We study the motion of gas clouds in vicinity boson stars, performing simulations with black hole accretion code. compare particle along geodesics and analyze tidal effects on clouds, which leads to disruption clouds. First we consider small dense associated three different types bound orbits close star mechanisms debris formation for these. infer from that lifetimes these nearby are longer ini...

We classify orbits of stars that are bound to central black holes in galactic nuclei. The stars move under the combined gravitational influences of the black hole and the central star cluster. Within the sphere of influence of the black hole, the orbital periods of the stars are much shorter than the periods of precession. We average over the orbital motion and end up with a simpler problem and...

The Kozai mechanism often destabilises high inclination orbits. It couples changes in the eccentricity and inclination, and drives high inclination, circular orbits to low inclination, eccentric orbits. In a recent study of the dynamics of planetesimals in the quadruple star system HD98800 (Verrier & Evans 2008), there were significant numbers of stable particles in circumbinary polar orbits ab...

To date, studies of $\textit{Laplace Surface}$ dynamics have concerned themselves with test particle orbits fixed shape and orientation in the combined field an oblate central body (to which is bound) a distant, inclined, companion captured to quadrupolar order. While amply sufficient for satellites around planets on near-circular orbits, approximation fails capture essential dynamical features...

ABSTRACT The nucleus of our nearest, large galactic neighbour, M31, contains an eccentric nuclear disc – a stars on eccentric, apsidally aligned orbits around supermassive black hole (SMBH). Previous studies discs considered only isolated disc, and did not study their dynamics under galaxy mergers (particularly perturbing SMBH). Here, we present the first how are affected by merger. We perform ...

We re-analyze the precision radial velocity (RV) observations of HD160691 (μ Ara) by the Anglo-Australian Planet Search Team. The star is supposed to host two Jovian companions (HD160691b, HD160691c) in longperiod orbits (∼ 630 days and ∼ 2500 days, respectively) and a hot-Neptune (HD160691d) in ∼ 9 days orbit. We perform a global search for the best fits in the orbital parameters space with a ...

We re-analyze the precision radial velocity (RV) observations of HD160691 (μ Ara) by the Anglo-Australian Planet Search Team. The star is supposed to host two Jovian companions (HD160691b, HD160691c) in longperiod orbits (∼ 630 days and ∼ 2500 days, respectively) and a hot-Neptune (HD160691d) in ∼ 9 days orbit. We perform a global search for the best fits in the orbital parameters space with a ...

We present stellar dynamical models of the lopsided, double–peaked nucleus of M31, derived from Hubble Space Telescope (HST) photometry. A Schwarzschild–type method, in conjunction with Richardson–Lucy deconvolution, was employed to construct steadily rotating, hot, stellar disks. The stars orbit a massive dark object, on prograde and retrograde quasi–periodic loop orbits. Our results support T...

Recent discovery of kilohertz quasi-periodic brightness oscillations of low mass X-ray binaries (LMXBs) has attracted attention to highly relativistic periodic motion near accreting neutron stars. Most models proposed so far involve (almost) inertial motion in the vicinity of the stars’ innermost stable circular orbits. In the present paper we study general-relativistic circular and eccentric o...