Related papers: Magnetic activity in close binary systems
There are obvious and direct ways in which the presence of binary companions may affect activity in OB stars through tidal interactions. In this review, however, I consider a more fundamental role for multiplicity and explore claims that…
The existence of starspots on late-type giant stars in close binary systems, that exhibit rapid rotation due to tidal locking, has been known for more than five decades. Photometric monitoring spanning decades has allowed studying the…
We apply a model of dynamo-driven mass loss, magnetic braking and tidal friction to the evolution of stars with cool convective envelopes; in particular we apply it to binary stars where the combination of magnetic braking and tidal…
We present an overview of pulsating stars in close binaries, focusing on the question what role the dupliticity plays in triggering and/or modifying stellar oscillations and on how it can help us to interpret the oscillatory behaviour of…
Massive stars with solar metallicity lose important amounts of rotational angular momentum through their winds. When a magnetic field is present at the surface of a star, efficient angular momentum losses can still be achieved even when the…
By numerically solving the equations of rotating magnetohydrodynamics (MHD), the magnetic effect on dynamical tide is studied. It is found that magnetic field has a significant impact not only on the flow structure, i.e. the internal shear…
The LISA mission will observe gravitational waves emitted from tens of thousands of galactic binaries, in particular white dwarf binary systems. These objects are known to have intense magnetic fields. However, these fields are usually not…
The magnetic field of a host star can impact the orbit of a stellar partner, planet, or asteroid if the orbiting body is itself magnetic or electrically conducting. Here, we focus on the instantaneous magnetic forces on an orbiting body in…
We discuss the potential role that tidal flows in asynchronous binary stars may play in transporting chemically enriched material from deep layers towards the surface and the corresponding observational consequences of these processes. We…
Tidal interactions influence the orbital motions of binary star systems and extrasolar planets alike. Tides also affect stellar and planetary rotation rates. We demonstrate that in addition to altering spin synchronization and…
We analise the behavior of lithium abundance as a function of effective temperature, projected rotational velocity, orbital period and eccentricity for a sample of 68 binary systems with giant component and orbital period ranging from about…
Previous studies have found that red giants (RGs) in close binary systems undergoing spin-orbit resonance exhibit an enhanced level of magnetic activity with respect to single RGs rotating at the same rate, from measurements of photometric…
The effects of binary tidal forces on transport within an accretion disk are studied with a time-dependent hydrodynamical model of a two-dimensional isothermal accretion disk. Tidal forces quickly truncate the accretion disk to radii of…
Stars and gaseous planets are magnetised objects but the influence of magnetic fields on their tidal responses and dissipation rates has not been well explored. We present the first exploratory nonlinear magnetohydrodynamic (MHD)…
Tidal dissipation in stars is one of the key physical mechanisms that drive the evolution of binary and multiple stars. As in the Earth oceans, it corresponds to the resonant excitation of their eigenmodes of oscillation and their damping.…
Magnetic helicity effects are discussed in laboratory and astrophysical settings. First, dynamo action in Taylor-Green flows is discussed for different boundary conditions. However, because of the lack of scale separation with respect to…
Dynamo action owing to helically forced turbulence and large-scale shear is studied using direct numerical simulations. The resulting magnetic field displays propagating wave-like behavior. This behavior can be modelled in terms of an…
The validity of the classical formula for the rate of secular apsidal motion in close binaries is investigated for a sequence of models of a 5 solar mass star ranging from the last stages of the C12 -> N14 reaction to the phase where…
The theory of large scale dynamos is reviewed with particular emphasis on the magnetic helicity constraint in the presence of closed and open boundaries. In the presence of closed or periodic boundaries, helical dynamos respond to the…
A star on a nearly radial trajectory approaching a massive black hole (MBH) gets tidally disrupted if it comes sufficiently close to the MBH. Here we explore what happens to binary stars whose centers of mass approach the MBH on nearly…