Conference Presentation

PUBDB-2024-01837

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Investigating different placements of the collimating mirror for the PETRA IV beamline AppAnaXAS

Nentwich, M. (Corresponding author)Extern*DESY*

2024

Abstract: PETRA III stands as a premier storage ring X-ray radiation source, offering exceptional capabilities for scientific research. The forthcoming PETRA IV upgrade will further extend the capabilities, empowering researchers to analyze intricate processes occurring within catalysts, batteries, and microchips under realistic operating conditions. The Applied and Analytical quick X-ray Absorption Spectroscopy beamline (AppAnaXAFS), will be one of the first operating beamlines within the second phase of the upgrade, which focuses on the construction and commissioning of the new west hall. The scientific scope of this beamline lies on in-situ and operando analysis of various catalytic processes for efficient conversion among all kinds of application areas, like “energy” (distribution and storage of energy in the form of chemical energy carriers), “green chemistry” (to close the carbon cycle), “earth & environment” (bio-catalysis as part of biotechnology), and “air & space transportation” (synthetic fuels).Especially for the quick-EXAFS measurements a source with a broad and continuous spectrum is favorable, which is why the use of a 3-pole Wiggler is intended. However, this Wiggler comes at the cost of high divergence and an imminent loss of intensity at various “obstacles” along the beamline, e.g. photon shutters and monochromator. To reduce this loss as much as possible, the use of a collimating mirror before the monochromator is desired. Generally, optical elements like mirrors are placed outside the tunnels to ensure easy maintenance. For PETRA IV, the placement closest to the source, but outside the tunnel would be at 42 m. Discussions with the responsible vacuum group revealed a possible position of collimating mirrors at 22 m within the tunnel.In order to evaluate the advantages and disadvantages of the different mirror positions, an extensive x-ray tracing study was performed, considering not only the mirror position, but also different geometries (parabolic, toroidal, bent), lengths, coatings, and two different Wiggler settings.

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Contributing Institute(s):

1. Experimentebetreuung PETRA III (FS-PET-D)
2. Experimentebetreuung PETRA III (FS-PET-S)

Research Program(s):

1. 631 - Matter – Dynamics, Mechanisms and Control (POF4-631) (POF4-631)
2. EURIZON - European network for developing new horizons for RIs (871072) (871072)

Experiment(s):

1. PETRA Beamline P23 (PETRA III)
2. PETRA Beamline P65 (PETRA III)

Appears in the scientific report 2024

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