相关论文: Supercluster Properties as a Cosmological Probe
The density and velocity fields as extracted from the Abell/ACO clusters are compared to the corresponding fields recovered by the POTENT method from the Mark~III peculiar velocities of galaxies. In order to minimize non-linear effects and…
The connection of cluster mergers with the presence of extended, diffuse radio sources in galaxy clusters is still debated. An interesting case is the rich, merging cluster Abell 520, containing a radio halo. A recent gravitational analysis…
Observations reveal that on large scales the universe is spanned by a percolating network of superclusters interspersed with large and almost empty regions -- voids. This thesis reports the construction of a sophisticated computational…
The alignment of clusters of galaxies with their nearest neighbours and between clusters within a supercluster is investigated using simulations of 512^{3} dark matter particles for \LambdaCDM and \tauCDM cosmological models. Strongly…
Galaxy groups and clusters are the main tools used to test cosmological models and to study the environmental effect of galaxy formation. This work provides a catalogue of galaxy groups and clusters, as well as potentially merging systems…
We study the rotational motion of the galaxy cluster Abell 2107 at redshift z = 0.04 and its connection to nearby large-scale structures using a large amount of spectroscopic redshift data. By combining 978 new redshifts from the…
We present a study of morphologies, based on deep $u^{*}g^{\prime}i^{\prime}z^{\prime}$ imaging of the Virgo Cluster from the Next Generation Virgo Cluster Survey (NGVS), for 3689 Virgo cluster members spanning a mass range of…
Luminous stars in background galaxies straddling the lensing caustic of a foreground galaxy cluster can be individually detected due to extreme magnification factors of $\sim 10^2$--$10^3$, as recently observed in deep HST images. We…
We present a morphological analysis of distant field galaxies using the deep ACS images from the public parallel NICMOS observations of the Hubble Ultra Deep Field obtained in the F435W (B), F606W (V), F775W (i) and F850LP (z) filters. We…
We present a technique to construct a fair sample of simulated galaxy clusters, and build such a sample for a specific cosmological structure formation scenario. Conventionally one extracts such a sample from a single low-resolution…
The structure formation of the dense interstellar material and the fragmentation of clumps into cores is a fundamental step to understand how stars and stellar clusters form. We aim to establish a statistical view of clump fragmentation at…
We present an algorithm designed to identify galaxy (proto)clusters in wide-area photometric surveys by first selecting their dominant galaxy-i.e., the Brightest Cluster Galaxy (BCG) or protoBCG-through the local stellar mass density traced…
We present a study of galaxies in the STAGES survey of the Abell 901/902 supercluster at z~0.165, based on HST ACS F606W, COMBO-17, Spitzer 24um, XMM-Newton X-ray, and gravitational lensing maps. We characterize galaxies with strong,…
We study the tomographic clustering properties of the photometric cluster catalogue derived from the Third Data Release of the Kilo Degree Survey, focusing on the angular correlation function and its spherical harmonic counterpart, the…
Current efforts in observational cosmology are focused on characterizing the mass-energy content of the Universe. We present results from a geometric test based on strong lensing in galaxy clusters. Based on Hubble Space Telescope images…
We use an approach to estimate galaxy morphologies based on an ellipticity (e) vs. Bulge-to-Total ratio (B/T) plane. We have calibrated this plane by comparing with Dressler's classifications. With the aid of our calibration, we have…
We present distribution functions and spatial correlations of the shapes of dark matter halos derived from Hubble Volume simulations of a LambdaCDM universe. We measure both position and velocity shapes within spheres encompassing mean…
The galaxy cluster Abell 2152 is recently found to be forming a cluster-cluster system with another, more distant cluster whose core is almost perfectly aligned to that of A2152. We discuss the detectability of microlensing events where a…
The distribution of Abell clusters of galaxies is analysed to study the regularity of the supercluster-void network. A new geometric method sensitive to the regularity of the location of clusters is applied. We find that the…
We use a suite of high resolution molecular cloud simulations carried out with the moving mesh code Arepo to explore the nature of star-forming filaments. The simulated filaments are identified and categorised from column density maps in…