相关论文: Tilted Dark Halos are Common, Long-Lived, and can …

The outer disk of the Milky Way Galaxy is warped and flared. Several mechanisms have been proposed to explain these phenomena, but none have quantitatively reproduced both features. Recent work has demonstrated that the Galactic stellar…

Dark matter (DM) halos in $\Lambda$ Cold DM cosmological simulations are triaxial. Most exhibit figure rotation. We study 40 isolated halos with stellar disks from the TNG50 simulation suite across $\sim 4$~Gyr to understand whether and how…

The normal mode theory for warping of galaxy disks, in which disks are assumed to be tilted with respect to the equator of a massive, flattened dark halo, assumes a rigid, fixed halo. However, consideration of the back-reaction by a…

The dark matter halos in $\Lambda$CDM cosmological simulations are triaxial and highly flattened. In many cases, these triaxial equilibria are also tumbling slowly, typically about their short axes, with periods of order a Hubble time.…

When a galaxy forms, the disk may initially be tilted with respect to a flattened dark halo. The misalignment between the disk and the halo is a common explanation for galactic disk warps, since in this state, disks have precessing bending…

A galaxy disk embedded in a rotating halo experiences a dynamical friction force which causes it to warp when the angular momentum axes of the disk and halo are misaligned. Our fully self-consistent simulations of this process induce…

Large-scale warps in the outer parts of spiral galaxy discs have been observed for almost forty years, but their origin remains obscure. We review the dynamics of warped galaxy discs. We identify several mechanisms that could excite warps,…

A galactic disk in a spiral galaxy is generally believed to be embedded in an extended dark matter halo, which dominates its dynamics in the outer parts. However, the shape of the halo is not clearly understood. Here we show that the dark…

We investigate the tilting and warping of galactic disks in response to tidal torquing. The strength of the torque is determined from cosmological N-body simulations. We find the tidal torques to be dominated by substructure in the galactic…

We study the evolution of disk galaxies within the frame of the cold dark matter (CDM) cosmologies. The hydrodynamics of a centrifugally supported gaseous disk and the growth of a stellar disk are calculated in detail taking into account…

A standard paradigm is now available for the recent evolution (z < 10) of structure on galactic and larger scales. Most of the matter is assumed to be dark and dissipationless and to cluster hierarchically from gaussian initial conditions.…

The shape of the dark matter (DM) halo is key to understanding the hierarchical formation of the Galaxy. Despite extensive efforts in recent decades, however, its shape remains a matter of debate, with suggestions ranging from strongly…

Galaxies can form in a sufficiently deep gravitational potential so that efficient gas cooling occurs. We estimate that such potential is provided by a halo of mass $M \gtsim M_{c} \approx 7.0 \times 10^{12} ~ (\Delta_{c}(z)…

High-quality optical rotation curves for a sample of low-luminosity spirals evidence that the dark halos around galaxies are inconsistent with the output of proper CDM simulations. In fact, dark halos enveloping stellar disks are structures…

Based on N-body simulations, we show that realistic galactic disks are subject to bending instabilities of fire-hose type when the disks are substantially self-gravitating, that is, if they contain dark matter distributed in the disk.…

Unveiling the 3D shape of the Milky Way's dark-matter halo is critical to understanding its formation history. We created an innovative dynamical model with minimal assumptions on the internal dynamical structures and accommodates a highly…

We present a dynamical model for the formation and evolution of a massive disk galaxy, within a growing dark halo whose mass evolves according to cosmological simulations of structure formation. The galactic evolution is simulated with a…

We study the behaviors of galactic disks in triaxial halos both numerically and analytically to see if warps can be excited and sustained in triaxial potentials. We consider the following two scenarios: 1) galactic disks that are initially…

Bars and spiral arms have played an important role as constraints on the dynamics and on the distribution of dark matter in the optical parts of disk galaxies. Dynamics linked to the dissipative nature of gas, and its transformation into…

Previous studies have shown that disk warps can result from galaxy mergers. Recent research indicates a noticeable decline in the rotation curve (RC) of the Milky Way (MW), suggesting the need for a new low-mass model to describe its…