Related papers: Effects of galaxy-halo alignment and adiabatic con…
We study the shapes of galaxy dark matter haloes by measuring the anisotropy of the weak gravitational lensing signal around galaxies in the second Red-sequence Cluster Survey (RCS2). We determine the average shear anisotropy within the…
We present a simple technique to estimate mass-to-light (M/L) ratios of stellar populations based on two broadband photometry measurements, i.e. a color-M/L relation. We apply the color-M/L relation to galaxy rotation curves, using a large…
We show how observations of multiply-imaged quasars at high redshift can be used as a probe of dark matter clumps (subhalos with masses ~ 10^9 solar masses) within the virialized extent of more massive lensing halos. A large abundance of…
We study the efficiency of numerically simulated galaxy clusters for producing strong gravitational lensing events in different dark-energy cosmologies with constant and time-variable equation of state and we compare it with ``standard''…
Here I summarize constraints on the nature of the dark matter halos of field galaxies that have been obtained from the most recent investigations of (i) weak galaxy-galaxy lensing and (ii) the dynamics of satellite galaxies in orbit about…
In the present paper, we improve the "Extended Secondary Infall Model" (ESIM) of Williams et al. (2004) to obtain further insights on the cusp/core problem. The model takes into account the effect of ordered and random angular momentum,…
The concordance cosmological model based on cold dark matter makes definitive predictions for the growth of galaxies in the Universe, which are being actively studied using numerical simulations. These predictions appear to contradict the…
The mass-concentration relation of dark matter halos reflects the assembly history of objects in hierarchical structure formation scenarios, and depends on fundamental quantities in cosmology such as the slope of the primordial matter…
The statistics of gravitational lensing can provide us with a very powerful probe of the mass distribution of matter in the universe. By comparing predicted strong lensing probabilities with observations, we can test the mass distribution…
The gravitational lensing properties of cosmological halos depend upon the mass distribution within each halo. The description of halos as nonsingular, truncated isothermal spheres, a particular solution of the isothermal Lane-Emden…
The properties of substructure in galaxy clusters, exquisitely probed by gravitational lensing, offer a stringent test of dark matter (DM) models. Combining strong- and weak-lensing data for massive clusters, we map their total mass --…
I elaborate on my prediction that an indirect detection of cold dark matter (CDM) may be possible by observing the gravitational lensing effects of the CDM cusp caustics at cosmological distances. Cusps in the distribution of CDM are…
Constraints on dark matter halo masses from weak gravitational lensing can be improved significantly by using additional information about the morphology of their density distribution, leading to tighter cosmological constraints derived…
We use the statistics of strong gravitational lenses to investigate whether mass profiles with a flat density core are supported. The probability for lensing by halos modeled by a nonsingular truncated isothermal sphere (NTIS) with image…
In cosmological N-body simulations, the baryon effects on the cold dark matter (CDM) halos can be used to solve the small scale problems in $\Lambda$CDM cosmology, such as cusp-core problem and missing satellites problem. It turns out that…
We present a halo model prediction of the image separation distribution of strong lenses. Our model takes account of the subhalo population, which has been ignored in previous studies, as well as the conventional halo population. Halos and…
We investigate whether the shapes of galaxy clusters inferred from weak gravitational lensing can be used as a test of the nature of dark matter. We analyse mock weak lensing data, with gravitational lenses extracted from cosmological…
Using an analytical model, we compute the distribution of image separations resulting from gravitational lensing of distant sources, for 7 COBE-normalized CDM models with various combinations of Omega_0 and lambda_0. Our model assumes that…
We consider the sensitivity of the circular-orbit adiabatic contraction approximation to the baryon condensation rate and the orbital structure of dark matter halos in the $\Lambda$CDM paradigm. Using one-dimensional hydrodynamic…
The galaxy correlation function serves as a fundamental tool for studying cosmology, galaxy formation, and the nature of dark matter. It is well established that more massive, redder and more compact galaxies tend to have stronger…