Related papers: Probing Density Fluctuations using the FIRST Radio…
We study the effect of diffuse intracluster light on the critical surface mass density estimated from photometric redshifts of lensing source galaxies, and the resulting bias in a weak lensing measurement of galaxy cluster mass. Under…
A comprehensive search for variable and transient radio sources has been conducted using ~55,000 snapshot images of the FIRST survey. We present an analysis leading to the discovery of 1,627 variable and transient objects down to mJy levels…
The Australia Telescope Compact Array (ATCA) has been used at 1.38 and 2.38 GHz to survey seven southern Abell clusters of galaxies with high X-ray luminosities: A2746, A2837, A3126, A3216, A3230, A3827 and A3836. The clusters have also…
The flux density from undetected sources in the observing beam of a telescope produces source confusion noise in the resulting maps of the sky, and thus limits sensitivity. In a recent paper we discussed this effect in the…
The E/SO sequence of a cluster defines a boundary redward of which a reliable weak lensing signal can be obtained from background galaxies, uncontaminated by cluster members. For bluer colors, both background and cluster members are…
We propose a machine-learning-based technique to determine the number density of radio sources as a function of their flux density, for use in next-generation radio surveys. The method uses a convolutional neural network trained on…
We investigate a spatially-flat cold dark matter model (with the matter density parameter $\Omega_m=0.3$) with a primordial feature in the initial power spectrum. We assume that there is a bump in the power spectrum of density fluctuations…
Gravitational waves from inspiraling compact binaries provide direct measurements of luminosity distances and serve as a powerful probe of the high-redshift Universe. In addition to their role as standard sirens, they offer an opportunity…
In recent years, the availability of large, complete cluster samples has enabled numerous cosmological parameter inference analyses using cluster number counts. These have provided constraints on the cosmic matter density $\Omega_m$ and the…
This is the first in a series of papers on the weak lensing effect caused by clusters of galaxies in Sloan Digital Sky Survey. The photometrically selected cluster sample, known as MaxBCG, includes ~130,000 objects between redshift 0.1 and…
Precision astrometry offers a way to probe new physics. By measuring the angular position of light sources at unprecedented precision, astrometry could probe minuscule fluctuations of underlying spacetime. This work explores the possibility…
We present clustering measurements for samples of galaxies selected by morphological type and luminosity from the recently completed Stromlo-APM Redshift Survey. Early type galaxies are clustered more strongly by a factor 3.5--5.5, than…
We present a survey of mass profiles and mass-to-light ratios of eight typical galaxy clusters at a common redshift (z ~ 0.2). We use weak gravitational lensing as a probe because it is unique in avoiding any assumptions about the dynamical…
The aim of this work is to study the anisotropic weak lensing signal associated with the mass distribution of massive clusters of galaxies using the Cosmic Microwave Background (CMB) data. For this purpose, we stack patches of the Planck…
We discuss the first results from the Faint Sky Variability Survey (Groot et al. 2000). The data consist of V-band light curves, BVI colours, astrometry, and morphology information on several hundred thousand point and extended sources in…
Refractive scintillation effects are powerful techniques for discriminating between different models proposed for the electron density fluctuation spectrum in the ISM. Data from our long-term scintillation study of 18 pulsars in the DM…
Investigations of the cluster environment of radio sources have not shown a correlation between radio power and degree of clustering. However, it has been demonstrated that extended X-ray luminosity and galaxy clustering do exhibit a…
Context. Weak lensing and clustering statistics beyond two-point functions can capture non-Gaussian information about the matter density field, thereby improving the constraints on cosmological parameters relative to the mainstream methods…
Upcoming surveys with new radio observatories such as the Square Kilometer Array will generate a wealth of imaging data containing large numbers of radio galaxies. Different classes of radio galaxies can be used as tracers of the cosmic…
Next-generation galaxy surveys will be able to measure perturbations on scales beyond the equality scale. On these ultra-large scales, primordial non-Gaussianity leaves signatures that can shed light on the mechanism by which perturbations…