Author: Assmann, R.W.     [Aßmann, R.W.]
Paper Title Page
TUXGBE4 Beam Quality Limitations of Plasma-Based Accelerators 607
 
  • A. Ferran Pousa, R.W. Aßmann
    DESY, Hamburg, Germany
  • A. Martinez de la Ossa
    University of Hamburg, Institut für Experimentalphysik, Hamburg, Germany
 
  Plasma-based accelerators are a promising novel technology that could significantly reduce the size and cost of future accelerator facilities. However, the typical quality and stability of the produced beams is still inferior to the requirements of Free Electron Lasers (FELs) and other applications. We present here our recent work in understanding the limitations of this type of accelerators, particularly on the energy spread and bunch length, and possible mitigating measures for future applications, like the plasma-based FEL in the EuPRAXIA design study.  
slides icon Slides TUXGBE4 [4.910 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUXGBE4  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPMF078 Control of FEL Radiation Properties by Tailoring the Seed Pulses 1444
 
  • V. Grattoni, R.W. Aßmann, J. Bödewadt, I. Hartl, C. Lechner, B. Manschwetus, M.M. Mohammad Kazemi
    DESY, Hamburg, Germany
  • A. Azima, W. Hillert, V. Miltchev, J. Roßbach
    University of Hamburg, Institut für Experimentalphysik, Hamburg, Germany
  • S. Khan, T. Plath
    DELTA, Dortmund, Germany
 
  Seeded free-electron lasers (FELs) produce intense, ultrashort and fully coherent X-ray pulses. These seeded FEL pulses depend on the initial seed properties. Therefore, controlling the seed laser allows tailoring the FEL radiation for phase-sensitive experiments. In this contribution, we present detailed simulation studies to characterize the FEL process and to predict the operation performance of seeded pulses. In addition, we show experimental data on the temporal characterization of the seeded FEL pulses performed at the sFLASH experiment in Hamburg.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF078  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPMF079 An Option to Generate Seeded FEL Radiation for FLASH1 1448
 
  • V. Grattoni, R.W. Aßmann, J. Bödewadt, I. Hartl, C. Lechner, B. Manschwetus, M.M. Mohammad Kazemi
    DESY, Hamburg, Germany
  • W. Hillert, V. Miltchev, J. Roßbach
    University of Hamburg, Institut für Experimentalphysik, Hamburg, Germany
  • S. Khan, T. Plath
    DELTA, Dortmund, Germany
 
  The FLASH free-electron laser (FEL) at DESY is currently operated in self-amplified spontaneous emission (SASE) mode in both beamlines FLASH1 and FLASH2. Seeding offers unique properties for the FEL pulse, such as full coherence, spectral and temporal stability. In this contribution, possible ways to carry the seeded FEL radiation to the user hall are presented with analytical considerations and simulations. For this, components of the sFLASH seeding experiment are used.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF079  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPMF085 Status of the sFLASH Experiment 1471
 
  • C. Lechner, R.W. Aßmann, J. Bödewadt, V. Grattoni, I. Hartl, T. Laarmann, M.M. Mohammad Kazemi, A. Przystawik
    DESY, Hamburg, Germany
  • A. Azima, H.B. Biss, M. Drescher, W. Hillert, L.L. Lazzarino, V. Miltchev, J. Roßbach
    University of Hamburg, Institut für Experimentalphysik, Hamburg, Germany
  • S. Khan, T. Plath
    DELTA, Dortmund, Germany
 
  Funding: This work is supported by the Federal Ministry of Education and Research of Germany within FSP-302 under FKZ 05K13GU4, 05K13PE3, and 05K16PEA.
The sFLASH experiment at the free-electron laser (FEL) FLASH1 is a setup for the investigation of external FEL seeding. Since 2015, the seeding scheme high-gain harmonic generation (HGHG) is being studied. At the end of the seeded FEL, an RF deflector enables time-resolved analysis of the seeded electron bunches while the photon pulses can be characterized using the technique of THz streaking. In this contribution, we present the current configuration of the experiment and give an overview of recent experimental results.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF085  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPMF086 Status of the ARES RF Gun at SINBAD: From its Characterization and Installation towards Commissioning 1474
 
  • B. Marchetti, R.W. Aßmann, S. Baark, F. Burkart, U. Dorda, K. Flöttmann, I. Hartl, J. Hauser, J. Herrmann, M. Hüning, K. Knebel, O. Krebs, G. Kube, W. Kuropka, S. Lederer, F. Lemery, F. Ludwig, D. Marx, F. Mayet, M. Pelzer, I. Peperkorn, F. Poblotzki, S. Pumpe, J. Rothenburg, H. Schlarb, M. Titberidze, G. Vashchenko, T. Vinatier, P.A. Walker, L. Winkelmann, K. Wittenburg, S. Yamin, J. Zhu
    DESY, Hamburg, Germany
 
  The SINBAD facility (Short and INnovative Bunches and Accelerators at DESY) is foreseen to host multiple experiments relating to the production of ultra-short electron bunches and novel high gradient acceleration techniques. The SINBAD-ARES linac will be a conventional S-band linear RF accelerator allowing the production of low charge (0.5 pC - tens pC) ultra-short electron bunches (FWHM length =< 1 fs - few fs) with 100 MeV energy. The installation of the linac will proceed in stages. In this paper we report on the status of the characterization of the ARES RF gun and the installations of the related infrastructure.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF086  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPML035 FELs Driven by Laser Plasma Accelerators Operated with Transverse Gradient Undulators 1615
 
  • F. Jafarinia, R.W. Aßmann, F. Burkart, U. Dorda, C. Lechner, B. Marchetti, R. Rossmanith, P.A. Walker
    DESY, Hamburg, Germany
  • A. Bernhard, R. Rossmanith
    KIT, Karlsruhe, Germany
 
  Laser Plasma Accelerators produce beams with a significantly higher energy spread (up to a few percent) compared to conventional electron sources. The high energy spread increases significantly the gain length when used for an FEL. In order to reduce the gain length of the FEL the Transverse Gradient Undulators (TGUs) instead of conventional undulators were proposed. In this paper the limits of this concept are discussed using a modified Version of the GENESIS program*.
*Zhirong Huang et al., Phys. Rev. Lett., 109, 204801
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPML035  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPML038 Simulation of Phase-Dependent Transverse Focusing in Dielectric Laser Accelerator Based Lattices 1622
SUSPF037   use link to see paper's listing under its alternate paper code  
 
  • F. Mayet, R.W. Aßmann, U. Dorda, W. Kuropka
    DESY, Hamburg, Germany
  • W. Kuropka, F. Mayet
    University of Hamburg, Institut für Experimentalphysik, Hamburg, Germany
 
  Funding: Gordon and Betty Moore Foundation. Grant GBMF4744
The Accelerator on a CHip International Program (ACHIP) funded by the Gordon and Betty Moore Foundation aims to demonstrate a prototype of a fully integrated accelerator on a microchip based on laser-driven dielectric structures until 2021. Such an accelerator on a chip needs all components known from classical accelerators. This includes an electron source, accelerating structures and transverse focusing arrangements. Since the period of the accelerating field is connected to the drive laser wavelength of typically a few microns, not only longitudinal but also transverse effects are strongly phase-dependent even for few femtosecond long bunches. If both the accelerating and focusing elements are DLA-based, this needs to be taken into account. In this work we study in detail the implications of a phase-dependent focusing lattice on the evolution of the transverse phase space of a transported bunch.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPML038  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPML039 First Order Sensitivity Analysis of Electron Acceleration in Dual Grating Type Dielectric Laser Accelerator Structures 1626
 
  • F. Mayet, R.W. Aßmann, U. Dorda, W. Kuropka
    DESY, Hamburg, Germany
  • W. Kuropka, F. Mayet
    University of Hamburg, Institut für Experimentalphysik, Hamburg, Germany
 
  Funding: Gordon and Betty Moore Foundation. Grant GBMF4744
Symmetrically driven dual-grating type DLA (Dielectric Laser Accelerator) linac structures allow for in-channel electric field gradients on the order of GV/m at optical wavelengths. In this work we study the sensitivity of important final beam parameters like mean energy, energy spread and transverse emittance on DLA drive laser as well as input beam parameters. To this end a fast specialized particle tracking code (DLATracker) is used to compute the so called first order sensitivity indices based on a large number of Monte Carlo simulation runs of an exemplary external injection based DLA experiment. The results of this work point out important stability constraints on the drive laser setup and the externally injected electron beam.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPML039  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPML041 Two-Stage Laser-Driven Plasma Acceleration With External Injection for EuPRAXIA 1634
 
  • E.N. Svystun, R.W. Aßmann, U. Dorda, A. Ferran Pousa, T. Heinemann, B. Marchetti, P.A. Walker, M.K. Weikum, J. Zhu
    DESY, Hamburg, Germany
  • A. Ferran Pousa, T. Heinemann, A. Martinez de la Ossa
    University of Hamburg, Hamburg, Germany
  • T. Heinemann
    USTRAT/SUPA, Glasgow, United Kingdom
 
  The EuPRAXIA (European Particle Research Accelerator with eXcellence In Applications) project aims at producing a conceptual design for the worldwide plasma-based accelerator facility, capable of delivering multi-GeV electron beams with high quality. This accelerator facility will be used for various user applications such as compact X-ray sources for medical imaging and high-energy physics detector tests. EuPRAXIA explores different approaches to plasma acceleration techniques. Laser-driven plasma wakefield acceleration with external injection of an RF-generated electron beam is one of the basic research directions of EuPRAXIA. We present studies of electron beam acceleration to GeV energies by a two-stage laser wakefield acceleration with external injection from an RF accelerator. Electron beam injection, acceleration and extraction from the plasma, using particle-in-cell simulations, are investigated.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPML041  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPAF050 Simulations of 3D Charge Density Measurements for Commissioning of the PolariX-TDS 1930
SUSPF104   use link to see paper's listing under its alternate paper code  
 
  • D. Marx, R.W. Aßmann, R.T.P. D'Arcy, B. Marchetti
    DESY, Hamburg, Germany
 
  The prototype of a novel X-band transverse deflection structure, the Polarizable X-band (PolariX) TDS*, is currently being prepared for installation in the FLASHForward beamline** at DESY in early 2019. This structure will have the novel feature of variable polarization of the deflecting mode, allowing bunches to be streaked at any transverse angle, rather than at just one angle as in a conventional cavity. By combining screen profiles from several streaking angles using tomographic reconstruction techniques, the full 3D charge density of a bunch can be obtained***. It is planned to perform this measurement for the first time during commissioning of the structure. In this paper, simulations of this measurement are presented and the effects of jitter are discussed.
*P Craievich et al. paper THPAL068, this conference
**A Aschikhin et al. Nucl. Instr. Meth. Phys. Res. A., vol.806, pp.175-183, 2018
***D Marx et al. J. Phys.: Conf. Ser., vol.874, p.012077, 2017
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEPAF050  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPAF032 Simulation Study of an RF Injector for the LWFA Configuration at EuPRAXIA 3025
 
  • J. Zhu, R.W. Aßmann, A. Ferran Pousa, B. Marchetti, P.A. Walker
    DESY, Hamburg, Germany
 
  The Horizon 2020 Project EuPRAXIA (EuropeanPlasma Research Accelerator with eXcellence In Applications) aims at producing a design report of a highly compact and cost-effective European facility with multi-GeV electron beams using a plasma accelerator. LWFA with external injection from an RF accelerator is one of the most promising configurations. In order to achieve the goal parameters for the 5 GeV, 30 pC electron beam at the entrance of the undulator, a high-quality electron beam with bunch length of less than 10 fs (FWHM) and matched beta functions (~1 mm) at the plasma entrance is required. In addition, from the compactness point of view, the injection energy is desired to be as low as possible. A hybrid compression scheme is considered in this paper and a detailed start-to-end simulation is presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAF032  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPAL068 Status of the Polarix-TDS Project 3808
 
  • P. Craievich, M. Bopp, H.-H. Braun, R. Ganter, T. Kleeb, M. Pedrozzi, E. Prat, S. Reiche, R. Zennaro
    PSI, Villigen PSI, Switzerland
  • R.W. Aßmann, F. Christie, R.T.P. D'Arcy, U. Dorda, M. Foese, P. González Caminal, M. Hoffmann, M. Hüning, R. Jonas, O. Krebs, S. Lederer, V. Libov, B. Marchetti, D. Marx, J. Osterhoff, F. Poblotzki, M. Reukauff, H. Schlarb, S. Schreiber, G. Tews, M. Vogt, A. Wagner
    DESY, Hamburg, Germany
  • N. Catalán Lasheras, A. Grudiev, G. McMonagle, W. Wuensch
    CERN, Geneva, Switzerland
 
  A collaboration between DESY, PSI and CERN has been established to develop and build an advanced modular X-band transverse deflection structure (TDS) system with the new feature of providing variable polarization of the deflecting force. This innovative CERN design requires very high manufacturing precision to guarantee highest azimuthal symmetry of the structure to avoid the deterioration of the polarization of the streaking field. Therefore, the high-precision tuning-free production process developed at PSI for the C-band and X-band accelerating structures will be used for the manufacturing. We summarize in this paper the status of the production of the prototype and the waveguide networks foreseen in the different facilities.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAL068  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPMF001 Beam Dynamics Studies for Beam Focusing and Solenoid Alignment at SINBAD 4026
SUSPF020   use link to see paper's listing under its alternate paper code  
 
  • S. Yamin, R.W. Aßmann, B. Marchetti, J. Zhu
    DESY, Hamburg, Germany
 
  SINBAD (Short INnovative Bunches and Accelerators at DESY) facility under construction at DESY plans to host several experiments for the production of ultra-short bunches and will be a test facility for high-gradient compact novel acceleration techniques. The ARES (Accelerator Research Experiment at SINBAD) linac is foreseen to produce ultra-short bunches to be injected e.g. into Novel Dielectric Laser Acceleration structures or Laser Wake-Field Acceleration experiments. The work presented in this paper is based on optimization of the focusing system consisting of solenoids for the ARES, which have been studied earlier in detail but is revisited for updated beamline. Moreover tolerances for the possible misalignment of solenoids are presented investigating the effect on the beam properties during the gun commissioning.
* J. Zhu, R. Assmann, U. Dorda, B. Marchetti, "Matching sub-fs electron bunches for laser-driven plasma acceleration at SINBAD", Nucl. Instrum. Methods Phys. Res., Sect. A 829, 229 (2016)
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMF001  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPML106 Electron Microscopy Inspired Setup for Single-Shot 4-D Trace Space Reconstruction of Bright Electron Beams 4909
 
  • J. Giner Navarro, D.B. Cesar, P. Musumeci
    UCLA, Los Angeles, California, USA
  • R.W. Aßmann, B. Marchetti, D. Marx
    DESY, Hamburg, Germany
 
  Funding: This work has been partially supported by the National Science Foundation under Grant No. 1549132 and Department of Energy under award No. DE-SC0009914.
In the development of low charge, single-shot diagnostics for high brightness electron beams, Transmission Electron Microscopy (TEM) grids present certain advantages compared to pepper pot masks due to higher beam transmission. In this paper, we developed a set of criteria to optimize the resolution of a point projection image. However, this configuration of the beam with respect to the grid and detector positions implies the measurement of a strongly correlated phase space which entails a large sensitivity to small measurement errors in retrieving the projected emittance. We discuss the possibility of an alternative scheme by inserting a magnetic focusing system in between the grid and the detector, similar to an electron microscope design, to reconstruct the phase space when the beam is focused on the grid.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPML106  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)