The influence of background radiation on the events registered in a neutron monitor at mountain heights

Abstract

We have made an experimental check of an influence caused by external background of slow thermal neutrons on the temporal distribution of the signals from the standard NM64 supermonitor used as a detector of hadron component of extensive air showers with the energy above 1015 eV. Special attention in our study was paid to the possible connection of this background with the anomalously (up to a few milliseconds) delayed signals from the neutron monitor which were detected when the shower cores passed in its close vicinity. It has been found that in spite of the long, up to tens of milliseconds, presence of thermal neutrons nearby the shower axis, these external neutrons do not have any effect on the temporal behaviour of the neutrons diffusing inside the monitor as well as on the distribution of gamma-radiation accompanying the absorption of the latter.

Remarks on recent results on neutron production during thunderstorms

“…A product of the registration efficiency and the total area of six helium counters is 0:45 m 2 [15]. Accordingly, we readily obtain the flux of thermal neutrons for six considered neutron events: 3462, 1600, 1684, 4567, 3717, and 2722 neutrons per m 2 per minute.…”

High energy cosmic rays and thunderstorm connected radiations at the Tien Shan complex installation

“…The program of scientific investigation which is currently realized here anticipates the activity in a wide range of problems connected with both physics of cosmic rays and with applied geophysics. Hence, the astroparticle group of experiments which is based on using the newly built extensive air shower (EAS) installation [1] involves the following directions of scientific research:…”

Strong variations of gamma-ray and atmospheric electric field during various meteorological conditions by observations in Yakutsk and Tiksi

“…Numerous studies of recent decades describe in detail the results of studies of variations in the surface gamma background. Strong variations of the gamma background during intense precipitation [1] and in a thunderstorm atmosphere [2] have been repeatedly noted. There is still no single point of view on the mechanism of such variations of the gamma background.…”