出版社:SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要: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 56Ni, a radioactive element massively produced during SNe Ia events. Spectroscopy and light curvemeasurements of this gamma-ray line allow for a directmeasurement 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-s sensitivity of 1.8×10−6 ph/s/cm2 in the 3%-broadened line at 847 keV (in 1 Ms observation time), dozens of SNe Ia could be detected per year out to ∼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.