Conveners
Stars
- Gasper Kukec Mezek (Linnaeus University)
Fan-shaped jets can be observed above light bridges and are driven by reconnection of the vertical umbral field with the more horizontal field above the light bridges. Because these jets are not fully opaque in chromospheric lines, one cannot study their spectra without the highly complex considerations of radiative transfer in spectral lines from the atmosphere behind the fan.
We take...
We present a detailed study of the composition of 20 M giants in the Galactic center with 15 of them confirmed to be in the nuclear star cluster. As a control sample we have also observed 7 M giants in the Milky Way disk with similar stellar parameters. All 27 stars are observed using the NIRSPEC spectrograph on the KECK II telescope in the K-band at a resolving power of R=23,000. We report...
Stars on the asymptotic giant branch (AGB) lose a substantial part of their mass through stellar winds. Pulsations induce shock waves throughout the stellar atmosphere which compresses and elevates gas to cooler regions where dust can form. The newly formed dust particles are accelerated outwards by radiation pressure, dragging gas along, resulting in a wind. Dynamical atmosphere and wind...
M dwarfs have become an increasingly interesting target in the search for exoplanets. This is due to their small radii and low temperature which makes finding planets via both radial and transit methods easier. M dwarfs are however know to be tricky targets. The best option we have to characterise their atmospheres is using spectroscopy. This is not an easy task. M dwarf spectra are filled...
X-ray polarisation is set to open a new window into highly energetic astronomical sources like neutron stars and black holes. The upcoming launches of IXPE (a satellite-based soft X-ray polarimeter) in late 2021 and XL-Calibur (a balloon-borne hard X-ray polarimeter) in 2022 will soon provide sensitive X-ray polarisation measurements. These measurements can be used to study the strong magnetic...
Investigation of the magnetic fields on stars is important because they affect many different properties of stars at multiple stages of their evolution. The magnetic field is also a key component in the interaction between the star and its surroundings, possibly affecting habitability. The study of binaries offers a unique opportunity due to the fact that the formation of the components are...
