Related papers: Boosting the 21 cm forest signals by the clumpy su…
We investigate the possibility of using the cross-correlation of the Lyman-alpha forest and redshifted 21-cm emission to detect the baryon acoustic oscillation (BAO). The standard Fisher matrix formalism is used to determine the accuracy…
A dark-matter-only Horizon Project simulation is used to investigate the environment- and redshift- dependence of accretion onto both halos and subhalos. These objects grow in the simulation via mergers and via accretion of diffuse non-halo…
The star-forming reservoir in the distant Universe can be detected through HI 21-cm absorption arising from either cool gas associated with a radio source or from within a galaxy intervening the sight-line to the continuum source. In order…
Observations of multiple-image gravitational lens systems suggest that the projected mass distributions of galaxy haloes may contain substantial inhomogeneities. The fraction of the halo mass in dense substructure is still highly uncertain,…
As searches for thermal and self-annihilating dark matter (DM) intensify, it becomes crucial to include as many relevant physical processes and ingredients as possible to refine signal predictions, in particular those which directly relate…
I review recent results on the spatial distribution of substructure in CDM halos. I show that the spatial distribution of subhalos is anisotropic and generally prolate with a long axis that is closely aligned with the long axis of the total…
Searches for "dark" subhaloes in gamma-ray point-like source catalogues are among promising strategies for indirect dark matter detection. Such a search is nevertheless affected by uncertainties related, on the one hand, to the modelling of…
In a previous paper, we described a new method for including detailed information about substructure in semi-analytic models of halo formation based on merger trees. In this paper, we compare the predictions of our model with results from…
We track subhalo orbits of galaxy and group sized halos in cosmological simulations. We identify filamentary structures around halos and we use these to define a sample of subhalos accreted from filaments as well as a control sample of…
We describe a new algorithm for finding substructures within dark matter haloes from N-body simulations. The algorithm relies upon the fact that dynamically distinct substructures in a halo will have a {\em local} velocity distribution that…
We adopt the two point correlation function (2PCF) as a statistical tool to quantify the spatial clustering of halo stars, for galaxy systems spanning a wide range in host halo virial mass ($11.25<\log_{10}M_{200c}/\mathrm{M}_\odot<15$) and…
The balance of evidence indicates that individual galaxies and groups or clusters of galaxies are embedded in enormous distributions of cold, weakly interacting dark matter. These dark matter 'halos' provide the scaffolding for all luminous…
Cosmological structure formation predicts that our galactic halo contains an enormous hierarchy of substructures and streams, the remnants of the merging hierarchy that began with tiny Earth mass microhalos. If these structures persist…
This paper explores the impact of primordial black holes (PBHs) on the abundance of low-mass haloes and subhaloes in the dark and low-stellar-mass regime, and examines how these effects can be measured through fluctuations in strong lensing…
Prior to the epoch of reionisation, the 21-cm signal of the cosmic dawn is dominated by the Lyman-$\alpha$ coupling and gas temperature fluctuations caused by the first sources of radiation. While early efforts to model this epoch relied on…
The correlations between dark matter halo properties and subhalo abundance, or occupation, have been studied extensively; however, existing studies have mainly focused on subhalos within the virial radius of the host halo. In this work, we…
We use numerical simulations to examine the substructure within galactic and cluster mass halos that form within a hierarchical universe. Clusters are easily reproduced with a steep mass spectrum of thousands of substructure clumps that…
The cosmic microwave background absorption intensity in the 21 cm line of neutral hydrogen in the presence of additional power in the form of a "bump" in the spectrum of cosmological density perturbations is calculated. The main…
The 21 cm signal from cosmic hydrogen is one of the most propitious probes of the early Universe. The detection of this signal would reveal key information about the first stars, the nature of dark matter, and early structure formation. We…
High- to ultrahigh-redshift clustering of halos provides a powerful tool to understand cosmology and galaxy formation. However, theoretical predictions are not firmly established in the first billion years, where current and upcoming…