Latitude survey of neutron multiplicity using a shipborne NM-64 neutron monitor

• Published in: Canadian Journal of Physics
• Main Authors: Kodama, M., Ohuchi, T.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1968
• Subjects: General Physics and Astronomy; Antarctic; Antarc*
• Online Access: http://dx.doi.org/10.1139/p68-425; http://www.nrcresearchpress.com/doi/pdf/10.1139/p68-425

The latitude dependence of the neutron multiplicity effect has been measured using a 3-NM-64 neutron monitor along the route Japan–Australia–Antarctic–South Africa–Ceylon–Japan between December 1966 and April 1967. Throughout the whole voyage, events whose multiplicities were in the range 1 to 6 and more were recorded. A preliminary report of the threshold-rigidity dependence of events of various multiplicities is presented, based on data from the outward voyage. The gradient of the rigidity dependence is found to be steepest for events of multiplicity 2, while that for multiplicity 1 is almost the same as that for multiplicity 3. The mean multiplicity of events recorded by the present shipborne neutron monitor varies linearly from 1.418 to 1.445 in the rigidity interval 0.1–17 GV.