Cosmic-Ray Neutrons


The cosmic-ray neutron (CRN) method is a novel technique that utilises the naturally occurring cosmogenic neutrons (neutrons generated through cosmic ray interaction with the atmosphere) as a neutron source. Therefore it is considered a passive technique based on the non invasive measurement of the thermalised neutrons that are moderated and back scattered out of the soil.


This technique has been employed for the measurement of soil moisture [1].


Since the method relies on a natural neutron source, low counts are obtained and significant integration time is required.

Development Status




1. Zreda, M., Desilets, D., Ferre, T. P. A. & Scott, R. L. (2008) Measuring soil moisture content non-invasively at intermediate spatial scale using cosmic-ray neutrons. Geophysical Research Letters, 35.