The spectrum of cosmic ray neutrons at sea level in the range 0.4-1.2 GeV

The neutron spectrum at sea level has been measured in the kinetic energy range 0.4-1.2 GeV using the charge exchange reaction n+p to p+n. In this energy range the vertical intensity of neutrons is found to be consistent with the value calculated from the work of Hughes and Marsden (abstr. A19942 of 1966) who estimated the global spectrum of neutrons from indirect measurements of the multiplicity distribution of neutrons in a neutron monitor.