Galaxy Formation and Evolution - IAP Research Group

Date

Subject

Presented by

13 december 2012

The evolution of massive stars towards their death: rotation, binarity and mergers

Although they are rare and short-lived, massive stars play a major role in Universe. With their large luminosities, strong stellar winds and spectacular explosions they act as cosmic engines, heating and enriching their surroundings, where the next generation of stars and their planets are forming. I will discuss developments in the massive star community that led to new insight related to (1) the effects of stellar rotation and (2) the importance of binarity and (3) how these effects interplay.

In particular, I will discuss efforts to test rotating stellar models using the ongoing VLT-Flames Tarantula Survey and recent results that show that the preference for very close binary system is even stronger than initially thought. These findings imply that the majority (70%) of massive stars will interact with a companion before they explode at the end of their live.

The effects of rotation and binarity can drastically change the properties of both stars (brightness, color, ionizing flux, chemical yields, X-rays etc.) as well as their final fate as core-collapse and pair-instability supernovae and gamma-ray bursts. Since these effects are not accounted for in the widely used classic stellar models, the consequences for stellar populations and their feedback - nearby and at high redshift - still remain largely unexplored.

Selma E. de Mink
Space Telescope Science Institute, Johns Hopkins University, Baltimore, USA

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