Investigators continue studying cosmic ray modulation throughout the heliosphere, using data from the Mount Washington neutron monitor and the IMP, voyager 1 and 2, and Pioneer 10 spacecrafts. They focus on 11-year and 22-year variations at 1 AU and 40 AU in the outer heliosphere, examining data from several energies and species of both anomalous and galactic cosmic rays. In one particularly puzzling aspect of anomalous cosmic ray data, these particles appear to completely vanish for two years around the changeover of solar magnetic polarity. The investigators are further studying temporal behavior of this anomalous component, as they believe effects in the outer heliosphere play a much greater role in overall solar modulation than previous theoretical studies suggest. In addition, they continue analyzing solar cosmic ray events, concentrating on whether or not protons interacting at the Sun and interplanetary protons in these events originate from the same particle population at the Sun, and studying rapid temporal variations in the energy spectra of interacting energetic solar protons in large flare events.
