Related papers: Universal void density profiles from simulation an…
Generally, merger likelihood increases in denser environments; however, the large relative velocities at the centres of dense clusters are expected to reduce the likelihood of mergers for satellite galaxies. Tidal features probe the recent…
Cosmic voids offer an extraordinary opportunity to study the effects of massive neutrinos on cosmological scales. Because they are freely streaming, neutrinos can penetrate the interior of voids more easily than cold dark matter or baryons,…
In hierarchical models of galaxy formation, stellar tidal streams are expected around most, if not all, galaxies. Although these features may provide useful diagnostics of the $\Lambda$CDM model, their observational properties remain poorly…
The cross-correlation of cosmic voids with the lensing convergence ($\kappa$) map of the Cosmic Microwave Background (CMB) fluctuations provides a powerful tool to refine our understanding of the cosmological model. However, several studies…
For the 2dFGRS we study the properties of voids and of fainter galaxies within voids that are defined by brighter galaxies. Our results are compared with simulated galaxy catalogues from the Millenium simulation coupled with a…
Cosmic voids contain higher-order cosmological information and are of interest for astroparticle physics. Finding genuine matter underdensities in sparse galaxy surveys is, however, an underconstrained problem. Traditional void finding…
We propose a novel technique to probe the expansion history of the Universe based on the clustering statistics of cosmic voids. In particular, we compute their two-point statistics in redshift space on the basis of realistic mock galaxy…
Galaxies in cosmic voids have been reported with properties related to a delayed evolution with respect to the Universe in general. These characteristics reflect the interaction of galaxies with the environment. However, it is not clear the…
The redshift-space distortion (RSD) of galaxies surrounding massive clusters is emerging as a promising testbed for theories of modified gravity. Conventional applications of this method rely upon the assumption that the velocity field in…
Spectral energy distribution (SED) modeling is one of the main methods to estimate galaxy properties, such as photometric redshifts, $z$, and stellar masses, $M_*$, for extragalactic imaging surveys. SEDs are currently modeled as light from…
We analyze quasi-2-dimensional slices of the SDSS EDR. Gaussian smoothing with weighting by the inverse of the selection function provides 2D density fields across the full survey depth. Superclusters (SC) are characterized by a percolation…
We critically investigate current statistical tests applied to high redshift clusters of galaxies in order to test the standard cosmological model and describe their range of validity. We carefully compare a sample of high-redshift,…
The integrated Sachs-Wolfe imprint of extreme structures in the cosmic web probes the dynamical nature of dark energy. Looking through typical cosmic voids, no anomalous signal has been reported. On the contrary, supervoids, associated with…
To date, galaxy image simulations for weak lensing surveys usually approximate the light profiles of all galaxies as a single or double S\'ersic profile, neglecting the influence of galaxy substructures and morphologies deviating from such…
We develop a novel abundance matching method to construct a mock catalog of luminous red galaxies (LRGs) in SDSS, using catalogs of halos and subhalos in N-body simulations for a LCDM model. Motivated by observations suggesting that LRGs…
Tidal features provide signatures of recent mergers and offer a unique insight into the assembly history of galaxies. The Vera C. Rubin Observatory's Legacy Survey of Space and Time (LSST) will enable an unprecedentedly large survey of…
Modern redshift surveys are tasked with mapping out the galaxy distribution over enormous distance scales. Existing hydrodynamical simulations, however, do not reach the volumes needed to match upcoming surveys. We present results for the…
We present a systematic comparison of several existing and new void finding algorithms, focusing on their potential power to test a particular class of modified gravity models - chameleon $f(R)$ gravity. These models deviate from standard…
In the standard picture of cosmology, the galaxies reside in dark matter (DM) halos. DM halos are distributed in the cosmic web in different environments. The luminosity of the galaxies in different environments can be used as a probe to…
We present a new catalogue of 55,121 groups and clusters centred on Luminous Red Galaxies from SDSS DR7 in the redshift range 0.15<z<0.4. We provide halo mass estimates for each of these groups derived from a calibration between the optical…