[Astronomy seminar] Astro department seminar - Friday, Sept 16th - Avishai Gilkis

[Astronomy seminar announcements]

The next SU astronomy departmental seminar will take place on Friday September 16th at 10:30 in room FC 61 (AlbaNova building, 6th floor) and on zoom.

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Speaker: Avishai Gilkis - Tel Aviv University
Title: Uncertainty in envelope removal of core-collapse supernova progenitors

Abstract: 
The theoretical modeling of massive star evolution is riddled with uncertainties. Two such unresolved aspects are mass loss by stellar winds and mixing in stellar interiors. In my talk I will discuss the implications of these uncertainties on reconciling theory with observations of massive stellar endpoints. In the first part I will present the role of winds for progenitors of stripped-envelope supernovae. While it is commonly assumed that binary interaction removes the hydrogen envelope, the assumed post-interaction mass-loss rate is crucial for the resulting supernova type. I will show how we assess the hydrogen mass in stripped-envelope supernova progenitors by comparing pre-supernova photometry with evolution models. In the second part of the talk I will focus on the lack of observed cool and very luminous supergiant stars, an unexplained phenomenon termed the “Humphreys-Davidson Limit”, which is in contrast to simulations of evolved massive stars. I will show how enhanced mixing above convective cores can aid in removing the hydrogen envelope and ease the tension between theory and observations for such stars at the high-mass end, which are also thought to be the progenitors of merging black holes.

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We look forward to seeing many of you there. Thanks!

Eliot and Kris


Topic: Astronomy Department Seminar Gregor Traven
Time: Sept 9, 2022 10:30 AM Stockholm

Join Zoom Meeting:
https://stockholmuniversity.zoom.us/s/61002076352

Meeting ID: 610 0207 6352
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