Related papers: Absolute electron and positron fluxes from PAMELA/…
A new measurement of the cosmic ray antiproton-to-proton flux ratio between 1 and 100 GeV is presented. The results were obtained with the PAMELA experiment, which was launched into low-earth orbit on-board the Resurs-DK1 satellite on June…
The positron fraction observed by PAMELA and other experiments up to ~ 100 GeV is analyzed in terms of models of cosmic-ray propagation. It is shown that generically we expect the positron fraction to reach ~ 0.6 at energies of several TeV,…
The AMS experiment onboard the International Space Station has recently provided cosmic ray electron and positron data with unprecedented precision in the range from 0.5 to 350 GeV. The observed rise in the positron fraction at energies…
It is commonly assumed that dark matter may be composed of one or at most a few elementary particles. PAMELA data present a window of opportunity into a possible relationship between luminous and dark matter. Along with ATIC data the two…
In the positron-electron annihilation process, finite deviations from the standard calculation based on the Fermi's Golden rule are suggested in recent theoretical work. This paper describes an experimental test of the predictions of this…
The recent observation by the PAMELA satellite of a rising positron fraction up to $\sim$ 100 GeV has triggered a considerable amount of putative interpretations in terms of dark matter (DM) annihilation or decay. Here, we make a critical…
The recent data from PAMELA and Fermi-LAT can be interpreted as evidence of new astrophysical sources of high energy positrons. In that case, such astrophysical positrons constitute an additional background against the positrons from dark…
Very recently, PAMELA Collaboration has formally reported two sets of data on positron and antiproton flux measurements done at very high energies and with unprecedented accuracy. The reports reveal a puzzle of great topical interest and…
Recent cosmic ray, gamma ray, and microwave signals observed by Fermi, PAMELA, and WMAP indicate an unexpected primary source of e+e- at 10-1000 GeV. We fit these data to "standard backgrounds" plus a new source, assumed to be a separable…
We present a precise measurement of the combined electron plus positron flux from 0.5 GeV to 1 TeV, based on the analysis of the data collected by the Alpha Magnetic Spectrometer during the first 30 months of operations aboard the…
This thesis presents an analysis of the cosmic-ray electron and positron flux using the AMS-02 detector on the International Space Station as a function of time and energy. The time-averaged flux is integrated over 6.5 years of AMS-02…
Recently, a tentative 130 GeV $\gamma$-ray line signal was identified by quite a few groups. If correct it would constitute a ``smoking gun'' for dark matter annihilations. Interestingly, the spectra of the cosmic ray electrons detected by…
The positron excess observed by the PAMELA experiment may come from dark matter annihilation, if the annihilation cross section is large enough. We show that the dark matter annihilation scenarios to explain the positron excess may also be…
Positrons are known to be produced in interactions between cosmic-ray nuclei and interstellar matter ("secondary production"). Positrons may, however, also be created by dark matter particle annihilations in the galactic halo or in the…
The flux of positrons and electrons ($e^+ + e^-$) has been measured by the $Fermi$ Large Area Telescope (LAT) in the energy range between 7 GeV and 2 TeV. We discuss a number of interpretations of Pass 8 $Fermi$-LAT $e^+ + e^-$ spectrum,…
We present a critical analysis of the observational constraints on, and of the theoretical modeling of, aspects of cosmic ray (CR) generation and propagation in the Galaxy, which are relevant for the interpretation of recent positron and…
The precise measurements of energy spectra of cosmic ray positrons and/or electrons by recent experiments show clear excesses above 10 GeV. Moreover, a potential sharp spectral feature was suggested by the Dark Matter Particle Explorer…
Recent preliminary results from the PAMELA experiment indicate the presence of an excess of cosmic ray positrons above 10 GeV. In this letter, we consider possibility that this signal is the result of dark matter annihilations taking place…
The Fermi Large Area Telescope (LAT) has provided the measurement of the high energy cosmic ray electrons plus positrons (CRE) spectrum with unprecedented accuracy form 20 GeV to 1 TeV. Recently this range has been extended down to ~ 7 GeV.…
Reliable data from the very recent high-precision measurements on the antiproton fluxes and the antiproton-to-proton ratios by the PAMELA Collaboration at relatively much higher energies are now available. The results with regard to…