We present in this paper a focusing gamma-ray telescope with the goal of addressing the true nature of Type Ia Supernovae ( SNe Ia ) .
This telescope is based on a Laue lens focusing a 100 keV wide energy band centered on 847 keV , which corresponds to a bright line emitted by the decay chain of ^ { 56 } Ni , a radioactive element massively produced during SNe Ia events .
Spectroscopy and light curve measurements of this gamma-ray line allow for a direct measurement of the underlying explosion physics and dynamics , and thus discriminate among the competing models .
However , reaching this goal requires the observation of several events with high detection significance , meaning more powerful telescopes .
The telescope concept we present here is composed of a Laue lens held 30 m from the focal plane instrument ( a compact Compton telescope ) by an extendible mast .
With a 3- \sigma sensitivity of 1.8 \times 10 ^ { -6 } ph/s/cm ^ { 2 } in the 3 % -broadened line at 847 keV ( in 1 Ms observation time ) , dozens of SNe Ia could be detected per year out to \sim 40 Mpc , enough to perform detailed time-evolved spectroscopy on several events each year .
This study took place in the framework of the DUAL mission proposal which was recently submitted to ESA for the third medium class mission of the Cosmic Vision program .