MEDSI2018 - List of Authors (Birri, M.)

Paper	Title	Page
THPH04	Fast X-Ray Beam Intensity Stabilization for Absorption Spectroscopy and Spectromicroscopic Imaging	343
	M. Birri, D. Ferreira Sanchez, D. Grolimund, B. Meyer, V.A. Samson PSI, Villigen PSI, Switzerland
	The characteristics of synchrotron sources and beamline optics commonly result in systematic and random variations of the delivered photon flux. In X-ray absorption based measurements, for example, monochromator glitches [1] or the energy dependent gap size of small gap in-vacuum undulators [2] are intrinsic sources for changes in the intensity of the incoming photon flux (I0), however many types of x-ray experiments would benefit from a constant I0. Monochromator Stabilization (MOSTAB) is a common solution for most synchrotron beamlines with double crystal monochromators. This approach is based on the relative alignment of the two monochromator crystals (dynamic detuning) to stabilize beam intensity or position. Obviously, any change in angular alignment of the monochromator crystals will also induce deviations in the beam trajectory and photon energy distribution. At the microXAS undulator beamline of the SLS, we have implemented a system to achieve a constant I0. Two wedge-shaped absorbers produce a spatially uniform attenuation preserving the beam shape without introducing changes in its trajectory. Hardware, control loop and system performance will be presented. [1] F.Bridges, Nuclear Instruments and Methods in Physics Research A257 (1987) 447-450. [2] H.Kitamura, J.Synchrotron Rad. 7 (2000), 121-130.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-MEDSI2018-THPH04
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Paper

Title

Page

Fast X-Ray Beam Intensity Stabilization for Absorption Spectroscopy and Spectromicroscopic Imaging

343

M. Birri, D. Ferreira Sanchez, D. Grolimund, B. Meyer, V.A. Samson
PSI, Villigen PSI, Switzerland

The characteristics of synchrotron sources and beamline optics commonly result in systematic and random variations of the delivered photon flux. In X-ray absorption based measurements, for example, monochromator glitches [1] or the energy dependent gap size of small gap in-vacuum undulators [2] are intrinsic sources for changes in the intensity of the incoming photon flux (I0), however many types of x-ray experiments would benefit from a constant I0. Monochromator Stabilization (MOSTAB) is a common solution for most synchrotron beamlines with double crystal monochromators. This approach is based on the relative alignment of the two monochromator crystals (dynamic detuning) to stabilize beam intensity or position. Obviously, any change in angular alignment of the monochromator crystals will also induce deviations in the beam trajectory and photon energy distribution. At the microXAS undulator beamline of the SLS, we have implemented a system to achieve a constant I0. Two wedge-shaped absorbers produce a spatially uniform attenuation preserving the beam shape without introducing changes in its trajectory. Hardware, control loop and system performance will be presented.
[1] F.Bridges, Nuclear Instruments and Methods in Physics Research A257 (1987) 447-450.
[2] H.Kitamura, J.Synchrotron Rad. 7 (2000), 121-130.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-MEDSI2018-THPH04

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)