相关论文: Bounds on Long-Lived Relics from Diffuse Gamma Ray…
Nearby clusters and groups of galaxies are potentially bright sources of high-energy gamma-ray emission resulting from the pair-annihilation of dark matter particles. However, no significant gamma-ray emission has been detected so far from…
The excess above 1 GeV in the energy spectrum of the diffuse Galactic gamma radiation, measured with the EGRET experiment, can be interpreted as the annihilation of Dark Matter (DM) particles. The DM is distributed in a halo around the…
We study the cross-correlation between maps of the unresolved $\gamma$-ray background constructed from the 12-year data release of the Fermi Large-Area Telescope, and the overdensity of galaxies in the redshift range $z\lesssim0.4$ as…
A series of experiments measuring high-energy cosmic rays have recently reported strong indications for the existence of an excess of high-energy electrons and positrons. If interpreted in terms of the decay of dark matter particles, the…
Dark matter particles from the Galactic halo can be gravitationally trapped in the solar core or in external orbits. The enhanced density of dark matter particles either in the solar core or in external orbits can result in the annihilation…
The observed anomalous excess of high-energy cosmic ray (CR) positrons is widely discussed as possible indirect evidence for dark matter (DM). However, any source of cosmic positrons is inevitably the source of gamma radiation. The least…
The possibility to use $\gamma$--ray data from the Galactic Center (GC) to constrain the cosmological evolution of the Universe in a phase prior to primordial nucleosyntesis, namely around the time of cold dark matter (CDM) decoupling, is…
Data from four Fermi-detected gamma-ray bursts (GRBs) is used to set limits on spectral dispersion of electromagnetic radiation across the universe. The analysis focuses on photons recorded above 1 GeV for Fermi detected GRB 080916C, GRB…
Dwarf spheroidal galaxies compose one of the most dark matter dominated classes of objects, making them a set of targets to search for signals of dark matter annihilation. Recent developments in gamma-ray astronomy, most importantly the…
We search data from the Energetic Gamma Ray Experiment Telescope (EGRET) for a gamma-ray line in the energy range 0.1-10 GeV from the 10 X 10 degree region around the Galactic center. Our null results lead to upper limits to the line flux…
Dark matter captured by interaction with electrons inside the Sun may annihilate via long-lived mediator to produce observable gamma ray signals. We utilize solar gamma ray flux measurements from the Fermi Large Area Telescope and High…
We investigate the modifications to predictions for the abundances of light elements from standard Big-Bang nucleosynthesis when exotic late-decaying particles with lifetimes exceeding ~1 sec are prominent in the early Universe. Utilising a…
Existing limits on the non-radiative decay of one neutrino to another plus a massless particle (e.g., a singlet Majoron) are very weak. The best limits on the lifetime to mass ratio come from solar neutrino observations, and are $\tau/m…
We use measurements of the intergalactic medium (IGM) temperature from the Lyman-$\alpha$ forest to place new limits on models in which long-lived dark sector (DS) particles, with lifetimes longer than $10^{16}$ s, deposit energy into the…
The gamma-ray line from dark matter (DM) annihilation is too weak to observe, but its observation will uncover much information, e.g., the DM mass and an nomalously large annihilation rate $\sim0.1$ pb into di-photon. In this work, we…
Dark Matter is essential for structure formation in the late Universe so it must be stable on cosmological time scales. But how stable exactly? Only assuming decays into relativistic particles, we report an otherwise model independent bound…
The DArk Matter Particle Explorer (DAMPE) is well suitable for searching for monochromatic and sharp $\gamma$-ray structures in the GeV$-$TeV range thanks to its unprecedented high energy resolution. In this work, we search for $\gamma$-ray…
The EGRET excess in the diffuse galactic gamma ray data above 1 GeV shows all the features expected from Dark Matter WIMP Annihilation: a)it is present and has the same spectrum in all sky directions, not just in the galactic plane. b) The…
If dark matter decays or annihilates into electrons and positrons, it can affect radiation and cosmic-ray backgrounds. We review a novel, more general analysis of constraints on decaying dark matter models, by introducing the response…
We consider an extension of the Standard Model by a singlet scalar that accounts for the dark matter of the Universe. Within this model we compute the expected gamma ray flux from the annihilation of dark matter particles in a consistent…