相关论文: Gamma-ray lines and One-Loop Continuum from s-chan…

Lines in the energy spectrum of gamma rays are a fascinating experimental signal, which are often considered "smoking gun" evidence of dark matter annihilation. The current generation of gamma ray observatories are currently closing in on…

We study the spectra of gamma ray signals that arise from dark matter annihilation in the universe. We focus on the large class of theories where the photon spectrum includes both continuum spectrum of gamma rays that arise from…

Monochromatic photons could be produced in the annihilation or decay of dark matter particles. At high energies, the search for such line features in the cosmic gamma-ray spectrum is essentially background free because plausible…

The observation of a gamma-ray line in the cosmic-ray fluxes would be a smoking-gun signature for dark matter annihilation or decay in the Universe. We present an improved search for such signatures in the data of the Fermi Large Area…

Dark matter may interact with Standard Model (SM) particle through the exchange of a massive spin-2 graviton producing signals that can be detected. In this work we examine the $\gamma$-ray emission signals, including the line emission and…

In dark matter (DM) models, the production of a gamma line (or of a "box-shaped" gamma-ray spectrum) from DM annihilation proceeds in general from a loop diagram involving a heavy charged particle. If the charged particle in the loop…

We discuss the visibility of gamma lines from dark matter annihilation. We point out a class of theories for dark matter which predict the existence of gamma lines with striking features. In these theories, the final state radiation…

Gamma-ray lines from dark matter annihilation ($\chi\chi\to \gamma X$, where $X=\gamma,h,Z$) are always accompanied, at lower energies, by a continuum gamma-ray spectrum stemming both from radiative corrections ($X=\gamma$) and from the…

Monoenergetic $\gamma$-ray spectral lines are among the cleanest signatures of dark matter annihilation. We analyze 15 years of Fermi-LAT data, find no spectral lines, and place strong constraints on dark matter annihilation to…

Recent reports of a gamma-ray line feature at ~130 GeV in data from the Fermi Gamma-Ray Space Telescope have generated a great deal of interest in models in which dark matter particles annihilate with a sizable cross section to final states…

A commonly encountered obstacle in indirect searches for galactic dark matter is how to disentangle possible signals from astrophysical backgrounds. Given that such signals are most likely subdominant, the search for pronounced spectral…

Decaying or annihilating dark matter particles could be detected through gamma-ray emission from the species they decay or annihilate into. This is usually done by modelling the flux from specific dark matter-rich objects such as the Milky…

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…

Dark matter constitutes one of the most intriguing but so far unresolved issues in physics today. In many extensions of the Standard Model the existence of a stable Weakly Interacting Massive Particle (WIMP) is predicted. The WIMP is an…

Dark matter particle annihilation or decay can produce monochromatic gamma-ray lines and contribute to the diffuse gamma-ray background. Flux upper limits are presented for gamma-ray spectral lines from 7 to 200 GeV and for the diffuse…

Indications for a gamma-ray line(s) signal towards the Galactic center at an energy of about 130 GeV have been recently presented. While dark matter annihilations are a viable candidate for this signal, it is generally expected that such a…

Recently, it has been shown that electrons and positrons from dark matter (DM) annihilations provide an excellent fit to the Fermi, PAMELA, and HESS data. Using this DM model, which requires an enhancement of the annihilation cross section…

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…

We suggest a dark matter scenario which could contribute the possible anomaly observed by Fermi-LAT $\gamma$-ray space telescope. It is based on the model recently proposed by Weinberg. In our scenario the gamma-ray line signal comes from…

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…