From Massive Stars to Supernova Remnants

It becomes more and more clear that supernovae do not explode in a spherically symmetric fashion. Small scale anisotropies are observed to occur in supernovae and supernova remnants, which must have their origin in local conditions of the exploding star, or in its circumstellar medium. Large scale anisotropies are also frequent, in the medium around the star before it explodes, in the supernova explosion itself, and in supernova remnants. The most extreme examples are provided by hypernovae and (long) gamma-ray bursts. Theoretically, these anisotropies are suspected to be connected with the supernova progenitor evolution, which shapes the internal constitution of the star before it explodes, but also its circumstellar surroundings.  Other possibilities to produce anisotropies include the collapse and the supernova explosion mechanism itself.

We are aiming at bringing together, for two weeks, the key experts in the fields of massive star evolution, circumstellar medium evolution, supernova explosions, supernova/GRB-circumstellar medium interaction, and early supernova remnant evolution, with the aim to advance our understanding of the various anisotropic processes involved. Our idea is that by combining the world expertise in the mentioned fields in one workshop, one may uncover critical physical connections across these fields. For example, the internal rotation of a massive star may lead to anisotropic stellar winds and circumstellar medium structures, but also decide whether the star produces a gamma-ray burst or just a supernova. All this will determine the explosion/circumstellar medium interaction and shape the supernova remnant. Our theoretical understanding of the processes involved, but also the observations of anisotropies around stars, in stellar explosions, and in supernova remnants have reached a stage which makes the time ripe for this approach.

We hope that the workshop will give rise to new ideas to understand the multitude of observed phenomena, to develop critical tests to new and existing ideas, and pave the road to future observational and theoretical studies as explorations of such ideas.

Supernovae of Type Ia, i.e. exploding white dwarfs in binary systems, are not in the focus of this workshop, but side line discussions on this topic are expected as well.