相关论文: Spin Alignment of Dark Matter Halos: Mad Halos
The standard cosmological paradigm currently lacks a detailed account of physics in the dark sector, the dark matter and energy that dominate cosmic evolution. In this paper, we consider the distinguishing factors between three alternative…
We use seven high-resolution $N$-body simulations to study the correlations among different halo properties (assembly time, spin, shape and substructure), and how these halo properties are correlated with the large-scale environment in…
We employ a semi-analytical methodology to estimate the dark matter halo spin of HI-rich galaxies in the Arecibo Legacy Fast Alfa Survey and investigate the relationship between halo spin and the proximity of galaxies to cosmic filaments.…
During the growth of a cold dark matter halo, the direction of its spin can undergo rapid changes. These could disrupt or even destroy a stellar disc forming in the halo, possibly resulting in the generation of a bulge or spheroid. We…
We extend the random-walk model of Vitvitska et al. for predicting the spins of dark matter halos from their merger histories. Using updated merger rates, orbital parameter distributions, and N-body constraints we show that this model can…
We investigate the magnitude and internal alignment of the angular momentum of cold dark matter haloes in simulations with and without baryons. We analyse the cumulative angular momentum profiles of hundreds of thousands of haloes in the…
We investigate statistically the dynamical consequences of cosmological fluxes of matter and related moments on progenitors of today's dark matter haloes. Their dynamics is described via canonical perturbation theory which accounts for two…
We present direct $N$-body simulations of tidally filling 30,000 ${\rm M}_\odot$ star clusters orbiting between 10 kpc and 100 kpc in galaxies with a range of dark matter substructure properties. The time-dependent tidal force is determined…
We investigate the alignment of haloes with the filaments of the cosmic web using an unprecedently large sample of dark matter haloes taken from the P-Millennium $\Lambda$CDM cosmological N-body simulation. We use the state-of-the-art NEXUS…
We use simulations of merging galaxies to explore the sensitivity of the morphology of tidal tails to variations of the halo mass distributions in the parent galaxies. Our goal is to constrain the mass of dark halos in well-known merging…
We present that the spin$-$orbit alignment (SOA; i.e., the angular alignment between the spin vector of a halo and the orbital angular momentum vector of its neighbor) provides an important clue to how galactic angular momenta develop. In…
We employ a stochastic approach to probing the origin of the log-normal distributions of halo spin in N-body simulations. After analyzing spin evolution in halo merging trees, it was found that a spin change can be characterized by a…
We study the effect of tidal torques on the collapse of density peaks through the equations of motion of a shell of barionic matter falling into the central regions of a cluster of galaxies. We calculate the time of collapse of the…
We test a particular theory of dark matter in which dark matter axions form ring "caustics" in the plane of the Milky Way against actual observations of Milky Way stars. According to this theory, cold, collisionless dark matter particles…
We describe a semi-analytic model to predict the triaxial shapes of dark matter halos utilizing the sequences of random merging events captured in merger trees to follow the evolution of each halo's energy tensor. When coupled with a simple…
We explore how the galaxy stellar spins acquire a peculiar tendency of being aligned with the major principal axes of the local tidal fields, in contrast to their DM counterparts which tend to be perpendicular to them, regardless of their…
We have analyzed galaxy and group-sized dark matter halos formed in a high resolution LCDM numerical N-body simulation in order to study the rotation of the triaxial figure, a property in principle independent of the angular momentum of the…
Tidal interactions between neighboring objects span across the whole admissible range of lengths in nature: from, say, atoms to clusters of galaxies i.e. from micro to macrocosms. According to current cosmological theories, galaxies are…
Dark matter haloes in cosmological filaments and walls have their spin vector aligned (in average) with their host structure. While haloes in walls are aligned with the plane of the wall independently of their mass, haloes in filaments…
We study the empirical relation between an astronomical object's angular momentum $J$ and mass $M$, $J=\beta M^\alpha$, the $J-M$ relation, using N-body simulations. In particular, we investigate the time evolution of the $J-M$ relation to…