出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：The Gamma Ray Imager (GRI) mission is a concept that was elaborated by a large international
consortium and proposed to ESA in the framework of the Cosmic Vision first announcement of
opportunity in 2007. The aim was simple: to beat the instrumental background in order to get a
sensitivity improvement of at least one order of magnitude with respect to existing instruments
in the very difficult hard X-ray / soft gamma domain. The result of this study was a design
for a focusing telescope based on innovative optics, depth-graded multilayer mirrors to cover the
energy range from 20 to 250 keV and a Laue lens to take over from 220 keV up to 1.3MeV. GRI’s
estimated performance is a continuum sensitivity (DE = E/2) better than 10−7 ph/s/cm2/keV for
100 ks exposure time and an angular resolution of the order of 30 arcsec in a 5 arcmin field of
view. In this paper, we go further in the study of the concept, demonstrating that the Laue lens
is fully transparent to polarization, making the telescope a perfect instrument for polarimetric
studies since the focal plane is an assembly of finely pixelated detector planes, ideal to perform
Compton scattering polarimetry.
