title: Design and optimization of a parallel spectrometer for ultra-fast X-ray science.
abstract: In the present work, different varied line space (VLS) and reflection zone plate (RZP) gratings are analyzed for their suitability in low-signal femtosecond soft X-ray spectroscopy. The need for high efficiency suggests a straightened focal line whose sharpness and residual curvature will determine the quality. One- and two-dimensional VLS structures feature an attractive trade-off between a sufficient optical performance and a strongly relaxed fabrication, due to moderate line densities which are easily accessible by e-beam lithography. Based on fanned-out RZP arrays, their continuous limit version is identified to generate an almost perfect focal line however, with an aberration level three orders of magnitude better than for the VLS gratings and well below the diffraction limit over large acceptance angles.
authors.forename: Christoph
authors.initials: C
authors.lastname: Braig
authors.forename: Heike
authors.initials: H
authors.lastname: Löchel
authors.forename: Rolf
authors.initials: R
authors.lastname: Mitzner
authors.forename: Wilson
authors.initials: W
authors.lastname: Quevedo
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Loukas
authors.forename: Markus
authors.initials: M
authors.lastname: Kubin
authors.forename: Christian
authors.initials: C
authors.lastname: Weniger
authors.forename: Alexander
authors.initials: A
authors.lastname: Firsov
authors.forename: Jens
authors.initials: J
authors.lastname: Rehanek
authors.forename: Maria
authors.initials: M
authors.lastname: Brzhezinskaya
authors.forename: Philippe
authors.initials: P
authors.lastname: Wernet
authors.forename: Alexander
authors.initials: A
authors.lastname: Föhlisch
authors.forename: Alexei
authors.initials: A
authors.lastname: Erko