1140011

The explosion mechanism associated with thermonuclear supernovae (SNIa) is still a matter of debate. However there is a wide agreement that high amounts of radioactive nuclei are produced during these events and they are expected to be strong gamma-ray emitters able to be used as diagnostic tools of the explosion. Detailed numerical simulations have convincingly shown that SPI and IBIS can be succesfully used to discriminate among the explosion mechanisms provided the supernova occurs at an appropriate distance. These tests include the temporal evolution of the lines as well as the value of the relative intensities the properties of the continuum and the linewidths. The data collected by the X-ray and optical monitors (JEM-X and OMC) will also be analysed as they can provide additional information about the nature of the presupernova system and the spatial heterogeneities of the ejecta. [truncated! Please see actual data for full text]