Related papers: Cluster density slopes from Dark Matter-Baryons En…
We examine a sample of $\sim 250 000$ "locally brightest galaxies" selected from the Sloan Digital Sky Survey to be central galaxies within their dark matter halos. These were previously stacked by the Planck Collaboration to measure the…
We present the integrated mass profiles for a sample of ten nearby (z<=0.15), relaxed galaxy clusters, covering a temperature range of [2-9]keV, observed with XMM-Newton. The mass profiles were derived from the observed gas density and…
I propose a modification of the spherical infall model for the evolution of density fluctuations with initially Gaussian probability distribution and scale-free power spectra in Einstein-de Sitter universe as developed by Hoffman & Shaham.…
The active galactic nuclei (AGNs) are widely believed to be one of the promising acceleration sites of ultrahigh-energy cosmic rays (CRs). Essentially, AGNs are powered by the gravitational energy of matter falling to supermassive black…
According to the now strongly supported concordance $\Lambda$CDM model, galaxies may be grossly described as a luminous component embedded in a dark matter halo. The density profile of these mass dominating haloes may be determined by N -…
Modified Newtonian Dynamics (MOND) has long been known to fail in galaxy clusters, implying a residual missing mass problem for clusters in this context. Here, using mass profiles derived from strong- and weak-lensing shear, as well as…
Using high-accuracy rotation curves of spiral galaxies, we derive distributions of the surface mass density. Comparing with the luminosity profiles, we show that the dark mass in disk and bulge distributions follows those of luminous…
[Abridged] The relatively recent insight that energy input from supermassive black holes (BHs) can have a substantial effect on the star formation rates (SFRs) of galaxies motivates us to examine its effects on the scale of galaxy groups.…
We test the predictions of Emergent Gravity using matter densities of relaxed, massive clusters of galaxies using observations from optical and X-ray wavebands. We improve upon previous work in this area by including the baryon mass…
We explain the M-sigma relation between the mass of super massive black holes in galaxies and the velocity dispersions of their bulges in the scalar field or the Bose-Einstein condensate dark matter model. The gravity of the central black…
If the mean properties of clusters of galaxies are well described by the entropy-driven model, the distortion induced by the cluster population on the blackbody spectrum of the Cosmic Microwave Background radiation is proportional to the…
Observed variations in the IMF are reviewed with an emphasis on environmental density. The remote field IMF studied in the LMC by several authors is clearly steeper than most cluster IMFs, which have slopes close to the Salpeter value.…
At which masses does the regime of globular clusters end and the one of dwarf galaxies begin? And what separates these two classes of hot stellar systems? We examine to what extend very massive (>10^7 Mo) young star clusters are similar to…
How is mass distributed in the Universe? How does it compare with the distribution of light and stars? We address these questions by examining the distribution of mass, determined from weak lensing observations, and starlight, around…
We analyse the results of an Eulerian AMR cosmological simulation in order to quantify the mass growth of galaxy clusters, exploring the differences between dark matter and baryons. We have determined the mass assembly histories (MAHs) of…
Galaxy clusters, the most massive, dark-matter-dominated, and most recently assembled structures in the Universe, are key tools for probing cosmology. However, uncertainties in scaling relations that connect cluster mass to observables like…
We present new constraints on the density profiles of dark matter (DM) halos in seven nearby dwarf galaxies from measurements of their integrated stellar light and gas kinematics. The gas kinematics of low mass galaxies frequently suggest…
Heavy particles in galaxy clusters tend to be more centrally concentrated than light ones according to the Boltzmann distribution. An estimate of the drift velocity suggests that it is possible that the helium nuclei may have entirely or…
Through a suite of direct N-body simulations, we explore how the structural and kinematic evolution of a star cluster located at the center of a dwarf galaxy is affected by the shape of its host's dark matter density profile. The stronger…
I re-examine the relation between virial mass and concentration for groups and clusters of galaxies as measured in a number of recent works. As previously noted by several authors, low-mass clusters and groups of galaxies display…