Gamma-Ray Observations of Supernovae

Using the gamma-rays from nucleosynthesis ejecta, supernovae can be ‘X-rayed’ into their deepest interiors. Days after the initial explosion of type Ia supernovae, the decay chain of 56Ni measured as a function of time can distinguish progenitor models. Several years after the explosion, the remnants of probably all supernovae are dominantly heated by the decay positrons of 44Ti. Over millennia, cosmic rays are accelerated in the remnants, thereby exciting the ejected material nuclearly, resulting in a probe for low-energy cosmic rays. Several Myrs later, the ejecta, especially from massive stars, now mixing with the interstellar medium, can be traced by the decay gamma-rays of 26Al and 60Fe.

In this talk, I will give an overview of gamma-ray measurements from exploding stars, starting from massive star wind phases, over explosive nucleosynthesis, towards feedback into the interstellar medium. The stellar evolution models, progenitor scenarios, and low-energy cosmic-rays will be discussed in the context of current (INTEGRAL) and future (COSI) instruments.