Development of cosmic-ray snow gauge, (1)

A new type of snow gauge, in which the characteristics of cosmic-ray neutron absorption by snow are utilized, has been developed. From some experiments on the transition effect of neutrons in water and a tentative observation during the season of snowfall on Mt. Norikura, it is concluded that the water equivalent depth of snowcover can be estimated over a wide range from zero to a few meters in depth with an experimental accuracy of about a few percent of the depth. Various advantages obtained by means of the cosmic-ray snow gauge are emphasized in comparison with other types of snow gauges so far reported. (author)