Related papers: Electroweak lights from Dark Matter annihilations
The annihilation signal of particle dark matter can be strongly enhanced in over-dense regions such as close to the Galactic centre. We summarize some of our recent results on fluxes of gamma-rays, neutrinos and radio waves under different…
Arguably, the most popular candidate for Dark Matter (DM) is a massive, stable, Majorana fermion. However, annihilation of Majorana DM to two fermions features a helicity-suppressed s-wave rate. The process radiating a gauge boson via…
Arguably, the most popular candidate for Dark Matter (DM) is a massive, stable, Majorana fermion. However, annihilation of Majorana DM to two fermions often features a helicity-suppressed s-wave rate. Radiating a gauge boson via electroweak…
We study electroweak scale Dark Matter (DM) whose interactions with baryonic matter are mediated by a heavy anomalous $Z'$. We emphasize that when the DM is a Majorana particle, its low-velocity annihilations are dominated by loop…
Improved limits as well as tentative claims for dark matter annihilation into gamma-ray lines have been presented recently. We study the direct detection cross section induced from dark matter annihilation into two photons in a…
It is well known that the annihilation of Majorana dark matter into fermions is helicity suppressed. Here, we point out that the underlying mechanism is a subtle combination of two distinct effects, and we present a comprehensive analysis…
We investigate the effects of electroweak bremsstrahlung on bino-like neutralino dark matter pair annihilations in the minimal supersymmetric standard model (MSSM). We calculate the nonrelativistic pair annihilation cross sections via…
We consider a dark sector consisting of dark matter that is a Dirac fermion and a scalar mediator. This model has been extensively studied in the past. If the scalar couples to the dark matter in a parity conserving manner then dark matter…
In this paper, the electroweak phase transition, the gravitational waves and the dark matter issues are investigated in two scalar singlet extension of the standard model. The detectability of the gravitational wave signals are discussed by…
We discuss simple models which predict the existence of significant gamma-ray fluxes from dark matter annihilation. In this context the dark matter candidate is a Majorana fermion with velocity-suppressed tree-level annihilation into…
If dark matter particles pair annihilate into stable Standard Model particles, a population of energetic, non-thermal electrons and positrons is necessarily produced. The secondary radiation resulting from the energy losses of this…
In models of anapole dark matter (DM), the DM candidate is a Majorana fermion whose primary interaction with standard model (SM) particles is through an anapole coupling to off-shell photons. As such, at tree-level, anapole DM undergoes…
It has been recently shown that the electroweak baryogenesis mechanism is feasible in Standard Model extensions containing extra fermions with large Yukawa couplings. We show here that the lightest of these fermionic fields can naturally be…
Motivated by recent cosmic ray experimental results there has been a proposition for a scenario where a secluded dark matter particle annihilates, primarily, into Standard Model leptons through a low mass mediator particle. We consider…
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…
A strongly self-interacting component of asymmetric dark matter can collapse and form compact objects, provided there is an efficient mechanism of energy evacuation. If the dark matter quantum number is not completely conserved but it is…
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 study the effects of dark matter annihilation during and after the cosmic recombination epoch on the cosmic microwave background anisotropy, taking into account the detailed energy deposition of the annihilation products. It is found…
Weakly interacting massive particles provide a well-motivated framework for dark matter, naturally reproducing the observed relic abundance through thermal freeze-out. A recent claim of an indirect-detection signal from the Galactic halo,…
For Majorana dark matter, gauge boson bremsstrahlung plays an important role in enhancing an otherwise helicity-suppressed s-wave annihilation cross-section. This is well known for processes involving a radiated photon or gluon together…