相关论文: Gamma Lines from the Hidden Sector
We present a simple model of weak-scale thermal dark matter that gives rise to X-ray lines. Dark matter consists of two nearly degenerate states near the weak scale, which are populated thermally in the early universe via co-annihilation…
Weakly interacting massive particles, as a major candidate of dark matter (DM), may directly annihilate or decay into high-energy photons, producing monochromatic spectral lines in the gamma-ray band. These spectral lines, if detected, are…
If the dark matter is part of a hidden sector with only very feeble couplings to the Standard Model, the lightest particle in the hidden sector will generically be long-lived and could come to dominate the energy density of the universe…
Dark matter annihilation in Galactic substructure produces diffuse gamma-ray emission of remarkably constant intensity across the sky, and in general this signal dominates over the smooth halo signal at angles greater than a few tens of…
Annihilation of cosmologically distributed dark matter is predicted to produce a potentially observable flux of high energy photons. Neglecting the contribution from local structure, this signal is predicted to be virtually uniform on the…
In this review article the current status of particle dark matter is addressed. We discuss the main theoretical extensions of the standard model which allow to explain dark matter in terms of a (yet undiscovered) elementary particle. We…
The nature of dark matter remains one of the greatest unsolved mysteries in elementary particle physics. It might well be that the dark matter particle belongs to a dark sector completely secluded or extremely weakly coupled to the visible…
Although well established observations on cosmological, cluster, and galactic scales strongly suggest the existence of dark matter (DM), our understanding of its non-gravitational properties is still lacking. I review basic aspects of…
Using 14 years of Fermi-LAT data and 10 years of H.E.S.S. observations in the direction of the galactic center, we derive limits on gamma-ray lines originated from dark matter annihilations for fermionic and scalar fields. We describe the…
Cosmologically long-lived, composite states arise as natural dark matter candidates in theories with a strongly interacting hidden sector at a scale of 10 - 100 TeV. Light axion-like states, with masses in the 1 MeV - 10 GeV range, are also…
Using 43 months of public gamma-ray data from the Fermi Large Area Telescope, we find in regions close to the Galactic center at energies of 130 GeV a 4.6 sigma excess that is not inconsistent with a gamma-ray line from dark matter…
The detection of non-baryonic dark matter through its gamma-ray annihilation in the centre of our galaxy has been studied. The gamma fluxes according to different models have been simulated and compared to those expected to be observed with…
A number of signals involving charged cosmic rays and high-energy photons have been interpreted as being due to annihilating dark matter. This article provides an overview of the experimental evidence and discusses in particular detections…
Scenarios with hidden, spontaneously broken, non-abelian gauge groups contain a natural dark matter candidate, the hidden vector, whose longevity is due to an accidental custodial symmetry in the renormalizable Lagrangian. Nevertheless,…
Coy dark matter is an effective scheme in which a fermionic dark matter candidate interacts with the Standard Model fermions via a pseudoscalar mediator. This simple setup avoids the strong constraints posed by direct detection experiments…
We study the consequences of an extension of the standard model containing an invisible extra gauge group under which the SM particles are neutral. We show that effective operators, generated by loops of heavy chiral fermions charged under…
The extremely large hierarchy observed in the fermion mass spectrum remains as one of the most puzzling and unresolved issues in particle physics. In a recent proposal, however, it was demonstrated that by introducing one Higgs doublet (or…
Satellite galaxies of the Milky Way are among the most promising targets for dark matter searches in gamma rays. We present a search for dark matter consisting of weakly interacting massive particles, applying a joint likelihood analysis to…
Individual extragalactic dark matter halos, such as those associated with nearby galaxies and galaxy clusters, are promising targets for searches for gamma-rays from dark matter annihilation. We review the predictions for the annihilation…
Automated tools for the computation of amplitudes and cross sections have become the backbone of phenomenological studies beyond the standard model. We present the latest developments in MadDM, a calculator of dark-matter observables based…