A Study on Nuclear-Active Component in Extensive Air Showers at Mountain Altitude

Abstract

Nuclear-active component ( N -component) in extensive air shower was observed by means of a large multiplate cloud chamber and two standard neutron monitors which were installed in EAS array consisting of 16 density detectors. High energy N -particles above 10 Gev were observed by the multiplate cloud chamber, while N -particles of energy larger than 200 Mev were observed by the neutron monitor separately. The integral energy spectra of N-particles are shown to be represented by E -0.7±0.1 , E -1.1±0.2 and E -1.5±0.2 for the events observed at distances 0–5 m, 5–10 m and more than 10 m, respectively, from shower axis. And the integral energy spectrum of total N -particles is expressed by E -1.0±0.1 . The lateral distribution of N -particles above 10 Gev is obtained as r -1.4±0.2 with in 25 m from the axis. The lateral distribution of low energy N -particles is expressed by r -1.0±0.2 for the distance 5–30 m and the distribution becomes flatter within 5 m. These lateral distribution of each energy region c...