scholarly journals Slice collective dynamics, projected emittance deterioration and free electron laser performances detrimental effects

2020 ◽  
Vol 86 (6) ◽  
Author(s):  
G. Dattoli ◽  
S. Di Mitri ◽  
F. Nguyen ◽  
A. Petralia
Keyword(s):  
Phase Space ◽  
Output Power ◽  
Free Electron ◽  
Free Electron Laser ◽  
Coherence Length ◽  
Electron Bunch ◽  
Laser Intensity ◽  
Beam Transport ◽  
X Ray ◽  
Laser Dynamics

Self-amplified spontaneous emission (SASE) free electron laser (FEL) devices have disclosed an unexpected interplay between the laser intensity growth and regions of the electron bunch of the order of the coherence length. They are usually identified with the bunch slice and contribute to the laser dynamics with their own characteristics. The dynamical effects inducing geometrical and phase space misalignment of bunch slice in X-ray operating FELs can be traced back to a plethora of phenomena, both in the Linac accelerating section or inside the beam transport optic magnet. They are responsible for spoiling of the beam projected qualities and, if not corrected properly, induce an increase of the saturation length and a decreasing of the output power. We discuss the inclusion of these effects in models employing scaling formulae.

scholarly journals The FERMI@Elettra free-electron-laser source for coherent x-ray physics: photon properties, beam transport system and applications

2010 ◽  
Vol 12 (7) ◽  
pp. 075002 ◽  
Author(s):  
E Allaria ◽  
C Callegari ◽  
D Cocco ◽  
W M Fawley ◽  
M Kiskinova ◽  
...  
Keyword(s):  
Transport System ◽  
Free Electron ◽  
Free Electron Laser ◽  
Laser Source ◽  
Beam Transport ◽  
X Ray

scholarly journals The photon beamline vacuum system of the European XFEL

2021 ◽  
Vol 28 (4) ◽  
Author(s):  
Martin Dommach ◽  
Massimiliano Di Felice ◽  
Bianca Dickert ◽  
Denis Finze ◽  
Janni Eidam ◽  
...  
Keyword(s):  
Free Electron ◽  
Free Electron Laser ◽  
Vacuum System ◽  
Entire System ◽  
Scientific Instruments ◽  
Beam Transport ◽  
X Ray ◽  
Laser Facility ◽  
Reliability And Robustness ◽  
Vacuum Systems

The photon beamline vacuum system of the European X-ray Free-Electron Laser Facility (European XFEL) is described. The ultra-large, in total more than 3 km-long, fan-like vacuum system, consisting of three photon beamlines is an essential part of the photon beam transport. It is located between the accelerator vacuum system and the scientific instruments. The main focus of the design was on the efficiency, reliability and robustness of the entire system to ensure the retention of beam properties and the operation of the X-ray optics and X-ray photon diagnostics components. Installation started in late 2014, the first of the three beamline vacuum systems was commissioned in spring 2017, and the last one was operational in mid-2018. The present state and experience from the first years of operation are outlined.

scholarly journals Opportunities for Two-Color Experiments in the Soft X-ray Regime at the European XFEL

2020 ◽  
Vol 10 (8) ◽  
pp. 2728 ◽  
Author(s):  
Svitozar Serkez ◽  
Winfried Decking ◽  
Lars Froehlich ◽  
Natalia Gerasimova ◽  
Jan Grünert ◽  
...  
Keyword(s):  
Free Electron ◽  
Free Electron Laser ◽  
Spectral Properties ◽  
Experimental Results ◽  
Temporal Delay ◽  
Beam Transport ◽  
X Ray ◽  
Expected Performance ◽  
The Status ◽  
On Line

X-ray pump/X-ray probe applications are made possible at X-ray Free Electron Laser (XFEL) facilities by generating two X-ray pulses with different wavelengths and controllable temporal delay. In order to enable this capability at the European XFEL, an upgrade project to equip the soft X-ray SASE3 beamline with a magnetic chicane is underway. In the present paper we describe the status of the project, its scientific focus and expected performance, including start-to-end simulations of the photon beam transport up to the sample, as well as recent experimental results demonstrating two-color lasing at photon energies of 805 eV + 835 eV and 910 eV + 950 eV. Additionally, we discuss methods to analyze the spectral properties and the intensity of the generated radiation to provide on-line diagnostics for future user experiments.

scholarly journals For the generation of an intense isolated pulse in hard X-ray region using X-ray free electron laser

2012 ◽  
Vol 30 (3) ◽  
pp. 397-406 ◽  
Author(s):  
Sandeep Kumar ◽  
Heung-Sik Kang ◽  
Dong-Eon Kim
Keyword(s):  
Free Electron ◽  
Free Electron Laser ◽  
Electron Bunch ◽  
Attosecond Pulse ◽  
Current Profile ◽  
Distribution Profile ◽  
X Ray ◽  
Isolated Attosecond Pulse ◽  
Pump Probe Experiment ◽  
Pal Xfel

AbstractFor a real, meaningful pump-probe experiment with attosecond temporal resolution, an intense isolated attosecond pulse is in demand. For that purpose we report the generation of an intense isolated attosecond pulse, especially in X-ray region using a current-enhanced self-amplified spontaneous emission in a free electron laser (FEL). We use a few cycle laser pulse to manipulate the electron-bunch inside a two-period planar wiggler. In our study, we employ the electron beam parameters of Pohang Accelerator Laboratory (PAL)-XFEL. The RF phase effect of accelerator columns on the longitudinal energy distribution profile and current profile of electron-bunch is also studied, aiming that these results can be experimentally realized in PAL-XFEL. We show indeed that the manipulation of electron-energy bunch profile may lead to the generation of an isolated attosecond hard X-ray pulse: 150 attosecond radiation pulse at 0.1 nm wavelength can be generated.

scholarly journals X-ray photon diagnostics at the European XFEL

2019 ◽  
Vol 26 (5) ◽  
pp. 1422-1431 ◽  
Author(s):  
Jan Grünert ◽  
Marc Planas Carbonell ◽  
Florian Dietrich ◽  
Torben Falk ◽  
Wolfgang Freund ◽  
...  
Keyword(s):  
Free Electron ◽  
Repetition Rate ◽  
Free Electron Laser ◽  
First Year ◽  
X Rays ◽  
Beam Transport ◽  
Beam Position ◽  
X Ray ◽  
Time Period ◽  
Beam Delivery

The European X-ray Free-Electron Laser (European XFEL) (Altarelli et al., 2006; Tschentscher et al., 2017), the world's largest and brightest X-ray free-electron laser (Saldin et al., 1999; Pellegrini et al., 2016), went into operation in 2017. This article describes the as-built realization of photon diagnostics for this facility, the diagnostics commissioning and their application for commissioning of the facility, and results from the first year of operation, focusing on the SASE1 beamline, which was the first to be commissioned. The commissioning consisted of pre-beam checkout, first light from the bending magnets, X-rays from single undulator segments, SASE tuning with many undulator segments, first lasing, optics alignment for FEL beam transport through the tunnel up to the experiment hutches, and finally beam delivery to first users. The beam properties assessed by photon diagnostics throughout these phases included per-pulse intensity, beam position, shape, lateral dimensions and spectral properties. During this time period, the machine provided users with up to 14 keV photon energy, 1.5 mJ pulse energy, 300 FEL pulses per train and 4.5 MHz intra-bunch train repetition rate at a 10 Hz train repetition rate. Finally, an outlook is given into the diagnostic prospects for the future.

scholarly journals A micro channel-cut crystal X-ray monochromator for a self-seeded hard X-ray free-electron laser

2019 ◽  
Vol 26 (5) ◽  
pp. 1496-1502 ◽  
Author(s):  
Taito Osaka ◽  
Ichiro Inoue ◽  
Ryota Kinjo ◽  
Takashi Hirano ◽  
Yuki Morioka ◽  
...  
Keyword(s):  
Free Electron ◽  
Free Electron Laser ◽  
Electron Bunch ◽  
Optical Pulse ◽  
Seed Pulse ◽  
Micro Channel ◽  
Free Electron Lasers ◽  
X Ray ◽  
Optical Delay ◽  
Temporal Overlap

A channel-cut Si(111) crystal with a channel width of 90 µm was developed for achieving reflection self-seeding in hard X-ray free-electron lasers (XFELs). With the crystal a monochromatic seed pulse is produced from a broadband XFEL pulse generated in the first undulator section with an optical delay of 119 fs at 10 keV. The small optical delay allows a temporal overlap between the seed optical pulse and the electron bunch by using a small magnetic chicane for the electron beam placed between two undulator sections. Peak reflectivity reached 67%, which is reasonable compared with the theoretical value of 81%. By using this monochromator, a monochromatic seed pulse without broadband background in the spectrum was obtained at SACLA with a conversion efficiency from a broadband XFEL pulse of 2 × 10−2, which is ∼10 times higher than the theoretical efficiency of transmission self-seeding using a thin diamond (400) monochromator.

Sign in / Sign up

Export Citation Format

Share Document