Related papers: Cosmic-Ray Positron Identification with the PAMELA…
We discuss the recently observed `excesses' in cosmic ray electron and positron fluxes which have been widely interpreted as signals of dark matter. By considering the production and acceleration of secondary electrons and positrons in…
Cosmic rays represent one of the most important energy transformation processes of the universe. They bring information about the surrounding universe, our galaxy, and very probably also the extragalactic space, at least at the highest…
We isolated the anomalous part of the cosmic electron-positron flux within a Bayesian likelihood analysis. Using 219 recent cosmic ray spectral data points, we inferred the values of selected cosmic ray propagation parameters. In the…
The AMS-02 has measured the cosmic ray electron (plus positron) spectrum up to ~TeV with an unprecedent precision. The spectrum can be well described by a power law without any obvious features above 10 GeV. The satellite instrument Dark…
The recent positron excess observed in the PAMELA satellite experiment strengthens previous experimental findings. We give here an analysis of this excess in the framework of the Stueckelberg extension of the standard model which includes…
The data collected by ATIC, PPB-BETS, FERMI-LAT and HESS all indicate that there is an electron/positron excess in the cosmic ray energy spectrum above $\sim$ 100 GeV, although different instrumental teams do not agree on the detailed…
Antimatter cosmic-rays are used to probe new phenomena in physics, including dark matter annihilation. We use the cosmic-ray positron fraction spectrum by the Alpha Magnetic Spectrometer, to search for such an annihilation signal in the…
A fundamental problem of cosmic ray (CR) physics is the determination of the average properties of Galactic CRs outside the Solar system. Starting from COS-B data in the 1980's, gamma-ray observations of molecular clouds in the Gould Belt…
This thesis discusses two different approaches for the measurement of cosmic-ray antiparticles in the GeV to TeV energy range. The first part of this thesis discusses the prospects of antiparticle flux measurements with the proposed PEBS…
We present a numerical simulation of cosmic ray transport in the heliosphere and show that AMS-02 should observe a decrease in the positron fraction above 40GeV compared to the fraction observed by PAMELA.
After the PAMELA finding of an increasing positron fraction above 10 GeV, the experimental evidence for the presence of a new electron and positron spectral component in the cosmic ray zoo has been recently confirmed by Fermi-LAT. We show…
We present a new measurement of the cosmic-ray positron fraction e+/(e+ + e-) obtained from the first balloon flight of the High Energy Antimatter Telescope (HEAT). Using a magnet spectrometer combined with a transition radiation detector,…
The search for cosmic ray anisotropy has been performed using particles collected by the Alpha Magnetic Spectrometer after the first five years of operation. The positron to electron ratio is consistent with isotropy at all energies and…
With the cosmic ray observations made by the Voyager 1 spacecraft outside the dominant modulating influence of the heliosphere, the comparison of computed galactic spectra with experimental data at lower energies is finally possible.…
Physics applications often involve large amounts of data and/or computing and often require secure resource sharing across organizational boundaries, and are thus not easily handled by today's Internet and Web infrastructures. Pamela (a…
The AMS-02 collaboration has just released its first result of the cosmic positron fraction $e^+/(e^-+e^+)$ with high precision up to $\sim 350$ GeV. The AMS-02 result shows the same trend with the previous PAMELA result, which requires…
CALET (CALorimetric Electron Telescope) is a high energy astroparticle physics experiment planned for a long exposure mission aboard the International Space Station (ISS) by the Japanese Aerospace Exploration Agency, in collaboration with…
The Alpha Magnetic Spectrometer (AMS), to be installed on the International Space Station, will provide data on cosmic radiations in a large energy range. The main physics goals in the astroparticle domain are the antimatter and the dark…
In recent years, a number of experiments have been conducted with the goal of studying cosmic rays at GeV to TeV energies. This is a particularly interesting regime from the perspective of indirect dark matter detection. To draw reliable…
The recent positron excess in cosmic rays (CR) observed by the PAMELA satellite may be a signal for dark matter (DM) annihilation. When these measurements are combined with those from FERMI on the total ($e^++e^-$) flux and from PAMELA…