Related papers: The 'PAMELA anomaly' indicates a nearby cosmic ray…
We calculate the diffuse intensity of cosmic ray (CR) nuclei and their secondaries in the Boron-Carbon group produced by supernova remnants (SNR). The trajectories of charged particles in the SNR are modeled as a random walk in the test…
An extended seesaw model proposed to achieve low scale leptogenesis can resolve the excess positron and electron fluxes observed from PAMELA, ATIC and/or Fermi-LAT, and simultaneously accommodate some of recent experimental results for dark…
The large intensity of greater than 10 GeV positrons which apparently come from sources outside the Earth-Sun system observed recently by many spacecraft (PAMELA, FERMI, AMS2) is still a mystery with broad implications. In our attempts to…
Protons and helium nuclei are the most abundant components of the cosmic radiation. Precise measurements of their fluxes are needed to understand the acceleration and subsequent propagation of cosmic rays in the Galaxy. We report precision…
We studied the variation of $e^+$ and $\bar p$ top of the atmosphere spectra due to the parameters uncertainties of the Milky Way geometry, propagation models and cross sections. We used the B/C data and Galprop code for the propagation…
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…
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…
A number of papers attempt to explain the positron anomaly in cosmic rays, observed by PAMELA and AMS-02, in terms of dark matter (DM) decays or annihilations. However, the recent progress in cosmic gamma-ray studies challenges these…
We explain the PAMELA positron excess and the PPB-BETS/ATIC e+ + e- data using a simple two component dark matter model (2DM). The two particle species in the dark matter sector are assumed to be in thermal equilibrium in the early…
Recently, new data on antiprotons and positrons from PAMELA, e- + e+ spectra from ATIC, FERMI and HESS up to TeV energies all indicate deviations from expectations, which has caused an interesting mix of new explanations, ranging from…
Precision measurements of the electron component in the cosmic radiation provide important information about the origin and propagation of cosmic rays in the Galaxy. Here we present new results regarding negatively charged electrons between…
Recent precision measurements of the flux of cosmic ray positrons by the Alpha Magnetic Spectrometer show that the spectrum has a marked softening feature for energies close to one TeV. A possible interpretation of this result is that the…
The satellite-borne experiment PAMELA has been used to make a new measurement of the cosmic-ray antiproton flux and the antiproton-to-proton flux ratio which extends previously published measurements down to 60 MeV and up to 180 GeV in…
We propose to test the dark matter (DM) interpretation of the positron excess observed by the PAMELA cosmic-ray (CR) detector through the identification of a Galactic diffuse gamma-ray component associated to DM-induced prompt and radiative…
In continuation of their earlier measurements, the PAMELA group reported data on antiproton flux and $\bar{P}/P$ ratios in 2010 at much higher energies. In past we had dealt with these specific aspects of PAMELA data in great detail and…
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…
If dark matter (DM) annihilation accounts for the tantalizing excess of cosmic ray electron/positrons, as reported by the PAMELA, ATIC, HESS and FERMI observatories, then the implied annihilation cross section must be relatively large. This…
We present a scenario where dark matter is in the form of dark atoms that can accomodate the experimentally observed excess of positrons in PAMELA and AMS-02 while being compatible with the constraints imposed on the gamma-ray flux from…
Recent results from the PAMELA experiment indicate an excess in the positron spectrum above 10 GeV, but anti-proton data are consistent with the expected astrophysical backgrounds. We propose a scenario that reproduces these features. Dark…
The PAMELA satellite experiment has measured the cosmic-ray positron fraction between 1.5 GeV and 100 GeV. The need to reliably discriminate between the positron signal and proton background has required the development of an ad hoc…