Cosmic transients, Einstein’s Equivalence Principle and dark matter halos

Dark-Matter-Induced Weak Equivalence Principle Violation

Weighing Dark Matter Halos with the Cosmic Microwave Background

Weighing something that is partially invisible is very challenging. But this is exactly what astronomers contend with when estimating masses of galaxies and their clusters. These structures contain significant amounts of still-mysterious dark matter residing in a “halo” extending beyond the standard, baryonic (and mostly luminous) matter. Gravitational lensing allows astronomers to get around t...

Dwarf Dark Matter Halos

We use N-body simulations to study properties of dwarf halos with virial masses in the range 10 − 10hM⊙. Unlike recent reported results, we find that the density profiles of relaxed dwarf halos are well fitted by the NFW profile and do not have cores. We estimate the distribution of concentrations for halos in mass range that covers six orders of magnitude from 10 hM⊙ to 10 13 hM⊙, and find tha...

Dark-matter-induced violation of the weak equivalence principle.

A long-range fifth force coupled to dark matter can induce a coupling to ordinary matter if the dark matter interacts with standard model fields. We consider constraints on such a scenario from both astrophysical observations and laboratory experiments. We also examine the case where the dark matter is a weakly interacting massive particle, and derive relations between the coupling to dark matt...

On Singular Dark Matter Halos

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. Recently, the possibility has been raised that dark matter halos might be singular in the sense that the dark matter density could increase monotonically with rad...