Related papers: Dark Matter Self-Interactions and Light Force Carr…
The properties of the dark matter that determine its thermal relic abundance can be very different from the dark matter properties today. We investigate this possibility by coupling a dark matter sector to a scalar that undergoes a phase…
Accelerated expansion of the Universe may result from an anti-frictional force that is self-consistently exerted on cold dark matter (CDM). Cosmic anti-friction is shown to give rise to an effective negative pressure of the cosmic medium.…
Current multi-ton detectors put stringent constraints on the GeV-scale galactic dark matter, pushing the allowed cross-section almost towards the neutrino fog, yet remain mostly insensitive to the light dark matter. Cosmic rays can…
Dark matter (DM) particle annihilation or decay can produce monochromatic $\gamma$-rays readily distinguishable from astrophysical sources. $\gamma$-ray line limits from 30 GeV to 200 GeV obtained from 11 months of Fermi Large Area Space…
If the astronomical dark matter is made of weakly interacting, massive and stable species, it should annihilate on itself into particles. This process should produce rare antimatter cosmic rays and lead to distortions in their energy…
In some scenarios, the dark matter relic abundance is set by the semi-annihilation of two dark matter particles into one dark matter particle and one Standard Model particle. These semi-annihilations might still be occurring today in the…
We estimate the rate of dark matter scattering in collapsed structures throughout the history of the Universe. If the scattering cross-section is velocity-independent, then the canonical picture is correct that scatterings occur mainly at…
Although empirical evidence indicates that that the universe's gas had become ionized by redshift z ~ 6, the mechanism by which this transition occurred remains unclear. In this article, we explore the possibility that dark matter…
Much attention has been given to dark matter explanations of the PAMELA positron fraction and Fermi electronic excesses. For those theories with a TeV-scale WIMP annihilating through a light force-carrier, the associated Sommerfeld…
Several cosmic ray experiments have measured excesses in electrons and positrons, relative to standard backgrounds, for energies from ~ 10 GeV - 1 TeV. These excesses could be due to new astrophysical sources, but an explanation in which…
We study direct detection bounds on cosmic ray-upscattered dark matter in simplified models including light mediators. We find that the energy dependence in the scattering cross section is significant, and produces stronger bounds than…
Annihilation of dark matter particles in cosmological halos (including a halo of the Milky Way) contributes to the diffuse gamma-ray background (DGRB). As this contribution will appear anisotropic in the sky, one can use the angular power…
A massive black hole is present at the centre of our galaxy and inevitably accretes dark matter particles, creating a region of very high particle density. The annihilation rate is enhanced with a large number of e+e- pairs produced either…
Dark matter particles could annihilate into light and metastable mediators subsequently decaying far away from where they are produced. In this scenario, the indirect signatures of dark matter are altered with respect to the conventional…
Traditional direct detection experiments lack the sensitivity to probe the sub-GeV dark matter (DM), primarily due to the low energy of the expected nuclear recoils. In this work, we investigate cosmic-ray (CR) upscattering as a mechanism…
Recent preliminary results from the PAMELA experiment indicate the presence of an excess of cosmic ray positrons above 10 GeV. In this letter, we consider possibility that this signal is the result of dark matter annihilations taking place…
The detailed origin of the diffuse gamma-ray background is still unknown. However, the contribution of unresolved sources is expected to induce small-scale anisotropies in this emission, which may provide a way to identify and constrain the…
We study the evolution of cosmological perturbations in dark-matter models with elastic and velocity-independent self interactions. Such interactions are imprinted in the matter-power spectrum as dark acoustic oscillations, which can be…
We investigate the dark matter annihilation in the brane-world and quintessence scenarios, in which the modified cosmological expansion rate can enhance the thermal relic density of dark matter. According to the observed dark matter…
The light mediator scenario of self-interacting dark matter is strongly constrained in many ways. After summarizing the various constraints, we discuss minimal options and models which allow to nevertheless satisfy all these constraints.…