The Neutron Flux Variation in the Earth’s Atmosphere Depending on the Solar Proton Flux

Marina Poje, Branko Vuković, Maja Varga Pajtler, Vanja Radolić, Igor Miklavčić, Josip Planinić

Department of Physics, University of Osijek, Osijek, Croatia.

DOI: 10.4236/acs.2013.34050                

Abstract

The Earth is continually exposed to the cosmic radiation of both solar and galactic origin. Solar eruption and solar ac- tivity may affect cosmic radiation flux density which has a secondary effect on the flux of particles in the atmosphere as well. Such one event was recorded in the last week of October 2003, where the measured dose rate of the cosmic radia- tion in the aircraft ATR 42 was 1.8 times higher than the average value of the other measurements. Later we found the data on an unusual solar activity in the mentioned time interval. Analysis of the increasing solar proton flux during the solar flare, as well as the decreasing neutron flux in the atmosphere (representing the galactic radiation), on May 14 and 15, 2005, showed a nonlinear correlation with the exponential equation of regression; this one described galactic ray modulation by solar flux during the short term variation of cosmic radiation.

Keywords

Cosmic Radiation; Solar Radiation; Galactic Component; Forbush’s Decrease

Conflicts of Interest

The authors declare no conflicts of interest.

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