Related papers: The structure and evolution of a high-mass stellar…
The exact evolution of elements in the universe, from primordial to heavier elements produced via the r-process, is still under scrutiny. The supernova deaths of the very first stars led to the enrichment of their local environments, and…
Neutron star mergers have been proposed as the main source of heavy $r$-process nucleosynthesis in the Universe. However, the mergers' significant expected delay after binary formation is in tension with observed very early $r$-process…
Blue supergiants are the brightest stars in their host galaxies and yet their evolutionary status has been a long-standing problem in stellar astrophysics. In this pioneering work, we present a large sample of 59 early B-type supergiants in…
Three-dimensional simulations usually fail to cover the entire dynamical common-envelope phase of gravitational wave progenitor systems due to the vast range of spatial and temporal scales involved. We investigated the common-envelope…
The study of massive binary systems has steadily progressed over the past decades, with increasing focus on their evolution, interactions and mergers, driven by improvements in computational modelling and observational techniques. In…
The evolution of massive stars is affected by a variety of physical processes including convection, rotation, mass loss and binary interaction. Because these processes modify the internal chemical abundance profiles in multiple ways…
More than half of all main-sequence (MS) stars have one or more companions, and many of those with initial masses <8 M$_\odot$ are born in hierarchical triples. These systems feature two stars in a close orbit (the inner binary) while a…
Stars spend most of their lifetime on the main sequence (MS), where hydrogen burning establishes the internal chemical structure that governs the subsequent evolution. In massive stars, mass loss through winds and binary interactions can…
When two stars collide and merge they form a new star that can stand out against the background population in a starcluster as a blue straggler. In so called collision runaways many stars can merge and may form a very massive star that…
The structure of stellar envelopes strongly influences the course and outcome of binary mass transfer, in particular of common envelope (CE) evolution. Convective envelopes can most easily be ejected during CE events, leading to…
The majority of massive stars live in binary or multiple systems and will interact during their lifetimes, which helps to explain the observed diversity of core-collapse supernovae. Donor stars in binary systems can lose most of their…
We investigate the long-term evolution and observability of remnants originating from the merger of compact binary systems and discuss the differences to supernova remnants. Compact binary mergers expel much smaller amounts of mass at much…
Over forty years of research suggests that the common envelope phase, in which an evolved star engulfs its companion upon expansion, is the critical evolutionary stage forming short-period, compact-object binary systems, such as coalescing…
Two neutron stars merge somewhere in the Universe approximately every 10 seconds, creating violent explosions observable in gravitational waves and across the electromagnetic spectrum. The transformative coincident gravitational-wave and…
Massive stars can develop into tepid supergiants at several stages of their post main-sequence evolution, prior to core He-burning, on a blue loop, or close to the final supernova explosion. We discuss observational constraints on models of…
A significant fraction of stars experience close interactions, including collisions resulting from gravitational encounters and mergers within close binary systems. These processes can produce more massive stars that may give rise to…
Rotation can have severe consequences for the evolution of massive stars. It is now considered as one of the main parameters, alongside mass and metallicity that determine the final fate of single stars. In massive, fast rotating stars…
We suggest that the vigorous core convection during core helium flash on the tip of the red giant branch (RGB) of low mass stars excites waves that carry energy to the envelope and inflate it for few years to increase the number of extreme…
(abbreviated) The evolution of intermediate mass stars at very low metallicity during their final thermal pulse asymptotic giant branch phase is studied in detail. As representative examples models with initial masses of 4Msun and 5Msun…
Most galaxies have central massive black holes (BH), and merge with others during their evolution, as strongly suggested by recent observations. Consequently a black hole binary (BHB) emerges. Considering the evolution of the binary when it…