Related papers: Initial State Radiation in Majorana Dark Matter An…
We consider a fermionic dark matter (DM) particle in renormalizable Standard Model (SM) gauge interactions in a simple $t$-channel model. The DM particle interactions with SM fermions is through the exchange of scalar and vector mediators…
We consider an extension of the standard model (SM) with an inert Higgs doublet and three Majorana singlet fermions to address both origin and the smallness of neutrino masses and dark matter (DM) problems. In this setup, the lightest…
We analyze a low energy effective model of Dark Matter in which the thermal relic density is provided by a singlet Majorana fermion which interacts with the Higgs fields via higher dimensional operators. Direct detection signatures may be…
We consider dark matter annihilation into a general set of final states of Standard Model particles, including two-body and four-body final states that result from the decay of intermediate states. For dark matter masses ~10-10^5 GeV, we…
Dark Matter (DM) detection prospects at future e+e- colliders are reviewed under the assumption that DM particles are fermions of the Majorana or Dirac type. Although the discussion is quite general, one will keep in mind the recently…
We show how light spin-1/2 or spin-0 particles may be acceptable Dark Matter candidates, provided they annihilate sufficiently strongly through new interactions, such as those induced by a new light neutral spin-1 boson U. The corresponding…
We show that dark matter annihilation around the time of recombination can lead to growing ionization fraction perturbations, that track the linear collapse of matter over-densities. This amplifies small scale cosmological perturbations to…
We point out that current and planned telescopes have the potential of probing annihilating Dark Matter (DM) with a mass of O(100) TeV and beyond. As a target for such searches, we propose models where DM annihilates into lighter mediators,…
We enumerate the set of simplified models which match onto the complete set of gauge invariant effective operators up to dimension six describing interactions of a singlet-like Majorana fermion dark matter with the standard model. Tree…
The Indirect Detection of neutralino Dark Matter is most promising through annihilation channels producing a hard energy spectrum for the detected particles, such as the neutralino annihilation into $Zh$. A cancellation however makes this…
We consider a simplified model for Majorana fermion dark matter and explore constraints from direct, indirect and LHC collider searches. The dark matter is assumed to couple to the Standard Model through a vector mediator with axial-vector…
We analyze a classically scale invariant extension of the Standard Model with dark gauge $U(1)_X$ broken by doubly charge scalar $\Phi$ leaving a remnant $Z_2$ symmetry. Dark fermions are introduced as dark matter candidates and for anomaly…
Due to the standard electroweak model we have become accustomed to think about a neutrino $\nu$ and its antineutrino $\bar \nu$ as distinct particles. However, it has long been recognized that the apparent distinction between them may be…
We study the effects of dark-matter annihilation during the epoch of big-bang nucleosynthesis on the primordial abundances of light elements. We improve the calculation of the light-element abundances by taking into account the effects of…
The thermal production mechanism of dark matter is attractive and well-motivated by predictivity. A representative of this type of dark matter candidate is the canonical, weakly interacting massive particles. An alternative is…
If the neutrino is Majorana type and the electroweak phase transition is second or weak first order, neutrino-induced interactions together with sphaleron transitions have the potential to erase a previously generated baryon asymmetry of…
We extend the singlet Majoron model of dark radiation by adding another singlet scalar of unit lepton charge. The spontaneous breaking of global $U(1)_L$ connects dark radiation with neutrino mass generation via the type-I seesaw mechanism.…
It is well known that annihilations in the homogeneous fluid of dark matter (DM) can leave imprints in the cosmic microwave background (CMB) anisotropy power spectrum. However, the relevance of DM annihilations in halos for cosmological…
Dark Matter annihilation (DMA) may yield an excess of gamma rays and antimatter particles, like antiprotons and positrons, above the background from cosmic ray interactions. Several signatures, ranging from the positron excess, as observed…
We review simplified models in which a singlet Majorana dark matter candidate couples to Standard Model (SM) fermions through interactions mediated by scalar fermion partners. We summarize the two primary production mechanisms in these…