Related papers: Constraining white-dwarf kicks in globular cluster…
In dense stellar systems the frequent dynamical interactions between stars play a crucial role in the formation and evolution of compact binaries. We study these processes using a novel approach combining a state-of-the-art binary…
The evolution of star clusters is studied using N-body simulations in which the evolution of single stars and binaries are taken self-consistently into account. Initial conditions are chosen to represent relatively young Galactic open…
High-mass binaries hosting young pulsars can be powerful gamma-ray emitters. The stellar wind of the massive star in the system is expected to be clumpy. Since the high-energy emission comes from the pulsar-star wind interaction, the…
Dynamical friction (DF) may affect the dynamics of stars moving through dense media. This is the case for stars and compact objects (COs) crossing active galactic nuclei (AGN) discs, stellar clusters, and common envelopes (CE), driving…
We review the current state of our knowledge concerning the rotation and angular momentum evolution of young stellar objects and brown dwarfs from a primarily observational view point. Periods are typically accurate to 1% and available for…
In this paper we derive a bound on the rate of change of the gravitational constant G coming from the pulsating white dwarf G117-B15A. This star is a ZZ Ceti pulsator extensively studied with astroseismological techniques for last three…
Numerical and observational evidence suggests that massive white dwarfs dominate the innermost regions of core-collapsed globular clusters by both number and total mass. Using NGC 6397 as a test case, we constrain the features of white…
Globular clusters are collisional systems, meaning that the stars inside them interact on timescales much shorter than the age of the Universe. These frequent interactions transfer energy between stars and set up observable trends that tell…
Multiple star systems interact strongly with Galactic field stars when the outer semi-major axis of a triple or multiple star is > 10 3 AU. Stable triples composed of two white-dwarfs (WD) and a low mass main sequence (MS) star in a wide…
As stars evolve along the Asymptotic Giant Branch, strong winds are driven from the outer envelope. These winds form a shell, which may ultimately become a planetary nebula. Many planetary nebulae are highly asymmetric, hinting at the…
The rotation of horizontal branch stars places important constraints on angular momentum evolution in evolved stars and therefore rotational mixing on the giant branch. Prompted by new observations of rotation rates of horizontal branch…
Gravitational interactions in very young high-density stellar clusters can to some degree change the angular momentum in the circumstellar discs surrounding initially the majority of stars. However, for most stars the cluster environment…
The prediction of the spins of the compact remnants is a fundamental goal of the theory of stellar evolution. Here, we confront the predictions for white dwarf spins from evolutionary models including rotation with observational…
The presence of a strong magnetic field is a feature common to a significant fraction of degenerate stars, yet little is understood about field origin and evolution. New observational constraints from volume-limited surveys point to a more…
We present a model for the rotational evolution of a young, solar-mass star interacting magnetically with an accretion disk. As in a previous paper (Paper I), the model includes changes in the star's mass and radius as it descends the…
Fast line-driven stellar winds play an important role in the evolution of planetary nebulae. We provide global hot star wind models of central stars of planetary nebulae. The models predict wind structure including the mass-loss rates,…
Young and rapidly rotating stars are known for intense, dynamo generated magnetic fields. Spectropolarimetric observations of those stars in precisely aged clusters are key input for gyrochronology and magnetochronology. We use ZDI maps of…
Upon their formation, dynamically cool (collapsing) star clusters will, within only a few million years, achieve stellar mass segregation for stars down to a few solar masses, simply because of gravitational two-body encounters. Since…
A secular variation of $G$ modifies the structure and evolutionary time scales of white dwarfs. Using an state-of-the-art stellar evolutionary code, an up-to-date pulsational code, and a detailed population synthesis code we demonstrate…
We have investigated the relationship between the kinematics and mass of young (<3x10^8 years) white dwarfs using proper motions. Our sample is taken from the colour selected catalogues of SDSS (Eisenstein et al. 2006) and the Palomar-Green…