Neutrons of terrestrial origin and the endogenous activity of the Earth

Abstract

As a result of ground measurements of a) thermal and fast neutrons, carried out at the Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation of the Russian Academy of Sciences (IZMIRAN), Moscow; b)~thermal neutrons, carried out at the Karymshina Complex Geophysical Observatory, Kamchatka Branch, Geophysical Survey, Russian Academy of Sciences, near Petropavlovsk-Kamchatsky in 2010--2012, neutron fluxes were registered, related to earthquakes in Chile, Japan, Indonesia. The magnitude of these earthquakes was $M = 8.6 9$. Fluxes of neutrons were also registered during the volcanic eruption in Iceland in 2010. In 2013--2015 bursts of neutron fluxes were registered, not only by the instrumental complex with helium counters, i.e. with an energy of several MeV, but also by neutron monitors with threshold energy of 20--30~MeV. We can assume that the emergence of neutrons on the surface of the Earth is related to nuclear reactions in the Earth's interior, generating a variety of particles with high penetrating capacity.