Recorded Colloquium at Harvard & Smithsonian Center for Astrophysics

27 Sep
Colloquium recording Sept 26, 2019, Harvard & Smithsonian Center for Astrophysics, Cambridge, MA.

From Birth to Chirp – Astrophysics of Massive Stars as Gravitational Wave Progenitors.

Abstract: How did they form?’ is a question many asked when LIGO announced the first direct detection of gravitational waves originating from two surprisingly heavy stellar-mass black holes. With masses of about 30 solar masses each, they outweighed all of the known black holes known from X-ray binaries. Now, four years after the first detection, alerts of new triggers come in at a rate of almost one per week. The analysis of the first eleven events has been published and we learned that the first system was not exceptional: the majority of detected events involve heavy black holes. In parallel, classical telescopes have been revolutionizing our understanding of the properties of young massive stars.

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Final Kiss of Two Stars Heading for Catastrophe (ESO press release)

21 Oct

 

Using ESO’s Very Large Telescope, an international team of astronomers have found the hottest and most massive double star with components so close that they touch each other. The two stars in the extreme system VFTS 352 could be heading for a dramatic end, during which the two stars either coalesce to create a single giant star, or form a binary black hole.

Almeida, Sana, de Mink et al. ApJ in press,  preprint

 

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