Driving asymmetric red supergiants winds with binary interactions

New paper by PhD student Camille Landri looks at how we can get asymmetric outflows from red supergiants such as VY CMa and other similar objects. The idea is that a companion coming in on a grazing excentric orbit will unbind a small amount of gas from the red supergiant. This gas is subject to rapid radiative cooling and forms dust, which gets pushed away from the supergiant by its radiative pressure. Radiative cooling and dust driving are necessary to form outflows that are anisotropic in the sense that the ejection happens only in a fraction of a solid angle near the pericenter. After many grazing orbits, the ejections form an asymmetric structure with imprinted spiral-like pattern. The paper (accepted to MNRAS) discusses origin, final fate, and observational implications of this scenario.

Two student grants for our group

Our PhD students were successful in obtaining student grants from the Grant Agency of the Charles University. Camille Landri (with Anthony Kirilov as a co-I) won with a project title The impact of binary evolution on common envelope evolution, and Jakub Cehula will work on Baryon ejection in magnetar giant flares: implications for r-process nucleosynthesis and fast radio bursts. Congratulations!

Computing time at IT4I

We were again successful in the competition for time on national supercomputer IT4Innovations. PhD student Camille Landri won 20 000 node hours (4.32 million CPU hours) on Barbora cluster and postdoc Damien Gagnier secured 82 000 node hours (10.496 million CPU hours) on Karolina cluster. Both awards are intended for projects involving binary star interactions and common envelope evolution.