Hard X‐Rays and Gamma Rays from Type Ia Supernovae

The gamma-ray light curves and spectra are presented for a set of theoreticalType Ia supernova models including deflagration, detonation, delayeddetonation, and pulsating delayed detonations of Chandrasekhar mass whitedwarfs as well as merger scenarios that may involve more than the Chandrasekharmass and helium detonations of sub-Chandrasekhar mass white dwarfs. The resultshave been obtained with a Monte Carlo radiation transport scheme which takesinto account all relevant gamma-transitions and interaction processes. Theresult is a set of accurate line profiles which are characteristic of theinitial Ni-mass distribution of the supernova models. The gamma-rays probe theisotopic rather than just the elemental distribution of the radioactiveelements in the ejecta. Details of the line profiles including the line width,shift with respect to the rest frame, and line ratios are discussed. Withsufficient energy and temporal resolution, different model scenarios canclearly be distinguished. Observational strategies are discussed for currentand immediately upcoming generations of satellites (CGRO and INTEGRAL) as wellas projected future missions including concepts such as Laue telescopes. WithCGRO, it is currently possible with sufficiently early observations (nearoptical maximum) to distinguish helium detonations from explosions ofChandrasekhar mass progenitors and of those involving mergers up to a distanceof about 15 Mpc. This translates into one target of opportunity every eightyears. SNe Ia up to about 10 Mpc would allow detailed CGRO studies of lineratios of Co lines.Comment: 32 pages, Tex, ApJ, in pres