English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Crystals are the elementary constituents of Laue lenses, an emergingtechnology which could allow the realization of a space borne telescope 10 to100 times more sensitive than existing ones in the 100 keV - 1.5 MeV energyrange. This study addresses the current endeavor to the development ofefficient crystals for the realization of a Laue lens.  In the theoretical part 35 candidate-crystals both pure and two-componentsare considered. Their peak reflectivity at 100 keV, 500 keV and 1 MeV iscalculated assuming they are mosaic crystals. It results that a carefulselection of crystals can allow a reflectivity above 30% over the whole energyrange, and even reaching 40% in its lower part. Experimentally, we concentratedon three different materials (Si_{1-x}Ge_x with gradient of composition, mosaicCu and Au) that have been measured both at ESRF and ILL usinghighly-monochromatic beams ranging from 300 keV up to 816 keV. The aim was tocheck their homogeneity, quality and angular spread (mosaicity). These crystalshave shown outstanding performance such as reflectivity up to 31% at ~600 keV(Au) or 60% at 300 keV (SiGe) and angular spread as low as 15 arcsec for Cu,fulfilling very well the requirements for a Laue lens application.Unexpectedly, we also noticed important discrepancies with Darwin's model whena crystal is measured using various energies.

Experimental and theoretical study of diffraction properties of various crystals for the realization of a soft gamma-ray Laue lens