Related papers: Cusp-core problem and strong gravitational lensing
The cold dark matter (CDM) cosmological model has been remarkably successful in explaining cosmic structure over an enormous span of redshift, but it has faced persistent challenges from observations that probe the innermost regions of dark…
Within the framework of the cold dark matter (CDM) cosmogony, a central cusp in the density profiles of virialized dark haloes is predicted. This prediction disagrees with the soft inner halo mass distribution inferred from observations of…
The core-cusp problem remains as a challenging discrepancy between observations and simulations in the standard $\Lambda$CDM model for the formation of galaxies. The problem is that $\Lambda$CDM simulations predict a steep power-law mass…
Rotation curves of galaxies probe their total mass distributions, including dark matter. Dwarf galaxies are excellent systems to investigate the dark matter density distribution, as they tend to have larger fractions of dark matter compared…
The standard cosmological model, now strongly constrained by direct observation at early epochs, is very successful in describing the structure of the evolved universe on large and intermediate scales. Unfortunately, serious contradictions…
For almost two decades the properties of "dwarf" galaxies have challenged the Cold Dark Matter (CDM) paradigm of galaxy formation. Most observed dwarf galaxies consists of a rotating stellar disc embedded in a massive DM halo with a near…
Low Surface Brightness (LSB) galaxies are dominated by dark matter, and their rotation curves thus reflect their dark matter distribution. Recent high-resolution rotation curves suggest that their dark matter mass-density distributions are…
We make a direct comparison of the derived dark matter (DM) distributions between hydrodynamical simulations of dwarf galaxies assuming a LCDM cosmology and the observed dwarf galaxies sample from the THINGS survey in terms of (1) the…
Cold Dark Matter (CDM) has become the standard modern theory of cosmological structure formation. Its predictions appear to be in good agreement with data on large scales, and it naturally accounts for many properties of galaxies. But…
Recent cosmological hydrodynamical simulations suggest that baryonic processes, and in particular supernova feedback after bursts of star formation, can alter the structure of dark matter haloes and transform primordial cusps into shallower…
We calculate the energy that baryons must inject in cold dark matter (CDM) haloes in order to remove centrally-divergent DM cusps on scales relevant to observations of dwarf spheroidal galaxies (dSphs). We estimate that the CDM haloes often…
We propose a solution of the cusp problem in framework of the standard $\Lambda$CDM cosmology. To do this we describe the linear and nonlinear periods of halo formation by the entropy function of dark matter particles. This approach allows…
While N-body simulations testify for a cuspy profile of the central region of the dark matter haloes, observations favor a shallow, cored density profile of the central region of, at least, some spiral galaxies and dwarf spheroidals. We…
The cold dark matter model of structure formation faces apparent problems on galactic scales. Several threads point to excessive halo concentration, including central densities that rise too steeply with decreasing radius. Yet, random…
We present more results from a fully cosmological LCDM simulation of a group of isolated dwarf galaxies that has been shown to reproduce the observed stellar mass and cold gas content, resolved star formation histories, and metallicities of…
Observations on galactic scales seem to be in contradiction with recent high resolution N-body simulations. This so-called cold dark matter (CDM) crisis has been addressed in several ways, ranging from a change in fundamental physics by…
We use N-body simulations to examine the effects of mass outflows on the density profiles of cold dark matter (CDM) halos surrounding dwarf galaxies. In particular, we investigate the consequences of supernova-driven winds that expel a…
We use cosmological hydrodynamical galaxy formation simulations from the NIHAO project to investigate the response of cold dark matter (CDM) haloes to baryonic processes. Previous work has shown that the halo response is primarily a…
Recent observations have been discovering new ultra-faint dwarf galaxies as small as $\sim20~{\rm pc}$ in half-light radius and $\sim3~{\rm km~s^{-1}}$ in line-of-sight velocity dispersion. In these galaxies, dynamical friction on a star…
We examine the circular velocity profiles of galaxies in {\Lambda}CDM cosmological hydrodynamical simulations from the EAGLE and LOCAL GROUPS projects and compare them with a compilation of observed rotation curves of galaxies spanning a…