Distribution of neutrons near the Earth’s surface

Abstract. The distribution of the count rate of neutrons (per second) near the Earth’s surface for two directions: towards the Earth and away from it, is studied using the experimental data, obtained in Moscow during 1996. The analysis shows that the mathematical approximation of the neutron count rate distribution can be described by a sum of two functions: a Poison distribution and a log-normal distribution. This is in agreement with the two known sources of the total neutron flux near the Earth’s surface: generation of neutrons in nuclear interactions of high-energy cosmic ray particles with the Earth’s atmosphere and neutron production in the Earth’s crust. The log-normal distribution describes the contribution of the Earth’s crust to the total neutron flux near the Earth. Therefore, these dynamic processes in the Earth’s crust change the parameters of the log-normal distribution.