring for its role as an injector of LHC. This action eliminated microwave instability on flat bottom and later nominal beam could be delivered to High Luminosity (HL-) LHC project is based with twice higher intensity than one. One important limitations are longitudinal instabilities minimum threshold reached 450 GeV top. In this paper work which was carried identify sources driving these described together...