相关论文: Galaxy infall models for arbitrary velocity direct…

Many spiral galaxies show a large-scale asymmetry with a cos\phi dependence in their rotation curves as well as in their morphology, such as M101 and NGC 628. We show that both these features can be explained by the response of a galactic…

The trajectories since z=4 of systems of galaxies (`halos') with cz < 8,000 km/s are found through Numerical Action reconstructions. A set of 9,719 halos from a 2MASS group catalog and Cosmicflows-3 catalogs are given attention. Present…

We explore how a realistic surface brightness detection limit of $\mu_V \approx 32.5$ mag arcsec$^{-2}$ for stars at the edges of ultra-faint galaxies affects our ability to infer their underlying properties. We use a sample of 19 galaxies…

We present a study of the statistical properties of three velocity dispersion and mass estimators, namely biweight, gapper and standard deviation, in the small number of galaxies regime ($N_{\rm gal} \le 75$). Using a set of 73 numerically…

A simple model of how objects of different masses stream towards each other as they cluster gravitationally is described. The model shows how the mean streaming velocity of dark matter particles is related to the motions of the parent dark…

We measured the ionized-gas and stellar kinematics along the major and minor axis of a sample of 10 early-type spirals. Much to our surprise we found a remarkable gas velocity gradient along the minor axis of 8 of them. According to the…

N-body simulations were conducted of pairs of galaxies with a 3:1 mass ratio on parabolic orbits, in order to quantify the effect of dynamical friction. The effects of varying the ratio of the dark matter halo size to the distance of…

The accuracy and robustness of a simple method to estimate the total mass profile of a galaxy is tested using a sample of 65 cosmological zoom-simulations of individual galaxies. The method only requires information on the optical surface…

Using a large sample of galaxies from the SDSS-DR7, we have analysed the alignment of disk galaxies around cosmic voids. We have constructed a complete sample of cosmic voids (devoid of galaxies brighter than M_r-5 log(h) =-20.17) with…

We examine the central stellar velocity dispersion of subhalos based on IllustrisTNG cosmological hydrodynamic simulations. The central velocity dispersion is a fundamental observable that links galaxies with their dark matter subhalos. We…

We estimate the vertical gradient of rotational velocity for several spiral galaxies in the framework of a global thin-disc model, using the approximation of quasi-circular orbits. We obtain gradients having a broad range of values, in…

Three three-component (bulge, disk, halo) model Galactic gravitational potentials differing by the expression for the dark matter halo are considered. The central (bulge) and disk components are described by the Miyamoto-Nagai expressions.…

The size-velocity dispersion ($\sigma$) relation, while well established for giant HII regions, remains uncertain for their smaller counterparts (physical radii R < 20 pc). Thanks to the LAMOST MRS-N dataset's large sky coverage and high…

We present internal velocity dispersion determinations from high-resolution spectroscopic observations of a sample of nine globular clusters in M31. Comprehensive numerical simulations are used to show that the typical uncertainty of our…

We give a summary of recent results on spatial and velocity biases in cosmological models. Progress in numerical techniques made it possible to simulate halos in large volumes with a such accuracy that halos survive in dense environments of…

We discuss the distribution of radial velocities of galaxies belonging to the Local Group. Two independent samples of galaxies as well as several methods of reduction from the heliocentric to the galactocentric radial velocities are…

We construct models describing the velocity field in the infall regions of clusters. The velocity field is the superposition of a systematic component and a "noise" component accounting for the effects of small scale substructure and…

To determine the relative distances and peculiar velocities of 140 groups and clusters of galaxies at low redshifts ($z$ < 0.12), we used the fundamental plane (FP) of early-type galaxies (from the Sloan Digital Sky Survey (SDSS) data). We…

We examine the evolution of the relation between stellar mass surface density, velocity dispersion and half-light radius$-$the stellar mass fundamental plane$-$for quiescent galaxies at $z<0.6$. We measure the local relation from galaxies…

Cosmological galaxy formation models predict the existence of dark matter minihalos surrounding galaxies and in filaments connecting groups of galaxies. The more massive of these minihalos are predicted to host HI gas that should be…