Hard x-ray broad band Laue lenses (80-600 keV): building methods and performances

Abstract

We present the status of the laue project devoted to develop a technology for building a 20 meter long focal length Laue lens for hard X-/soft gamma-ray astronomy (80-600 keV). The Laue lens is composed of bent crystals of Gallium Arsenide (GaAs, 220) and Germanium (Ge, 111), and, for the first time, the focusing property of bent crystals has been exploited for this field of applications. We show the preliminary results concerning the adhesive employed to fix the crystal tiles over the lens support, the positioning accuracy obtained and possible further improvements. The Laue lens petal that will be completed in a few months has a pass band of 80-300 keV and is a fraction of an entire Laue lens capable of focusing X-rays up to 600 keV, possibly extendable down to ∼20-30 keV with suitable low absorption crystal materials and focal length. The final goal is to develop a focusing optics that can improve the sensitivity over current telescopes in this energy band by 2 orders of magnitude.

Focusing diffraction optics for orbital telescopes

“…Therefore, the development of a technique for assembly of a large number of crystals into a lens with an adequate alignment accuracy is of key importance [174]. The methods for assembly and alignment of crystals have been reviewed in [176,[224][225][226][227][228].…”

Understanding the origin of the positron annihilation line and the physics of supernova explosions

“…In the current design the crystal tiles have a 30×10 mm 2 cross section, and a 2 mm thickness. Bent crystals have been produced and a technology for an accurate alignment (the requirement is a misalignment < 10 arcsec) of the crystal tiles in the lens has been identified [79] 10 see Fig. 16 a Total geometric area through the mask or collimator Important features of the proposed lens are its energy passband, angular resolution, and Field of View (FOV).…”