相关论文: Positron Annihilation in the Milky Way and beyond
Electron-positron annihilation line from a Galactic center direction was discovered by the balloon-borne germanium gamma-ray telescope, and confirmed by OSSE experiment of CGRO mission. Extensive observations by INTEGRAL observatory permit…
Dark matter particles annihilating in the Galactic halo can provide a flux of positrons potentially observable in upcoming experiments, such as PAMELA and AMS-02. We discuss the spectral features which may be associated with dark matter…
We calculate the flux of high energy gamma-rays from annihilation of neutralino dark matter in the centre of the Milky Way and the three nearest dwarf spheroidals (Sagittarius, Draco and Canis Major), using realistic models of the dark…
The galactic 511 keV gamma-ray line has been observed since 1970's, and was identified as the result of electron-positron annihilation, but the origin of such positrons is still not clear. Apart from the astrophysical explanations, the…
PAMELA's observation that the cosmic ray positron fraction increases rapidly with energy implies the presence of primary sources of energetic electron-positron pairs. Of particular interest is the possibility that dark matter annihilations…
The positron fraction in cosmic rays was found to be steadily increasing in function of energy, above $\sim$10 GeV. This behaviour contradicts standard astrophysical mechanisms, in which positrons are secondary particles, produced in the…
The dwarf spheroidal satellite galaxies (dSphs) of the Milky Way are some of the most dark matter (DM) dominated objects known. We report on gamma-ray observations of Milky Way dSphs based on 6 years of Fermi Large Area Telescope data…
The mass to luminosity ratio of the dwarf satellite galaxies in the Milky Way suggests that these dwarf galaxies may contain substantial dark matter. The dark matter at the dense region such as within or at the vicinity of the centres of…
If annihilating MeV-scale dark matter particles are responsible for the observed 511 keV emission from the Galactic bulge, then new light gauge bosons which mediate the dark matter annihilations may have other observable consequences. In…
If the astronomical dark matter is made of weakly interacting, massive and stable species, it should annihilate on itself into particles. This process should produce rare antimatter cosmic rays and lead to distortions in their energy…
The nature of Dark Matter remains one of the outstanding questions of modern astrophysics. The success of the Cold Dark Matter cosmological model argues strongly in favor of a major component of the dark matter being in the form of…
We have made a calculation of the propagation of positrons from dark-matter particle annihilation in the Galactic halo for different models of the dark matter halo distribution using our 3D code. We show that the Green's functions are not…
The AMS-02 collaboration has recently presented measurements of excellent quality of the cosmic electron and positron fluxes as well as the positron fraction. We use the measurements of the positron flux to derive, for the first time,…
A possible hint of dark matter annihilation has been found in Cuoco, Korsmeier and Kr\"amer (2017) from an analysis of recent cosmic-ray antiproton data from AMS-02 and taking into account cosmic-ray propagation uncertainties by fitting at…
Gamma-ray searches for dark matter annihilation and decay in dwarf galaxies rely on an understanding of the dark matter density profiles of these systems. Conversely, uncertainties in these density profiles propagate into the derived…
The rotation curves of spiral galaxies are one of the basic predictions of the cold dark matter paradigm, and their shape in the innermost regions has been hotly debated over the last decades. The present work shows that dark matter…
Two different model-independent mapping techniques have been applied to OSSE, SMM, TGRS and balloon data and reveal a feature in the 0.511 MeV electron-positron annihilation radiation pattern of our galaxy centered roughly at l=-2 deg. and…
Most proposed dark matter candidates are stable and are produced thermally in the early Universe. However, there is also the possibility of unstable (but long-lived) dark matter, produced thermally or otherwise. We propose a strategy to…
For the SUSY 2007 conference, I was asked to review the topic of indirect searches for dark matter. As part of that talk, I summarized several observations which have been interpreted as the product of dark matter annihilations. In my…
The electron and positron cosmic rays observations have impulsed a hot debate regarding the origin of such particles. Their propagation in the galactic medium is modeled according to a successfully tested two--zone propagation model. The…