M. A. Mayorova

High-energy cosmic antiparticle excess vs. isotropic gamma-ray background problem in decaying dark matter Universe

We are going to show that any conventional decaying dark matter model, providing an explanation of cosmic antiparticle excess observed by PAMELA and AMS-02, inevitably faces the contradiction with isotropic diffuse gamma-ray background, measured by FERMI/LAT.

Time variations of proton flux in Earth inner radiation belt during 23/24 solar cycles based on the PAMELA and the ARINA data

The PAMELA and the ARINA experiments are carried out on the board of satellite RESURS-DK1 since 2006 up to now. Main goal of the PAMELA instrument is measurements of high energy antiparticles in co ...

Review of the results of measurements of the fluxes of the charged components of galactic cosmic rays in the experiments PAMELA and AMS-02

The paper provides a review of the results of precision measurements of the fluxes of different charged components of galactic cosmic rays (positrons and antiprotons, protons and helium nuclei) in modern experiments with magnetic spectrometers PAMELA and AMS-02, operating successfully for a few years (since 2006 and 2011, respectively) in Earth orbit. A priority of the PAMELA spectrometer scientific discoveries is noted. It is also noted that the measurements from the AMS-02 experiment are of high statistical accuracy and have reliably confirmed previous data, having been able to advance to a higher energy range.

Analysis of a possible explanation of the positron anomaly in terms of dark matter

The possibility of explaining the positron anomaly on the basis of models involving the darkmatter annihilation or decay is being widely discussed at the present time. However, such models are severely constrained by data on cosmic gamma radiation. Two different procedures that rely on the χ2 criterion and which permit taking this constraint into account are considered in the present study. In one case, the use of positron data alone in searches for a minimum value of χ2 via varying model parameters is followed by a comparison with gamma-radiation data. In the second case, the χ2 functional is minimized by simultaneously employing positron and gamma-radiation data, whereby a more lenient (more “flexible”) constraint is obtained. Nevertheless, either procedure rules out the possibility of explaining the positron anomaly in terms of unstable dark matter distributed over the whole halo. The assumption that the dark-matter component undergoing annihilation (decay) is concentrated within the galactic disk makes it possible to remove the constraint in either case.

Spatial distribution of high-energy protons in the inner radiation belt, according to data from the ARINA and VSPLESK satellite experiments

Measurements of high-energy proton fluxes (30–100 MeV) by the low-orbit satellite experiments ARINA (Resurs-DK1 satellite; inclination, ~70°; altitude, ~600 km; 2006–2016) and VSPLESK (International Space Station (ISS); inclination, ~52°; altitude, ~400 km; 2008–2013) are considered. The spectrometers have the same physical layouts, 10% energy resolution, and 7° angular resolution. Proton fluxes of different energies in the inner radiation belt (L < 2.0) are analyzed. The period of observation covers the declining phase of the 23rd solar cycle and the main part of the 24th cycle. The distribution of fluxes is analyzed for different proton energies, L-shells, and geomagnetic field inductions. It is shown that depending on the L-shell, proton fluxes can grow by up to 7 times (L = 1.16) during the Solar minimum, compared to the Solar maximum.

Evaluation of the Antiproton Flux from the Antineutrino Electron Scattering

Recent experiments in high enegry cosmic ray physics, PAMELA and AMS-02, excite a new interest to the mechanisms of generation of galactic antiparticles. In spite of the fact that global picture coincides with the predictions of the standard model, there are some black spots stimulating scientists to involve into research a particularly new physics like dark matter. In the present work, we make an attempt to estimate the impact of standard neutrino processes into the total flux of secondary antiprotons detected by contemporary experiments.