Related papers: Can Planets Influence the Horizontal Branch Morpho…
Planets are observed to orbit the component star(s) of stellar binary systems on so-called circumprimary or circumsecondary orbits, as well as around the entire binary system on so-called circumbinary orbits. Depending on the orbital…
We explore the dynamical evolution of a planet embedded in a disk surrounding a star part of a binary system where the orbital plane of the binary is significantly tilted respect to the initial disk plane. Our aim is to test whether the…
Planet searches around evolved giant stars are bringing new insights to planet formation theories by virtue of the broader stellar mass range of the host stars compared to the solar-type stars that have been the subject of most current…
Accretion of planetary material onto host stars may occur throughout a star's life. Especially prone to accretion, extrasolar planets in short-period orbits, while relatively rare, constitute a significant fraction of the known population,…
Revealing the mechanisms shaping the architecture of planetary systems is crucial for our understanding of their formation and evolution. In this context, it has been recently proposed that stellar clustering might be the key in shaping the…
The increased incidence of morphologically peculiar galaxies at faint magnitudes in the optical could be attributable either to "morphological k-corrections" (the change in appearance when viewing high-z objects at shorter rest-frame…
The evolution of a binary star system by various analytic approximations of mass transfer is discussed, with particular attention payed to the stability of these processes against runaway on the thermal and dynamical timescales of the mass…
Planetary systems can evolve dynamically even after the planets themselves have fully formed, and there is circumstantial evidence that most planetary systems become unstable after the disappearance of the gaseous protoplanetary disk.…
The discovery of over 50 planets around evolved stars and more than 35 debris discs orbiting white dwarfs highlight the increasing need to understand small body evolution around both early and asymptotic giant branch (GB) stars. Pebbles and…
As part of the search for planets around evolved stars, we can understand planet populations around significantly higher-mass stars than the Sun on the main sequence. This population is difficult to study any other way, particularly with…
Evidence of magnetic interaction between late-type stars and close-in giant planets is provided by the observations of stellar hot spots rotating synchronously with the planets and showing an enhancement of chromospheric and X-ray fluxes.…
Massive stars play a major role in the evolution of their host galaxies, and serve as important probes of the distant Universe. It has been established that the majority of massive stars reside in close binaries and will interact with their…
Recent observational constraints restrict the strict applicability of stellar dynamics in spirals to a few rotation periods. However, stellar dynamics concepts such as periodic orbits are invaluable for understanding the various dynamical…
We study the long-term orbital evolution of stars around a merging massive or supermassive black-hole (BH) binary, taking into account the general relativistic effect induced by the BH spin. When the BH spin is significant compared to and…
Mass loss and axial rotation are playing key roles in shaping the evolution of massive stars. They affect the tracks in the HR diagram, the lifetimes, the surface abundances, the hardness of the radiation field, the chemical yields, the…
I calculate the classical effects induced by an isotropic mass loss of a body on the orbital motion of a test particle around it. By applying my results to the phase in which the radius of the Sun, already moved to the Red Giant Branch of…
A significant fraction of the envelope of low- and intermediate-mass stars is unstable to convection, leading to sub-surface turbulent motion. Here, we consider and include the effects of turbulence pressure in our stellar evolution…
Beyond the main sequence solar type stars undergo extensive mass loss, providing an environment where planet and brown dwarf companions interact with the surrounding material. To examine the interaction of substellar mass objects embedded…
Rotation and mass loss are crucially interlinked properties of massive stars, strongly affecting their evolution and ultimate fate. Massive stars rotating near their breakup limit shed mass centrifugally, creating Be stars with…
The horizontal branch (HB) morphology of globular clusters (GCs) is mainly described by metallicity. The fact that some clusters with almost the same metallicity exhibit different HB demonstrates that other parameters are at work. We…