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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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Ultra-relativistic nonthermal power-law ensembles: Cosmic-ray electrons and positron fraction

TL;DR: In this paper, the probability density of power-law ensembles in phase space is derived, as well as an extensive entropy functional, and the phase-space measure is transformed into a spectral number density, parameterized with the Lorentz factor of the charges and quantized in Fermi statistics.
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A next-generation liquid xenon observatory for dark matter and neutrino physics

- 22 Dec 2022 - 
TL;DR: The dual-phase Xenon time-projection chamber is the leading technology to cover the available parameter space for weakly interacting massive particles, while featuring extensive sensitivity to many alternative dark matter candidates as mentioned in this paper .
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Common origin of the high energy astronomical gamma rays, neutrinos and cosmic ray positrons?

TL;DR: In this article, the observed fluxes, spectra and sky distributions of the high energy astronomical neutrinos, gamma rays and cosmic ray positrons satisfy the simple relations expected from their common production in hadronic collisions in/near source of high energy cosmic rays with diffuse matter.
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Removing the conspiracy of BSM physics and BSM cosmology

TL;DR: The standard model (SM) of elementary particles finds no contradictions in the experimental data, but appeals to extensions for solutions of its internal problems and physical basis of the modern c... as discussed by the authors.
References
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