Related papers: Observational detection of correlation between gal…
While galaxies with clockwise and counterclockwise handedness are visually different, they are expected to be symmetric in all of their other characteristics. Previous experiments using both manual analysis and machine vision have shown…
The Galaxy's stellar halo seems to be a tangle of disrupted systems that have been tidally stretched out into streams. Each stream approximately delineates an orbit in the Galactic force-field. In the first paper in this series we showed…
The standard disc formation scenario postulates that disc forms as the gas cools and flows into the centre of the dark matter halo, conserving the specific angular momentum. Major mergers have been shown to be able to destroy or highly…
Observations of non-random distribution of galaxies with opposite spin directions have recently attracted considerable attention. Here, a method for identifying cosine-dependence in a dataset of galaxies annotated by their spin directions…
It has recently been argued that the observed ellipticities of galaxies may be determined at least in part by the primordial tidal gravitational field in which the galaxy formed. Long-range correlations in the tidal field could thus lead to…
The projected directions of the rotation axes of interacting binary disk galaxies tend to align orthogonal to each other. Sofue (1992) has suggested that this could be due to shorter merger times for galaxies with paralel spins. We show by…
The evolution of galaxies is driven strongly by dynamical processes including internal instabilities, tidal interactions and mergers. The cluster environment is a useful laboratory for studying these effects. I present recent results on…
Leveraging the semi-analytic method, we compute halo spins for a substantial sample of HI-bearing galaxies observed in the Arecibo Legacy Fast Alfa Survey. Our statistical analysis reveals a correlation between halo spin and environment,…
Using the SDSS spectroscopic sample, we estimate the dark matter halo spin parameter lambda for ~53,000 disk galaxies for which MOPED star formation histories are available. We investigate the relationship between spin and total stellar…
Dynamical friction and tidal disruption are effective mechanisms of evolution of globular cluster systems, especially in non-axysimmetric galaxies with a central compact nucleus. With a semi-analytical approach based on the knowledge of the…
We have analysed the distribution of inclination-corrected galaxy concentrations in the Sloan Digital Sky Survey. We find that unlike most galaxy properties, which are distributed bimodally, the distribution of concentrations is trimodal:…
Recent independent observations using several different telescope systems an analysis methods have provided evidence of parity violation between the number of galaxies that spin in opposite directions. On the other hand, other studies…
Warps are common features in both stellar and gaseous disks of nearby spiral galaxies with the latter usually easier to detect. Several theories have been proposed in the literature to explain their formation and prevalence, including tidal…
We determine the character of orbits of stars moving in the meridional plane $(R,z)$ of an axially symmetric time-independent disk galaxy model with a spherical central nucleus. In particular, we try to reveal the influence of the value of…
We present a semi-analytical model in which galaxy collisions and strong tidal interactions, both in the field and during the collapse phase of groups and clusters help determine galaxy morphology. From a semi-analytical analysis based on…
Tidal interactions between disc galaxies depend on galaxy structure, but the details of this relationship are incompletely understood. I have constructed a three-parameter grid of bulge/disc/halo models broadly consistent with $\Lambda$CDM,…
We study the alignment of galaxies relative to their local environment in SDSS-DR8 and, using these data, we discuss evolution scenarios for different types of galaxies. We defined a vector field of the direction of anisotropy of the local…
We discuss the potential cosmological role of gravitational wave astronomy as a probe of the very early universe. The next generation of detectors - now in production - may be able to observe a stochastic background of gravitational waves…
The relative orientation of clusters' major elongation axes and clusters' angular momentum is studied using a large N-body simulation in a box of 500 Mpc/h base length for a standard LambdaCDM model. Employing the technique of mark…
Until a decade ago, galaxy formation simulations were unable to simultaneously reproduce the observed angular momentum (AM) of galaxy disks and bulges. Improvements in the interstellar medium and stellar feedback modelling, together with…