A technique has been developed for calculating the electron-impact ionization single differential cross section directly from the integrated cross sections of positive-energy pseudostates occuring in close-coupling methods. Using the cross sections arising in the convergent close-coupling method, the approach is first tested against the existing benchmark theoretical and experimental data for electron scattering on hydrogen and helium. It is then applied to electron scattering on molecular hydrogen yielding excellent agreement with experimental data when normalized to the total ionization cross section.

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Positron-impact electronic excitation cross sections, mean excitation energies and mass stopping power of the H2 molecule have been calculated for energies from 10 eV up to 2 keV using the convergent close-coupling method that utilizes single and two-center expansions. Results are compared to previous studies. Application of Bragg's rule of stopping power additivity is discussed by comparing results obtained for atomic (H) and molecular (H2) targets for positron impact.

The satellite-borne PAMELA experiment has been continuously collecting data since 15th June 2006, when it was launched from the Baikonur cosmodrome to detect the charged component of cosmic rays over a wide energy range and with unprecedented statistics. The apparatus design is particularly suited for particle and antiparticle identification. The PAMELA experiment has measured the time variation of electron and positron spectrum at Earth in great detail, extending the measurement down to 70 MeV and 200 MeV respectively. The spectra have been evaluated with data collected from July 2006 to December 2009, i.e. during the A<0 solar minimum of solar cycle 23, over six-months intervals. These spectra provide important information for the study of CR propagation inside the heliosphere and the investigation of the charge-dependent solar modulation.

Positron scattering from the vibrational ground state of the hydrogen molecular ion has been investigated using the single-centre convergent close-coupling (CCC) method. Cross sections for dissociative excitation, dissociative ionisation, total inelastic scattering, and proton production have been calculated at incident positron energies from 10 to 500 eV. For this energy range the mass stopping power and mean excitation energy have also been calculated for both the positron and electron cases. Since there are no experiments or other calculations for positron scattering on the hydrogen molecular ion, the obtained results have been compared with corresponding CCC results for positron collisions with He+ and electron collisions with . Comparative analysis allows to estimate the quality of the approximations used in the present calculations.

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The first results from measuring the spectra of solar neutrons with energies of ~10–1000 MeV in the solar flares of 2006–2015 observed by the PAMELA international space experiment are presented. The PAMELA neutron detector with 3He counters and a moderator with an area of 0.18 m2 allows us to estimate the flux of solar neutrons during solar flares. Solar neutrons with energies of ~10–1000 MeV likely occurred in 21 out of the 24 analyzed flares of 2006–2015