相关论文: A Pluto-Charon Sonata III. Growth of Charon from a…

We present a systematic study of the evolution of intermediate- and low-mass X-ray binaries consisting of an accreting neutron star of mass $1.0-1.8 M_{\odot}$ and a donor star of mass $1.0-6.0 M_{\odot}$. In our calculations we take into…

Using Chandra ACIS-S, we have obtained imaging Xray spectrophotometry of the Pluto system in support of the New Horizons flyby on 14 July 2015. 174 ksec of observations were obtained on 4 visits in Feb 2014 to Aug 2015. We measured a net…

We investigate the orbital evolution of particles in a planet's chaotic zone to determine their final destinations and their timescales of clearing. There are four possible final states of chaotic particles: collision with the planet,…

We have investigated i) the formation of gravitationally bounded pairs of gas-giant planets (which we call "binary planets") from capturing each other through planet-planet dynamical tide during their close encounters and ii) the following…

We present the results of hydrodynamic simulations of the formation and subsequent orbital evolution of giant planets embedded in a circumbinary disc. We assume that a 20 earth masses core has migrated to the edge of the inner cavity formed…

The terrestrial planets formed by accretion of asteroid-like objects within the inner solar system's protoplanetary disk. Previous works have found that forming a small-mass Mars requires the disk to contain little mass beyond ~1.5 au…

The spacings of super-Earths in multi-transiting systems exhibit a distribution that is broad and mostly featureless, with the exception of notable excesses of planet pairs situated a few percent wide of first-order mean motion resonances…

Intermediate-scale spurs are common in spiral galaxies, but perhaps most distinctively evident in a recent HST image of M51 (Scoville & Rector 2001). We investigate, using time-dependent numerical MHD simulations, how such spurs could form…

Recent observations point to the presence of structured dust grains in the discs surrounding young brown dwarfs, thus implying that the first stages of planet formation take place also in the sub-stellar regime. Here, we investigate the…

We suggest that low-mass hydrogen-burning stars like the Sun should sometimes form with massive extended discs; and we show, by means of radiation hydrodynamic simulations, that the outer parts of such discs (R>100 AU) are likely to…

The New Horizons mission to the Kuiper Belt has recently revealed intriguing features on the surface of Charon, including a network of chasmata, cutting across or around a series of high topography features, conjoining to form a belt. It is…

We examine characteristics of circumbinary orbits in the context of current planet formation scenarios. Analytical perturbation theory predicts the existence of nested circumbinary orbits that are generalizations of circular paths around a…

Binaries occur in many astrophysical systems, from young protostellar binaries in star forming regions to supermassive black hole binaries in galaxy centers. In many cases, a circumbinary disk of gas forms around the binary with an orbit…

We investigate the interaction between an eccentric planet and a less massive external debris disc. This scenario could occur after planet-planet scattering or merging events. We characterise the evolution over a wide range of initial…

Gravitational and electronic forces produce a correlation between the mass and shape of objects in the universe. For example, at an average radius of ~ 200 km - 300 km, the icy moons and rocky asteroids of our Solar System transition from a…

Exoplanetary systems are found not only among single stars, but also binaries of widely varying parameters. Binaries with separations of 100--1000 au are prevalent in the Solar neighborhood; at these separations planet formation around a…

It has been proposed recently that the first step in the formation of both rocky and gas giant planets is dust sedimentation into a solid core inside a gas clump (giant planet embryo). The clumps are then assumed to migrate closer to the…

Recent observations have unveiled a population of pulsars with spin periods of a few minutes to hours that lie beyond the traditional ``death line.'' If they originate from neutron stars (NSs), the existence of such ultra-long period…

Although discs of dust and gas have been observed orbiting white dwarfs, the origin of this circumstellar matter is uncertain. We hypothesize that the in-situ breakup of small bodies such as asteroids spun to fission during the giant branch…

We present the results of a systematic study of the formation and evolution of binaries containing black holes and normal-star companions with a wide range of masses. We first reexamine the standard formation scenario for close black-hole…