相关论文: Dark Matter as a Trigger for Periodic Comet Impact…
We model vertical breathing mode perturbations in the Milky Way's stellar disc and study their effects on estimates of the local dark matter density, surface density, and vertical force. Evidence for these perturbations, which involve…
The formation and growth of black holes can strongly influence the distribution of dark matter around them. I discuss here the different types of dark matter overdensities around black holes, including dark matter cusps, spikes, mounds,…
Metallic bodies that were the cores of differentiated bodies are sources of iron meteorites and are considered to have formed early in the terrestrial planet region before migrating to the main asteroid belt. Surface temperatures and mutual…
The cold dark matter model successfully explains both the emergence and evolution of cosmic structures on large scales and, when we include a cosmological constant, the properties of the homogeneous and isotropic Universe. However, the cold…
We study the evolution of long-period comets by numerical integration of their orbits, following comets from their origin in the Oort cloud until their final escape or destruction, in a model solar system consisting of the Sun, the four…
Structures observed in debris disks may be caused by gravitational interaction with planetary or stellar companions. These perturbed disks are often thought to indicate the presence of planets and offer insights into the properties of both…
The formation and evolution of a circumstellar disk in magnetized cloud cores is investigated from prestellar core stage until sim 10^4 yr after protostar formation. In the circumstellar disk, fragmentation first occurs due to gravitational…
Using the cometary nucleus model developed by Espinasse et al. (1991), we calculate the thermodynamical evolution of Comet 9P/Tempel 1 over a period of 360 years. Starting from an initially amorphous cometary nucleus which incorporates an…
Galactic rotation curves are often considered the first robust evidence for the existence of dark matter. However, even in the presence of a dark matter halo, other galactic-scale observations, such as the Baryonic Tully-Fisher Relation and…
Although highly successful on cosmological scales, Cold Dark Matter (CDM) models predict unobserved over-dense `cusps' in dwarf galaxies and overestimate their formation rate. We consider an ultra-light axion-like scalar boson which…
We propose a comprehensive theory of dark matter that explains the recent proliferation of unexpected observations in high-energy astrophysics. Cosmic ray spectra from ATIC and PAMELA require a WIMP with mass M_chi ~ 500 - 800 GeV that…
We present various instability mechanisms in the accreting black hole systems which might indicate at the connection between the accretion disk and jet. The jets observed in microquasars can have a persistent or blobby morphology.…
Direct detection of dark matter continues to elude scientists' many attempts to see it interact, and still to this day the only way we know it is there is through observed gravitational effects. The many search experiments are at the point…
As a binary pulsar moves through a wind of dark matter particles, the resulting dynamical friction modifies the binary's orbit. We study this effect for the double disk dark matter (DDDM) scenario, where a fraction of the dark matter is…
The tidal disruption of stars by (super-)massive black holes in galactic nuclei has been discussed in theoretical terms for about 30 years but only in the past decade have we been able to detect such events in substantial numbers. Thus, we…
The recent discovery of three interstellar comets in the solar system indicates the presence of so-far unaccounted baryonic matter in the Galaxy as a population of inter-stellar objects (ISO). The contribution of ISOs to the overall mass…
High levels of dust have been detected in the immediate vicinity of many stars, both young and old. A promising scenario to explain the presence of this short-lived dust is that these analogues to the Zodiacal cloud (or exozodis) are…
Dark matter or modifications of the Newtonian inverse-square law in the solar-system are studied with accurate planetary astrometric data. From extra-perihelion precession and possible changes in the third Kepler's law, we get an upper…
The variability of accretion rate, which is believed to induce the aperiodic variability of X-ray emission from disk, may affect the energy injection into the jet. In this spirit, a correlation between disk emission and jet emission can be…
Impacts by rocky and icy bodies are thought to have played a key role in shaping the composition of solar system objects, including the Earth's habitability. Hence, it is likely that they play a similar role in exoplanetary systems. We…