Related papers: Study of positrons from cosmic rays interactions a…
It has been proposed that the excess in cosmic ray positrons at approximately 8 GeV, observed on both flights of the HEAT balloon experiment, may be associated with the annihilation of dark matter within the Milky Way halo. In this paper we…
The antimatter components measured in the Cosmic Ray (CR) flux are thought as secondary particles induced by the propagation of galactic CRs within the galaxy. Recent results from the PAMELA experiment show an unexpected increase of the…
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…
With experimental results of AMS on the spectra of cosmic ray (CR) $e^{-}$, $e^{+}$, $e^{-}+e^{+}$ and positron fraction, as well as new measurements of CR $e^{-}+e^{+}$ flux by HESS, one can better understand the CR lepton ($e^{-}$ and…
The space-borne antimatter experiment PAMELA has recently reported a surprising rise in the positron to electron ratio at high energies. It has also recently been found that electromagnetic radiative corrections in some cases may boost the…
This paper presents an introduction to the astrophysics of cosmic rays and diffuse gamma rays and discusses some of the puzzles that have emerged recently due to more precise data and improved propagation models: the excesses in Galactic…
Cosmic rays at the Earth include a secondary component originating in collisions of primary particles with the diffuse interstellar gas. The secondary cosmic rays are relatively rare but carry important information on the Galactic…
Here we briefly review possible indirect effects of dark matter (DM) of the Universe. It includes effects in cosmic rays (CR): first of all, the positron excess at $\sim$ 500 GeV and possible electron-positron excess at 1-1.5 TeV. We tell…
MeV dark matter (DM) particles annihilating or decaying to electron-positron pairs cannot, in principle, be observed via local cosmic-ray (CR) measurements because of the shielding solar magnetic field. In this letter, we take advantage of…
Recent advances in gamma-ray cosmic ray, infrared and radio astronomy have allowed us to develop a significantly better understanding of the galactic medium properties in the last few years. In this work using the DRAGON code, that…
The standard model of cosmic ray propagation has been very successful in explaining all kinds of the Galactic cosmic ray spectra. However, high precision measurement recently revealed the appreciable discrepancy between data and model…
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…
Several cosmic ray experiments have measured the positron fraction up to few hundred GeV. Their data have revealed an excess of positrons above 10 GeV that is not consistent with the secondary production of these particles in the…
Astrophysical and cosmological observations do not require the dark matter particles to be absolutely stable. If they are indeed unstable, their decay into positrons might occur at a sufficiently large rate to allow the indirect detection…
We use a diffusive model for the propagation of Galactic cosmic rays to estimate the charged pion production in interactions with protons of the interstellar medium. Cosmic ray nuclei from proton to iron are considered and the corresponding…
We use recently released data on the positron-to-electron ratio in cosmic rays from the AMS-02 experiment to constrain dark matter annihilation in the Milky Way. Due to the yet unexplained positron excess, limits are generally weaker than…
By solving the Fokker-Planck equation directly we examine effects of annihilation, particle escape and injection on the form of a steady-state positron distribution in thermal hydrogen plasmas with $kT<m_ec^2$. We show that the escape of…
High-energy cosmic ray electrons interaction with Dark Matter particles are considered. In particular, a weakening of energy spectrum of cosmic electrons is predicted resulting from inelastic electron scattering on hyper-pions in the…
The operation of AMS-02 opens a new era for the study of cosmic ray physics with unprecedentedly precise data which are comparable with the laboratory measurements. The high precision data allow a quantitative study on the cosmic ray…
We discuss challenges to a dark matter annihilation interpretation of the excess positron fraction in the cosmic rays observed by the PAMELA, Fermi-LAT and AMS-02 collaborations. The spectra of positrons from annihilations into the leptonic…