# FS-FLASH

 2017-11-2917:42 [PUBDB-2017-12552] Contribution to a conference proceedings/Contribution to a book et al Experience with Multi-Beam and Multi-Beamline FEL-Operation 8th International Particle Accelerator Conference, IPAC17, Meeting locationCopenhagen, Denmark, 15 May 2017 - 19 May 2017 2615-2617 (2017) DESY’s free-electron laser FLASH provides soft X-raypulses for scientific users at wavelengths down to 4 nm simultaneously in two undulator beamlines. They are driven by a common linear superconducting accelerator with a beamenergy of up to 1.25 GeV. [...] Restricted: PDF PDF (PDFA); External link: Fulltext 2017-11-2917:27 [PUBDB-2017-12551] Journal Article et al Experience with Multi-Beam and Multi-Beamline FEL-Operation   DESY’s free-electron laser FLASH provides soft X-ray pulses for scientific usersat wavelengths down to 4 nm simultaneously in two undulator beamlines. They are drivenby a common linear superconducting accelerator with a beam energy of up to 1.25 GeV. [...] OpenAccess: PDF PDF (PDFA); 2017-11-0818:42 [PUBDB-2017-11787] Journal Article et al The FLASH Facility: Advanced Options for FLASH2 and Future Perspectives Applied Sciences 7(11), 1114 (2017) [10.3390/app7111114]   Since 2016, the two free-electron laser (FEL) lines FLASH1 and FLASH2 have been run simultaneously for users at DESY in Hamburg. With the installation of variable gap undulators in the new FLASH2 FEL line, many new possibilities have opened up in terms of photon parameters for experiments. [...] OpenAccess: PDF PDF (PDFA); 2017-11-0814:32 [PUBDB-2017-11770] Contribution to a conference proceedings/Contribution to a book et al First Operation of a Harmonic Lasing Self-Seeded FEL 38th International Free Electron Laser Conference, FEL 2017, Meeting locationSanta Fe, USA, 20 Aug 2017 - 25 Aug 2017 4 pp. (2017) [10.3204/PUBDB-2017-11770]   Harmonic lasing is a perspective mode of operation of X-ray FEL user facilities that provide brilliant beams of higher energy photons for user experiments. Another useful application of harmonic lasing is so called Harmonic Lasing Self-Seeded Free Electron Laser (HLSS FEL) that improves spectral brightness of these facilities. [...] OpenAccess: PDF PDF (PDFA); 2017-09-1316:13 [PUBDB-2017-10736] Contribution to a conference proceedings/Contribution to a book et al Concept for a Seeded FEL at FLASH2 8th Intl. Particle Accelerator Conference, IPAC2017, Meeting locationCopenhagen, Denmark, 14 May 2017 - 19 May 2017 Geneva : JACoW, 2607-2610 (2017) [10.18429/JACoW-IPAC2017-WEPAB019]   The free-electron laser (FEL) FLASH is a user facility delivering photon pulses down to 4 nm wavelength. Recently, the second FEL undulator beamline FLASH2 was added to the facility. [...] OpenAccess: PDF PDF (PDFA); 2017-09-1214:07 [PUBDB-2017-10683] Journal Article et al Real-Time Elucidation of Catalytic Pathways in CO Hydrogenation on Ru The journal of physical chemistry letters 8(16), 3820 - 3825 (2017) [10.1021/acs.jpclett.7b01549]   The direct elucidation of the reaction pathways in heterogeneous catalysis has been challenging due to the short-lived nature of reaction intermediates. Here, we directly measured on ultrafast time scales the initial hydrogenation steps of adsorbed CO on a Ru catalyst surface, which is known as the bottleneck reaction in syngas and CO$_2$ reforming processes. [...] Published on 2017-07-31. Available in OpenAccess from 2018-07-31.: CO Hydrogenation Supplemental 2017.07.28 - Resubmitted JPCL - PDF PDF (PDFA); CO Hydrogenation 2017.07.30 - Resubmitted JPCL - PDF PDF (PDFA); Restricted: PDF PDF (PDFA); 2017-09-0423:48 [PUBDB-2017-10311] Journal Article et al Direct 3D mapping of the Fermi surface and Fermi velocity Nature materials 16(6), 615 - 621 (2017) [10.1038/nmat4875]   We performed a full mapping of the bulk electronic structure including the Fermi surface and Fermi-velocity distribution v$_F$(k$_F$) of tungsten. The 4D spectral function ρ(E$_B$; k) in the entire bulk Brillouin zone and 6 eV binding-energy (E$_B$) interval was acquired in ~3 h thanks to a new multidimensional photoemission data-recording technique (combining full-field k-microscopy with time-of-flight parallel energy recording) and the high brilliance of the soft X-rays used. [...] Restricted: PDF PDF (PDFA); 2017-08-3013:56 [PUBDB-2017-10147] Contribution to a conference proceedings/Contribution to a book et al First Operation of a Harmonic Lasing Self-Seeded FEL 8th International Particle Accelerator Conference, IPAC17, Meeting locationCopenhagen, Denmark, 15 May 2017 - 19 May 2017 Geneva : JACoW, 2621-2624 (2017) [10.18429/JACoW-IPAC2017-WEPAB023]   Harmonic lasing is a perspective mode of operation of X-ray FEL user facilities that allows to provide brilliant beams of higher energy photons for user experiments. Another useful application of harmonic lasing is so called Harmonic Lasing Self-Seeded Free Electron Laser (HLSS FEL) that allows to improve spectral brightness of these facilities. [...] OpenAccess: PDF PDF (PDFA); Restricted: PDF PDF (PDFA); External link: Fulltext 2017-06-2310:06 [PUBDB-2017-05924] Journal Article et al Statistical properties of a free-electron laser revealed by Hanbury Brown?Twiss interferometry Physical review / A 95(2), 023843 (2017) [10.1103/PhysRevA.95.023843]   We present a comprehensive experimental analysis of statistical properties of the self-amplified spontaneous emission free-electron laser (FEL) FLASH by means of Hanbury Brown and Twiss interferometry. The experiments were performed at FEL wavelengths of 5.5, 13.4, and 20.8 nm [...] OpenAccess: PDF PDF (PDFA); 2017-06-0817:06 [PUBDB-2017-04558] Journal Article et al Communication: Direct evidence for sequential dissociation of gas-phase Fe(CO)$_5$ via a singlet pathway upon excitation at 266 nm The journal of chemical physics 146(21), 211103 (2017) [10.1063/1.4984774]   We prove the hitherto hypothesized sequential dissociation of Fe(CO)$_5$ in the gas phase upon photoexcitation at 266 nm via a singlet pathway with time-resolved valence and core-level photoelectron spectroscopy with an x-ray free-electron laser. Valence photoelectron spectra are used to identify free CO molecules and to determine the time constants of stepwise dissociation to Fe(CO)$_4$ within the temporal resolution of the experiment and further to Fe(CO)$_3$ within 3 ps [...] OpenAccess: PDF PDF (PDFA);