Related papers: Massive prompt cusps: A new signature of warm dark…
Every dark matter halo forms with a $\rho\propto r^{-1.5}$ density cusp at its center. For warm dark matter (WDM), these prompt cusps can be massive enough to influence the kinematics of dwarf galaxies. By implementing prompt cusps in the…
As the first dark matter objects gravitationally condense, a density cusp forms immediately at every initial density maximum. Numerical simulations and theoretical arguments suggest that these prompt cusps can survive until the present day.…
Simulations have established that each halo of collisionless dark matter is expected to contain a $\rho = A r^{-1.5}$ density cusp at its center. This prompt cusp is a relic of the halo's earliest moments and has a mass comparable to the…
Prompt $\rho\propto r^{-1.5}$ density cusps are the densest and most abundant dark matter systems. If the dark matter is a weakly interacting massive particle (WIMP), recent studies have shown that prompt cusps dominate the aggregate dark…
Prompt cusps are the densest quasi-equilibrium dark matter objects; one forms at the instant of collapse within every isolated peak of the initial cosmological density field. They have power-law density profiles, $\rho \propto r^{-1.5}$…
The first generation of haloes forms from the collapse of the smallest peaks in the initial density field. $N$-body simulations of this process suggest a prompt formation of a steep power-law cusp, but these calculations are plagued by…
Gravitational potential fluctuations driven by bursty star formation can kinematically 'heat up' dark matter at the centres of dwarf galaxies. A key prediction of such models is that, at a fixed dark matter halo mass, dwarfs with a higher…
The Cold Dark Matter paradigm successfully explains many phenomena on scales larger than galaxies, but seems to predict galaxy halos which are more centrally concentrated and have a lumpier substructure than observed. Endowing cosmic dark…
Simulations of the clustering of cold dark matter yield dark-matter halos that have central density cusps, but observations of totally dark-matter dominated dwarf spheroidal galaxies imply that they do not have cuspy central density…
For nearly 40 years, dark matter has been widely assumed to be cold and collisionless. Cold dark matter models make fundamental predictions for the behavior of dark matter on small (<10 kpc) scales. These predictions include cuspy density…
I present an analytic model for the early post-collapse evolution of a spherical density peak on the coherence scale of the initial fluctuations in a universe filled with collisionless and pressure-free "dust". On a time-scale which is…
Well-motivated elementary particle candidates for the dark matter, such as the sterile neutrino, behave as warm dark matter (WDM).For particle masses of order a keV, free streaming produces a cutoff in the linear fluctuation power spectrum…
Detecting dark matter as it streams through detectors on Earth relies on knowledge of its phase space density on a scale comparable to the size of our solar system. Numerical simulations predict that our Galactic halo contains an enormous…
Warm Dark Matter (WDM) particles with masses ($\sim$ kilo electronvolt) offer an attractive solution to the small-scale issues faced by the Cold Dark Matter (CDM) paradigm. The delay of structure formation in WDM models and the associated…
Dark matter (DM) haloes forming near the thermal cut-off scale of the density perturbations are unique, since they are the smallest objects and form through monolithic gravitational collapse, while larger haloes contrastingly have…
The internal structure of dark matter haloes encodes their assembly history and offers critical insight into the nature of dark matter and structure formation. Analytical studies and high-resolution simulations have recently predicted the…
Observed cusps with density profiles $\rho\propto r^{-1}$ or shallower, in the central regions of galaxies, cannot be reproduced in the standard Cold Dark Matter (CDM) picture of hierarchical clustering. Previous claims to the contrary were…
The distribution of dark matter around galactic or cluster halos has usually been assumed to be approximately isothermal with a non-zero core radius, which is expected to be of the order of the size of the visible matter distribution.…
We investigate the structure of the dark matter halo formed in the cold dark matter scenario using $N$-body simulations. We simulated 12 halos with the mass of $6.6\times 10^{11}M_{\odot}$ to $8.0\times 10^{14}M_{\odot}$. In almost all…
The free streaming of warm dark matter particles dampens the fluctuation spectrum, flattens the mass function of haloes and imprints a fine grained phase density limit for dark matter structures. The phase space density limit is expected to…