title: Bent crystal spectrometer for both frequency and wavenumber resolved x-ray scattering at a seeded free-electron laser.
abstract: We present a cylindrically curved GaAs x-ray spectrometer with energy resolution ΔE/E = 1.1 × 10(-4) and wave-number resolution of Δk/k = 3 × 10(-3), allowing plasmon scattering at the resolution limits of the Linac Coherent Light Source (LCLS) x-ray free-electron laser. It spans scattering wavenumbers of 3.6 to 5.2/Å in 100 separate bins, with only 0.34% wavenumber blurring. The dispersion of 0.418 eV/13.5 μm agrees with predictions within 1.3%. The reflection homogeneity over the entire wavenumber range was measured and used to normalize the amplitude of scattering spectra. The proposed spectrometer is superior to a mosaic highly annealed pyrolytic graphite spectrometer when the energy resolution needs to be comparable to the LCLS seeded bandwidth of 1 eV and a significant range of wavenumbers must be covered in one exposure.
authors.affiliation: Institute of Optics and Quantum Electronics, Friedrich-Schiller University Jena, Max-Wien-Platz 1, 07743 Jena, Germany.
authors.forename: Ulf
authors.initials: U
authors.lastname: Zastrau
authors.affiliation: Stanford Linear Accelerator Center (SLAC), 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: Luke B
authors.initials: LB
authors.lastname: Fletcher
authors.affiliation: Institute of Optics and Quantum Electronics, Friedrich-Schiller University Jena, Max-Wien-Platz 1, 07743 Jena, Germany.
authors.forename: Eckhart
authors.initials: E
authors.lastname: Förster
authors.affiliation: Stanford Linear Accelerator Center (SLAC), 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: Eric Ch
authors.initials: ECh
authors.lastname: Galtier
authors.affiliation: Stanford Linear Accelerator Center (SLAC), 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: Eliseo
authors.initials: E
authors.lastname: Gamboa
authors.affiliation: Stanford Linear Accelerator Center (SLAC), 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: Siegfried H
authors.initials: SH
authors.lastname: Glenzer
authors.affiliation: Stanford Linear Accelerator Center (SLAC), 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: Philipp
authors.initials: P
authors.lastname: Heimann
authors.affiliation: Institute of Optics and Quantum Electronics, Friedrich-Schiller University Jena, Max-Wien-Platz 1, 07743 Jena, Germany.
authors.forename: Heike
authors.initials: H
authors.lastname: Marschner
authors.affiliation: Stanford Linear Accelerator Center (SLAC), 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: Bob
authors.initials: B
authors.lastname: Nagler
authors.affiliation: Stanford Linear Accelerator Center (SLAC), 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: Andreas
authors.initials: A
authors.lastname: Schropp
authors.affiliation: Institute of Optics and Quantum Electronics, Friedrich-Schiller University Jena, Max-Wien-Platz 1, 07743 Jena, Germany.
authors.forename: Ortrud
authors.initials: O
authors.lastname: Wehrhan
authors.affiliation: Stanford Linear Accelerator Center (SLAC), 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: Hae Ja
authors.initials: HJ
authors.lastname: Lee