Related papers: Probabilistic eccentricity bifurcation for stars a…
Many exoplanets in close-in orbits are observed to have relatively high eccentricities and large stellar obliquities. We explore the possibility that these result from planet-planet scattering by studying the dynamical outcomes from a large…
The orbits of stars close to a massive black hole are nearly Keplerian ellipses. Such orbits exert long term torques on each other, which lead to an enhanced angular momentum relaxation known as resonant relaxation. Under certain…
Compact object binaries formed from dynamics interactions will generically have non-zero orbital eccentricity. The gravitational waves from such binaries can change drastically depending on how large the eccentricity is, ranging from…
Discs in binaries have a complex behavior because of the perturbations of the companion star. Planet formation in binary-star systems both depend on the companion star parameters and on the properties of the circumstellar disc. An eccentric…
Recent discoveries of strongly misaligned transiting exoplanets pose a challenge to the established planet formation theory which assumes planetary systems to form and evolve in isolation. However, the fact that the majority of stars…
Instabilities and strong dynamical interactions between multiple giant planets have been proposed as a possible explanation for the surprising orbital properties of extrasolar planetary systems. In particular, dynamical instabilities seem…
An important issue in the dynamics of neutron star binaries is whether tidal interaction can cause the individual stars to collapse into black holes during inspiral. To understand this issue better, we study the dynamics of a cluster of…
Some of the mass that feeds the growth of a massive black hole (BH) in a galactic center is supplied by tidal disruption of stars that approach it on unbound, low angular momentum orbits. For each star that is disrupted, others narrowly…
We investigate observations of circumbinary disks (CBD), to find evidence for an equilibrium eccentricity predicted by current binary accretion theory. Although stellar binary demographics in the Milky Way show no evidence for a preferred…
The eccentricity distribution of exoplanets is known from radial velocity surveys to be divergent from circular orbits beyond 0.1 AU. This is particularly the case for large planets where the radial velocity technique is most sensitive. The…
We study the probability of close encounters between stars from a nuclear cluster and a massive black hole. The gravitational field of the system is dominated by the black hole in its sphere of influence. It is further modified by the…
We explore the hardening of a massive black hole binary embedded in a circum-binary gas disc when the binary and the gas are coplanar and the gas is counter-rotating. The secondary black hole, revolving in the direction opposite to the gas,…
Improved observations of globular clusters are uncovering a large number of radio pulsars and of X-ray sources. The latter include binaries in which a neutron star or a white dwarf accretes matter from a companion, recycled pulsars, and…
A possibility of pregalactic seeds of the Active Galactic Nuclei can be a nontrivial cosmological consequence of particle theory. Such seeds can appear as Primordial Black Hole (PBH) clusters, formed in the succession of phase transitions…
Binaries of supermassive black holes (MBHBs) represent the primary sources of the gravitational wave background (GWB) detectable by Pulsar Timing Arrays (PTAs). The eccentricity with which binaries form in galactic mergers is the key…
It is strongly believed that Andromeda's double nucleus signals a disk of stars revolving around its central super-massive black hole on eccentric Keplerian orbits with nearly aligned apsides. A self-consistent stellar dynamical origin for…
Aims: Our goal is to investigate how the strength of episodic accretion bursts depends on eccentricity. Methods: We investigate the binary trigger hypothesis in longer-period (>20yr) binaries by carrying out three-dimensional…
Physical collisions and close approaches between stars play an important role in the formation of exotic stellar systems. Standard theories suggest that collisions are rare, occurring only via random encounters between stars in dense…
The eccentricity evolution of multiple planet systems can provide valuable constraints on planet formation models. Unfortunately, the inevitable uncertainties in the current orbital elements can lead to significant ambiguities in the nature…
The basic properties of the candidate binary cluster population in the Magellanic Clouds and Galaxy are similar. The fraction of candidate binary systems is $\sim$10% and the pair separation histogram exhibits a bimodal distribution…