S. Doebert
A5058464362- Particle Accelerators and Free-Electron Lasers
- Particle accelerators and beam dynamics
- Laser-Plasma Interactions and Diagnostics
- Particle Detector Development and Performance
- Gyrotron and Vacuum Electronics Research
- Magnetic confinement fusion research
- Superconducting Materials and Applications
- Radiation Detection and Scintillator Technologies
- Pulsed Power Technology Applications
- Muon and positron interactions and applications
- Particle physics theoretical and experimental studies
- Atomic and Molecular Physics
- Plasma Diagnostics and Applications
- Radiation Therapy and Dosimetry
- Dark Matter and Cosmic Phenomena
- Ionosphere and magnetosphere dynamics
- Photocathodes and Microchannel Plates
- Electromagnetic Simulation and Numerical Methods
- Neutrino Physics Research
- Nuclear Physics and Applications
- International Science and Diplomacy
- Laser-Matter Interactions and Applications
- Solar and Space Plasma Dynamics
- Laser-induced spectroscopy and plasma
- Advanced X-ray Imaging Techniques
European Organization for Nuclear Research
2015-2024
Campbell Collaboration
2020-2022
Ulsan National Institute of Science and Technology
2021
Google (United States)
2019
University College London
2016
SLAC National Accelerator Laboratory
2004
Menlo School
2004
Linac Coherent Light Source
2004
High energy particle accelerators have been crucial in providing a deeper understanding of fundamental particles and the forces that govern their interactions. In order to increase or reduce size accelerator, new acceleration schemes need be developed. Plasma wakefield acceleration, which electrons plasma are excited, leading strong electric fields, is one such promising novel technique. Pioneering experiments shown an intense laser pulse electron bunch traversing plasma, drives fields 10s...
The Advanced Proton Driven Plasma Wakefield Acceleration Experiment (AWAKE) aims at studying plasma wakefield generation and electron acceleration driven by proton bunches. It is a proof-of-principle R&D experiment CERN the world׳s first experiment. AWAKE will be installed in former CNGS facility uses 400 GeV/c beam bunches from SPS. experiments focus on self-modulation instability of long (rms ~12 cm) bunch plasma. These are planned for end 2016. Later, 2017/2018, low energy (~15 MeV)...
We give direct experimental evidence for the observation of full transverse self-modulation a long, relativistic proton bunch propagating through dense plasma. The exits plasma with periodic density modulation resulting from radial wakefield effects. show that is seeded by ionization front created using an intense laser pulse copropagating bunch. extends over length following seed point. By varying one order magnitude, we frequency scales expected dependence on density, i.e., it equal to...
The seeded self-modulation of a relativistic, charged particle bunch in plasma is shown to grow both along the and plasma, resulting transverse wakefield amplitudes that far exceed initial seed values.
We show in experiments that a long, underdense, relativistic proton bunch propagating plasma undergoes the oblique instability, which we observe as filamentation. determine threshold value for ratio between transverse size and skin depth instability to occur. At threshold, outcome of experiment alternates filamentation self-modulation (evidenced by longitudinal modulation into microbunches). Time-resolved images density distribution reveal grows an observable level late along bunch,...
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.
Plasma wakefield acceleration is a promising technology to reduce the size of particle accelerators. The use high energy protons drive wakefields in plasma has been demonstrated during Run 1 AWAKE programme at CERN. Protons 400 GeV drove that accelerated electrons 2 under 10 m plasma. collaboration now embarking on with main aims demonstrate stable accelerating gradients 0.5–1 GV/m, preserve emittance electron bunches and develop sources scalable 100s metres beyond. By end 2, scheme should...
Experimental results show that hosing of a long particle bunch in plasma can be induced by wakefields driven short, misaligned preceding bunch. Hosing develops the plane misalignment, self-modulation perpendicular plane, at frequencies close to electron frequency, and are reproducible. Development depends on misalignment direction, its growth extent proton charge. Results have main characteristics theoretical model, relevant other plasma-based accelerators represent first characterization...
The baseline configuration of the Compact Linear Collider positron source is optimized at three different collision energy stages for both drive beam-based and klystron-based acceleration modes. hybrid target replaced with a single amorphous tungsten thickness electron beam spot size optimized. As result optimization, compared old configuration, yield has been improved by factor 1.65, enabling same reduction in bunch charge power primary beam. total deposited reduced 2.1. most realistic...
The CLIC study has developed compact, high-gradient, and energy-efficient acceleration units as building blocks for a future high-energy, electron-positron linear collider. components to construct such units, including RF sources, are now generally available in industry their properties promise cost-effective solutions making compact electron-based linacs (already crucial technology many research, medical, industrial facilities) more efficient compact. actively promoted supported spin-off...
The conversion of the CALIFES beamline CTF3 into “CERN Linear Electron Accelerator for Research” (CLEAR) facility was approved in December 2016. primary focus CLEAR is general accelerator R&D and component studies existing possible future applications. This includes high gradient acceleration methods, e.g. CLIC plasma technology, prototyping validation components, HL-LHC upgrade. also provides irradiation test capabilities characterisation electronic components medical A description with...
A long, narrow, relativistic charged particle bunch propagating in plasma is subject to the self-modulation (SM) instability. We show that SM of a proton can be seeded by wakefields driven preceding electron bunch. timing reproducibility and control are at level small fraction modulation period. With this seeding method, we independently amplitude seed with charge growth rate Seeding leads larger than instability case.
We use a relativistic ionization front to provide various initial transverse wakefield amplitudes for the self-modulation of long proton bunch in plasma. show experimentally that, with sufficient amplitude [$\ensuremath{\ge}(4.1\ifmmode\pm\else\textpm\fi{}0.4)\text{ }\text{ }\mathrm{MV}/\mathrm{m}$], phase modulation along is reproducible from event event, 3%--7% (of $2\ensuremath{\pi}$) rms variations all bunch. The not lower amplitudes. observe transition between these two regimes. Phase...
Electron acceleration by laser-plasma techniques is approaching maturity and getting ready for the construction of particle accelerators with dedicated applications. We present a general methodology showing how beam physics studies can be used to achieve specific parameter set in accelerator. Laser systems, plasma targets, magnetic component properties are designed optimize electron so as required performances. Beam its full 6D phase space studied from injection delivery end user, through...
The AWAKE collaboration prepares a proton driven plasma wakefield acceleration experiment using the SPS beam at CERN. A long bunch extracted from interacts with high power laser and 10 m rubidium vapor cell to create strong wakefields allowing sustained electron acceleration. probe these is created by an accelerator consisting of rf-gun booster structure. This source should provide beams intensities between 0.1 1 nC, lengths 0.3 3 ps emittance order 2 mm mrad. structure accelerate electrons...
The CLIC study has developed compact, high gradient and energy efficient acceleration units as building blocks for a linear collider high-energy physics. Many of these components are now available in industry. These properties promise cost effective solutions small accelerators variety applications. actively promoted supported such spin-off developments from the beginning. applications include beam manipulation diagnostic research linacs FEL light sources, compact Compton-scattering x-ray...
Abstract The Compact Linear Collider requires micron-level alignment of the key accelerator components within two 21 km main LINACs to achieve desired luminosity. Several Super Accelerating Structures (SAS) will be pre-aligned on a single common support structure 14μm. This then actively aligned relative Machine Reference Network, and in operation beam-based used final 1 μm required. A design for SAS pre-alignment system has been created, prototyped, tested, shown match performance 2.3...
Abstract Following the successful Run 1 experiment, Advanced Proton Driven Plasma Wakefield Acceleration Experiment (AWAKE) Run2 experiment requires design and implementation of a compact electron source. The “high-quality Electron Accelerator driven by Reliable Laser wakefield for Industrial uses” (EARLI) project aims to stand-alone high-quality injector based on laser accelerator (LWFA) as an alternative proposal AWAKE’s baseline X-band gun. This is currently in phase, including...
The AWAKE Collaboration has been formed in order to demonstrate proton-driven plasma wakefield acceleration for the first time. This technique could lead future colliders of high energy but a much reduced length when compared proposed linear accelerators. CERN SPS proton beam CNGS facility will be injected into 10 m cell where long bunches modulated significantly shorter micro-bunches. These micro-bunches then initiate strong with peak fields above 1 GV/m that harnessed accelerate bunch...
We study experimentally the longitudinal and transverse wakefields driven by a highly relativistic proton bunch during self-modulation in plasma. show that wakefields' growth amplitude increase with increasing seed as well charge using maximum radius of distribution measured on screen downstream from externally injecting electrons measuring their final energy. Measurements agree trends predicted theory numerical simulations validate our understanding development self-modulation. Experiments...
Abstract In 2017, AWAKE demonstrated the seeded self-modulation (SSM) of a 400 GeV proton beam from Super Proton Synchrotron at CERN. The angular distribution protons deflected due to SSM is quantitative measure process, which agrees with simulations by two-dimensional (axisymmetric) particle-in-cell code LCODE about 5%. agreement achieved in population scans two selected plasma densities and scan longitudinal density gradient. reached only case wide enough simulation box (several...
The advanced wakefield experiment (AWAKE) at CERN is the first proton beam-driven plasma acceleration experiment. main goal of AWAKE RUN 1 was to demonstrate seeded self-modulation (SSM) beam and electron witness in wakefield. For experiment, a 10-meter-long Rubidium-vapor cell together with high-power laser for ionization used generate plasma. driven by 400 GeV/c extracted from super synchrotron (SPS), which undergoes process probe wakefields generated an S-band RF photo-cathode gun then...