Laue lenses: Focusing optics for hard X/soft Gamma-ray Astronomy

TL;DR

Laue lenses, utilizing crystal diffraction, offer a promising approach to focus hard X-/soft Gamma-rays, potentially overcoming current limitations in sensitivity and imaging for astrophysical observations above 70 keV.

Contribution

This paper presents the concepts, technological developments, and progress in constructing the first prototype of a Laue lens sector with bent Germanium crystals, advancing its readiness for astrophysical use.

Findings

Development of a broad-band Laue lens model

Design and construction of a prototype lens sector

Advancement in crystal bending technology for focusing optics

Abstract

Hard X-/soft Gamma-ray astronomy is a key field for the study of important astrophysical phenomena such as the electromagnetic counterparts of gravitational waves, gamma-ray bursts, black holes physics and many more. However, the spatial localization, imaging capabilities and sensitivity of the measurements are strongly limited for the energy range $>$70 keV due to the lack of focusing instruments operating in this energy band. A new generation of instruments suitable to focus hard X-/ soft Gamma-rays is necessary to shed light on the nature of astrophysical phenomena which are still unclear due to the limitations of current direct-viewing telescopes. Laue lenses can be the answer to those needs. A Laue lens is an optical device consisting of a large number of properly oriented crystals which are capable, through Laue diffraction, of concentrating the radiation into the common Laue lens focus. In contrast with the grazing incidence telescopes commonly used for softer X-rays, the transmission configuration of the Laue lenses allows us to obtain a significant sensitive area even at energies of hundreds of keV. At the University of Ferrara we are actively working on the modelization and construction of a broad-band Laue lens. In this work we will present the main concepts behind Laue lenses and the latest technological developments of the TRILL (Technological Readiness Increase for Laue Lenses) project, devoted to the advancement of the technological readiness of Laue lenses by developing the first prototype of a lens sector made of cylindrical bent crystals of Germanium.