JACoW is a publisher in Geneva, Switzerland that publishes the proceedings of accelerator conferences held around the world by an international collaboration of editors.
TY - CONF AU - Du, J. AU - Du, X.W. AU - Wang, Q.P. AU - Wang, Z. ED - Schaa, Volker R.W. ED - Bian, Lin ED - Chen, Zhichu ED - Dong, Yuhui ED - He, Ping TI - Influence of the Groove Curvature on the Spectral Resolution in a Varied-Line-Spacing Plane Grating Monochromator (VLS-PGM) J2 - Proc. of MEDSI2023, Beijing, China, 06-10 November 2023 CY - Beijing, China T2 - International Conference on Mechanical Engineering Design of Synchrotron Radiation Equipment and Instrumentation T3 - 12 LA - english AB - Diffraction-limited synchrotron radiation (DLSR) light source with smaller source size and emittance makes ultra-high spectral resolution beamline possible. Here, we report an undulator-based beamline optical design with ultra-high spectral resolution using a varied-line-spacing plane grating monochromator (VLS-PGM), which is a well-proven design for achieving ultra-high resolution in the soft X-ray band. A VLS plane grating with a central groove density of 2400 l/mm is utilized to cover the photon energy region of 250 ~ 2000eV. VLS gratings are generally fabricated using the holographic method, but the resulting grating grooves are two-dimensionally curved curves, which can affect the resolution of the monochromator. To analyse this effect, we first use a spherical wavefront and an aspherical wavefront to generate the fringes and optimized the recording parameters. We also present a method for calculating the groove curvature of holographic plane VLS grating grooves. Furthermore, the influence of grating groove curvature on beamline resolution is theoretically analysed based on the aberration theory of concave grating. PB - JACoW Publishing CP - Geneva, Switzerland SP - 67 EP - 69 KW - photon KW - factory KW - synchrotron KW - target KW - experiment DA - 2024/07 PY - 2024 SN - 2673-5520 SN - 978-3-95450-250-9 DO - doi:10.18429/JACoW-MEDSI2023-TUPYP026 UR - https://jacow.org/medsi2023/papers/tupyp026.pdf ER -