Resonant excitation and spatial distribution of fluorescent X-rays at the output of polycapillary structures

Abstract

Experimental and theoretical studies of the angular X-ray-intensity distribution are performed at the output of microchannel plates under the condition that monochromatic radiation is incident on the microcapillary walls at grazing angles. The primary-radiation angles and energies at which a synchrotronradiation beam excites fluorescent X-rays propagating through polycapillary structures are determined. In the case of X-rays passing through microcapillaries, the fine structure of their spectra is investigated at energies corresponding to the anomalous dispersion region of the SiL 2, 3 and OK absorption edges. Theoretical calculations are carried out using a model involving a transition layer on the microchannel surface.

Design study of a photon beamline for a soft X-ray FEL driven by high gradient acceleration at EuPRAXIA@SPARC_LAB

“…Moreover, multi channel plates (MCPs) can be considered as they offer promising results for coherent X-ray imaging. The MCP parameters are very flexible thus becoming attractive to design novel X-ray optics [9,10] will be possible, exploiting the visibility of an interference pattern from a double slit [11] or, as demonstrated also at SPARC LAB, using the speckle pattern from small spheres [12,13]. We will introduce the slits (or the spheres) in a dedicated chamber after the spectrometer, depicted in section 2.3, and we will use a screen near to the experimental chamber to visualize the pattern.…”