0587353 - FZÚ 2025 RIV US eng J - Journal Article
Keitel, B. - Chalupský, Jaromír - Jelínek, Šimon - Burian, Tomáš - Dziarzhytski, S. - Hájková, Věra - Juha, Libor - Kuglerová, Zuzana - Kuhlmann, M. - Mann, K. - Ruiz-Lopez, M. - Schaefer, B. - Vozda, Vojtěch - Wodzinski, T. - Yurkov, M. V. - Plönjes, E.
Comparison of wavefront sensing and ablation imprinting for FEL focus diagnostics at FLASH2.
Optics Express. Roč. 32, č. 12 (2024), s. 21532-21552. ISSN 1094-4087
R&D Projects: GA ČR(CZ) GA20-08452S; GA MŠMT(CZ) LM2023068
Institutional support: RVO:68378271
Keywords : ablation imprinting * FEL focus diagnostics * FLASH2 * Hartmann wavefront sensor
OECD category: Optics (including laser optics and quantum optics)
Impact factor: 3.2, year: 2023 ; AIS: 0.723, rok: 2023
Method of publishing: Open access
DOI: https://doi.org/10.1364/OE.527418

Extreme ultraviolet (EUV) photon beam characterization techniques, Hartmann wavefront sensing and single shot ablation imprinting, were compared along the caustic of a tightly focused free-electron laser (FEL) beam at beamline FL24 of FLASH2, the Free-electron LASer in Hamburg at DESY. The transverse coherence of the EUV FEL was determined by a Young’s double pinhole experiment and used in a back-propagation algorithm which includes partial coherence to calculate the beam intensity profiles along the caustic from the wavefront measurements. A very good agreement of the profile structure and size is observed for different wavelengths between the back-propagated profiles, an indirect technique, and ablation imprints. As a result, the Hartmann wavefront sensor including its software MrBeam is a very usefull, single shot pulse resolved and fast tool for non-invasive determination of focal spot size and shape and also for beam profiles along the caustic.
Permanent Link: https://hdl.handle.net/11104/0360253