A5040221015- Particle Accelerators and Free-Electron Lasers
- Particle accelerators and beam dynamics
- Advanced X-ray Imaging Techniques
- Superconducting Materials and Applications
- Gyrotron and Vacuum Electronics Research
- Advanced Electron Microscopy Techniques and Applications
- Particle Detector Development and Performance
- Advanced Surface Polishing Techniques
- Advancements in Photolithography Techniques
- Scientific Computing and Data Management
- Crystallography and Radiation Phenomena
- Adrenal and Paraganglionic Tumors
- Pulsed Power Technology Applications
- Electron and X-Ray Spectroscopy Techniques
- X-ray Spectroscopy and Fluorescence Analysis
- Lightning and Electromagnetic Phenomena
- Aerodynamics and Acoustics in Jet Flows
- Engineering Technology and Methodologies
- Advanced machining processes and optimization
- Laser-Plasma Interactions and Diagnostics
- Laser Design and Applications
- Archaeological Research and Protection
- Combustion and flame dynamics
- Advanced Data Storage Technologies
- Distributed and Parallel Computing Systems
Deutsches Elektronen-Synchrotron DESY
2019-2024
European X-Ray Free-Electron Laser
2017-2020
Kurchatov Institute
2010-2014
Abstract High-resolution X-ray spectroscopy in the sub-nanosecond to femtosecond time range requires ultrashort pulses and a spectral flux considerably larger than that presently available. free-electron laser (XFEL) radiation from hard self-seeding (HXRSS) setups has been demonstrated past offers necessary peak properties. So far, these systems could not provide high repetition rates enabling average flux. We report results for cascaded HXRSS system installed at European XFEL, currently...
X-ray pump/X-ray probe applications are made possible at Free Electron Laser (XFEL) facilities by generating two pulses with different wavelengths and controllable temporal delay. In order to enable this capability the European XFEL, an upgrade project equip soft SASE3 beamline a magnetic chicane is underway. present paper we describe status of project, its scientific focus expected performance, including start-to-end simulations photon beam transport up sample, as well recent experimental...
We demonstrate that x-ray fluorescence emission, which cannot maintain a stationary interference pattern, can be used to obtain images of structures by recording photon-photon correlations in the manner stellar intensity interferometry Hanbury Brown and Twiss. This is achieved utilizing femtosecond-duration pulses hard free-electron laser generate emission exposures comparable coherence time fluorescence. Iterative phasing photon correlation map generated model-free real-space image...
Modeling of large-scale research facilities is extremely challenging due to complex physical processes and engineering problems. Here, we adopt a data-driven approach model the longitudinal phase-space-diagnostic beamline at photoinector European XFEL with an encoder-decoder neural-network model. A deep convolutional neural network (decoder) used build images, measured on screen, from small feature map generated by another (encoder). We demonstrate that model, trained only experimental data,...
The output power of a free electron laser (FEL) has extremely high variance even when all FEL parameter set points are held constant because the stochastic nature self-amplified spontaneous emission (SASE) process, drift thousands coupled parameters, such as thermal drifts, and uncertainty time variation distribution coming off photo cathode entering accelerator. In this work, we demonstrate application automatic, model-independent feedback for maximization average pulse energy light...
Time-resolved diagnostics at free-electron laser (FEL) facilities, in particular electron beam longitudinal phase space (LPS) and FEL power profile measurements, provide information highly valuable for users, machine development studies, setup. We investigate the slice energy resolution of passive streaker setups, effect an chirp on measured spread. Downstream hard x-ray SASE2 beamline European XFEL, these measurements are enabled by a single-plate nonmovable wakefield streaker, essentially...
We consider the collective beam dynamics in accelerator of European X-ray Free Electron Laser for electron bunches with charges 250 and 500 pC. The has been studied numerically different computer programs, we struggle to include properly whole physics effects. Several scenarios longitudinal are considered peak currents 5 10 kA. A procedure choice machine parameters is described, tolerances radio frequency accelerating modules along calculated. bunch properties at end before undulator line...
For modern linac- and storage-ring-based light sources certain amount of empirical tuning is used to reach ultimate performance. The possibility perform such by automatic methods has now been demonstrated several authors (e.g. I.Agapov et al. in proc IPAC 2015). In this paper we present the progress development our optimisation software based on OCELOT its applications SASE FEL optimization at FLASH LCLS, potential for storage ring optimization.
Undulator tapering controls the resonance properties of free-electron laser (FEL) amplification process. Wakefield energy losses in an undulator’s vacuum chamber are one factors that determine linear taper. While another contribution to losses, namely due spontaneous radiation, can be calculated analytically, estimating wakefield requires detailed knowledge geometry and electron beam current profile. We introduce a method for automatic estimation which leverages noninvasive THz diagnostics,...
Abstract Plasma and beam physics are usually considered as classical disciplines with quantum effects featuring only rarely. In particular, free electron lasers (FELs) even in the Angstrom regime (developed recently being upgraded towards shorter wavelengths) well described by mechanics electrodynamics. There is, however, a effect that can influence operation of these devices limit shortest achievable wavelength, namely energy diffusion an due to fluctuations undulator radiation. Although...
We present measurements of slice energy spread at the injector section European X-Ray Free Electron Laser for an electron bunch with charge 250 pC. Two methods considered in paper are based on dispersive after a transverse deflecting structure (TDS). The first approach uses different beam energies. show that proper scaling TDS voltage rms error measurement is less than 0.3 keV 6 keV. In second we demonstrate keeping constant but adjusting only optics able to simplify complexity and reduce...
Abstract The European XFEL is currently the only high-repetition rate hard X-ray free electron laser (FEL) facility in operation worldwide. We significantly improved its capabilities by installing a cascaded Hard Self-Seeding (HXRSS) system, composed of two single-crystal monochromators. With this mJ-level pulses photon energy range 6 -14keV with bandwidth around 1eV (corresponding to about 1mJ/eV spectral density) were generated. Combined burst-mode, multi-MHz repetition accelerator, HXRSS...
Existing FEL facilities often suffer from stability issues: so electron orbit, transverse optics, bunch compression and other parameters have to be readjusted account for drifts in performance of various components. The tuning procedures typically employed operation are manual lengthy. We been developing a combination model-free model-based automatic methods meet the needs present upcoming XFEL facilities. Our approach has implemented at FLASH \cite{flash} achieve SASE using empirical...
FEL tuning and optimization within the OCELOT framework has been implemented in 2015 since used for SASE pulse energy at FLASH later LCLS, as well injection efficiency maximization Siberia-1 storage ring. For European XFEL commissioning purposes code was considerably improved additional set of tools introduced. Here these experi-ence their use during initial operation will be presented. Future devel-opment directions outlined.
In this contribution we present an analysis of electron trajectories in the three dimensional magnetic field from a planar undulator. The differential equations motion are analytically solved by means perturbation theory approach, and expressions for electrons derived, without recourse to averaging over undulator period. All small terms up third order inclusive obtained. Analytically calculated excellent agreement with those computed numerically specially written code.