Eur.XFEL

 2019-07-1210:44 [PUBDB-2019-02698] Journal Article et al Evidence of Extreme Ultraviolet Superfluorescence in Xenon Physical review letters 123(2), 023201 (2019) [10.1103/PhysRevLett.123.023201]   We present a comprehensive experimental and theoretical study on superfluorescence in the extreme ultraviolet wavelength regime. Focusing a free-electron laser pulse in a cell filled with Xe gas, the medium is quasi-instantaneously population inverted by 4d-shell ionization on the giant resonance followed by Auger decay [...] OpenAccess: PDF PDF (PDFA); 2019-06-2911:40 [PUBDB-2019-02611] Journal Article et al New dynamic diamond anvil cells for tera-pascal per second fast compression x-ray diffraction experiments Review of scientific instruments 90(6), 065114 (2019) [10.1063/1.5098993]   Fast compression experiments performed using dynamic diamond anvil cells (dDACs) employing piezoactuators offer the opportunity to study compression-rate dependent phenomena. In this paper, we describe an experimental setup which allows us to perform time-resolved x-ray diffraction during the fast compression of materials using improved dDACs. [...] Published on 2019-06-21. Available in OpenAccess from 2020-06-21.: PDF PDF (PDFA); 2019-06-2110:30 [PUBDB-2019-02527] Journal Article et al Two-color XUV+NIR femtosecond photoionization of neon in the near-threshold region New journal of physics 21(6), 063034 (2019) [10.1088/1367-2630/ab2a98]   Results of angle-resolved electron spectroscopy of near-threshold photoionization of Ne atoms bycombined femtosecond extreme ultraviolet and near infraredfields are presented. The dressed-electron spectra show an energetic distribution into so-called sidebands, being separated by thephoton energy of the dressing laser [...] OpenAccess: PDF PDF (PDFA); 2019-05-1616:20 [PUBDB-2019-02299] Journal Article/Report Tomin, S. Accelerator Beam Dynamics at the European X-Ray Free Electron Laser [DESY-18-178]   We consider the collective beam dynamics in the accelerator of the European X-ray Free Electron Laser for electron bunches with charges of 250 and 500 pC. The dynamics has been studied numerically with different computer programs, and we struggle to include properly the whole beam physics with collective effects. [...] OpenAccess: PDF PDF (PDFA); 2019-05-0809:15 [PUBDB-2019-02178] Journal Article et al Photon diagnostics at the FLASH THz beamline Journal of synchrotron radiation 26(3), 700 - 707 (2019) [10.1107/S1600577519003412]   The THz beamline at FLASH, DESY, provides both tunable (1–300 THz) narrow-bandwidth (∼10%) and broad-bandwidth intense (up to 150 uJ) THz pulses delivered in 1 MHz bursts and naturally synchronized with free-electron laser X-ray pulses. Combination of these pulses, along with the auxiliary NIR and VIS ultrashort lasers, supports a plethora of dynamic investigations in physics, material science and biology. [...] OpenAccess: PDF PDF (PDFA); 2019-04-0213:22 [PUBDB-2019-01807] Journal Article et al In situ stability of carbonates in presence of mantle phases OpenAccess: PDF PDF (PDFA); 2019-02-1314:30 [PUBDB-2019-01075] Journal Article et al The Adaptive Gain Integrating Pixel Detector at the European XFEL Journal of synchrotron radiation 26(1), 74 - 82 (2019) [10.1107/S1600577518016077]   The Adaptive Gain Integrating Pixel Detector (AGIPD) is an X-ray imager, custom designed for the European X-ray Free-Electron Laser (XFEL). It is a fast, low-noise integrating detector, with an adaptive gain amplifier per pixel. [...] OpenAccess: PDF PDF (PDFA); 2019-02-1210:13 [PUBDB-2019-01056] Journal Article et al Ultrafast structural dynamics of photo-reactions observed by time-resolved x-ray cross-correlation analysis Structural dynamics 6(2), 024301 (2019) [10.1063/1.5086374]   We applied angular X-ray Cross-Correlation analysis (XCCA) to scattering images from a femtosecond resolution X-ray free-electron laser pump-probe experiment with solvated PtPOP {[Pt$_2$(P$_2$O$_5$H$_2$)$_4$]$^{4–}$} metal complex molecules. The molecules were pumped with linear polarized laser pulses creating an excited state population with a preferred orientational (alignment) direction [...] OpenAccess: PDF PDF (PDFA); 2019-01-3015:23 [PUBDB-2019-00875] Journal Article et al Roadmap of ultrafast x-ray atomic and molecular physics Journal of physics / B 51(3), 032003 (2018) [10.1088/1361-6455/aa9735]   X-ray free-electron lasers (XFELs) and table-top sources of x-rays based upon high harmonic generation (HHG) have revolutionized the field of ultrafast x-ray atomic and molecular physics, largely due to an explosive growth in capabilities in the past decade. XFELs now provide unprecedented intensity (1020 W cm−2) of x-rays at wavelengths down to ~1 Ångstrom, and HHG provides unprecedented time resolution (~50 attoseconds) and a correspondingly large coherent bandwidth at longer wavelengths [...] OpenAccess: PDF PDF (PDFA); 2019-01-3015:18 [PUBDB-2019-00874] Journal Article et al Stimulated X-Ray Emission Spectroscopy in Transition Metal Complexes Physical review letters 120(13), 133203 (2018) [10.1103/PhysRevLett.120.133203]   We report the observation and analysis of the gain curve of amplified $Kα$ x-ray emission from solutions of Mn(II) and Mn(VII) complexes using an x-ray free electron laser to create the $1s$ core-hole population inversion. We find spectra at amplification levels extending over 4 orders of magnitude until saturation [...] OpenAccess: PDF PDF (PDFA);