Related papers: A Natural Supersymmetric Model with MeV Dark Matte…
Galactic weak-scale Dark Matter (DM) particles annihilating into lepton-rich channels not only produce gamma-rays via prompt radiation but also generate abundant energetic electrons and positrons, which subsequently emit through…
The direct detection of Dark Matter particles with mass below the GeV-scale is hampered by soft nuclear recoil energies and finite detector thresholds. For a given maximum relative velocity, the kinematics of elastic Dark Matter nucleus…
We discuss the phenomenology of an MeV-scale Dirac fermion coupled to the Standard Model through a dark photon with kinetic mixing with the electromagnetic field. We compute the dark matter relic density and explore the interplay of direct…
We explore the $511$~keV emission associated to sub-GeV dark matter (DM) particles that can produce electron-positron pairs and form positronium after thermalizing. We use $\sim16$~yr of SPI data from INTEGRAL to constrain DM properties,…
It is well known that stable weak scale particles are viable dark matter candidates since the annihilation cross section is naturally about the right magnitude to leave the correct thermal residual abundance. Many dark matter searches have…
We survey operators that can lead to a keV photon line from dark matter decay or annihilation. We are motivated in part by recent claims of an unexplained 3.5 keV line in galaxy clusters and in Andromeda, but our results could apply to any…
We study the direct detection prospects for a representative set of simplified models of sub-GeV dark matter (DM), accounting for existing terrestrial, astrophysical and cosmological constraints. We focus on dark matter lighter than an MeV,…
Neutrino masses and light (keV-GeV) sterile neutrinos can arise naturally via a modified, low energy seesaw mechanism if the right-handed neutrinos are charged under a new symmetry broken by a PeV scale vacuum expectation value, presumably…
We present a simple extension of the standard model that gives rise to baryogenesis a has a dark matter candidate of O(GeV) mass. A minimal set of new fields required for baryogenesis includes two O(TeV) colored scalars and a singlet…
Asymmetric Dark Matter (ADM) models invoke a particle-antiparticle asymmetry, similar to the one observed in the Baryon sector, to account for the Dark Matter (DM) abundance. Both asymmetries are usually generated by the same mechanism and…
"Dark Photons", light new vector particles V kinetically mixed with the photon, are a frequently considered extension of the Standard Model. For masses below 10 keV they are emitted from the solar interior. In the limit of small mass m_V…
Tentative evidence for excess GeV-scale gamma rays from the galactic center has been corroborated by several groups, including the Fermi collaboration, on whose data the observation is based. Dark matter annihilation into standard model…
We study the morphology of the 511 keV signal that could be produced by exciting dark matter (XDM) in the Milky Way. In this model, collisions between dark matter particles excite the dark matter to a state that can then decay back to the…
Dark matter (DM) charged under a dark U(1) force appears in many extensions of the Standard Model, and has been invoked to explain anomalies in cosmic-ray data, as well as a self-interacting DM candidate. In this paper, we perform a…
In this paper we present a simple extension of the minimal supersymmetric standard model [MSSM] which "naturally" produces the INTEGRAL photon signal. The model can be embedded in an SU(5) grand unified theory [GUT] with gauge mediated SUSY…
It has recently been pointed out that the 511 keV emission line detected by Integral/SPI from the bulge of our galaxy could be explained by annihilations of light Dark Matter particles into e^+ e^-. If such a signature is confirmed, then…
If the minimal supersymmetric standard model (MSSM) is the only new physics around the TeV-scale, it has to account for the entire dark matter relic density, or else it will cease to be `minimal'. We use this expectation to obtain the best…
In a previous work, it was found that the Light Dark Matter (LDM) scenario could be a possible explanation to the 511 keV emission line detected at the centre of our galaxy. Here, we show that hints of this scenario may also have been…
While star-forming galaxies could be major contributors to the cosmic GeV $\gamma$-ray background, they are expected to be MeV-dim because of the "pion bump" falling off below ~100 MeV. However, there are very few observations of galaxies…
Cosmic ray anomalies observed by PAMELA and Fermi-LAT experiments may be interpreted by heavy (TeV-scale) dark matter annihilation enhanced by Sommerfeld effects mediated by a very light (sub-GeV) U(1)_X gauge boson, while the recent direct…