Geomagnetic-Cutoff Distribution Functions for Use in Estimating Detector Response to Neutrinos of Atmospheric Origin

A procedure has been developed for deriving functions which characterize the effect of geomagnetic cutoffs on the charged primary cosmic rays that give rise to neutrinos arriving in any given direction at specified points on or in the earth. These cutoff distribution functions, for use in atmospheric-neutrino flux calculations, have been determined for eight nucleon-decay-experiment sites, by use of a technique which employs the Stormer cutoff expression, and which assumes collinear motion of neutrino and parent primary.