Measurement of Ambient Neutrons in Correlation with Weather during July-August, 2017, in São José dos Campos, SP, Brazil
Inácio M. Martin *
Technological Institute of Aeronautics (ITA), SP, Brazil.
Franklin A. Silva
Technological Institute of Aeronautics (ITA), SP, Brazil.
Marcelo P. Gomes
Technological Institute of Aeronautics (ITA), SP, Brazil.
*Author to whom correspondence should be addressed.
Abstract
This work shows near-ground measurements of neutrons in the energy range of (0,03 eV to 10.0 MeV) performed at 1-minute intervals from July to August 2017. This monitoring was done in this period where there was dry weather in July and half of August. Between August 15th and the beginning of September, there were rains totaling 27 mm of intensity in the measurement region. Environmental neutrons measured at this energy range show a reasonable increase in their intensity in the rainy period. This observation is in agreement with the international project "COSMOS" whose objective is to show the increase of the intensity of neutron near the surface of the Earth with wet soil. With the use of a simple portable detector system for monitoring measurements, it was also possible to see the (day/night) variation in the region, formed by the presence of Rn-222 radon gas. The local presence of this gas emits particles α and β that hit the soil and air producing neutrons.
Keywords: Neutron measurements, weather, radon gas