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Open AccessJournal ArticleDOI

Cosmic-Ray Positron Energy Spectrum Measured by PAMELA

TLDR
The satellite-borne experiment PAMELA has been used to make a new measurement of the cosmic-ray positron flux and fraction that extends previously published measurements up to 300 GeV in kinetic energy.
Abstract
Precision measurements of the positron component in the cosmic radiation provide important information about the propagation of cosmic rays and the nature of particle sources in our Galaxy. The satellite-borne experiment PAMELA has been used to make a new measurement of the cosmic-ray positron flux and fraction that extends previously published measurements up to 300 GeV in kinetic energy. The combined measurements of the cosmic-ray positron energy spectrum and fraction provide a unique tool to constrain interpretation models. During the recent solar minimum activity period from July 2006 to December 2009, approximately 24 500 positrons were observed. The results cannot be easily reconciled with purely secondary production, and additional sources of either astrophysical or exotic origin may be required.

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Journal ArticleDOI

Dark Matter "Transporting" Mechanism Explaining Positron Excesses.

TL;DR: In this article, the authors proposed a novel mechanism to explain the positron excesses, which are observed by satellite-based telescopes including PAMELA and AMS-02, in dark matter (DM) scenarios.
Journal ArticleDOI

New calculation of antiproton production by cosmic ray protons and nuclei

TL;DR: This work calculates antiproton production in pp-, pA-, and AA-interactions using EPOS-LHC and QGSJET-II-04, two of the most advanced Monte Carlo (MC) generators tuned to numerous accelerator data including those from the Large Hadron Collider.
Journal ArticleDOI

Loopy Constraints on Leptophilic Dark Matter and Internal Bremsstrahlung

TL;DR: In this paper, the authors derived complementary constraints on internal bremsstrahlung in DM annihilation using LEP mono-photon data, measurements of the anomalous magnetic moments of the electron and the muon, and searches for lepton flavor violation.
Journal ArticleDOI

A new look at the cosmic ray positron fraction

TL;DR: In this paper, a semi-analytic two-zone model was used to model the positron flux generated by dark matter species in the Galaxy. But it was found that the mass of the dark matter candidates is always larger than 500 GeV.
Journal ArticleDOI

Solar Modulation of the Proton Local Interstellar Spectrum with AMS-02, Voyager 1 and PAMELA

TL;DR: In this paper, a modified version of the force-field approximation with an energy-dependent modulation parameter is introduced, yielding better results on proton data than the forcefield approximation.
References
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