Thermal neutrons' response to the GLEs

The paper presents the observations of the thermal neutrons flux during the Ground level enhancements (GLEs) recorded on January 20, 2005 and December 13, 2006. January 20, 2005 event became the first clear response to GLE in thermal neutrons' data during the whole period of observations (from 1994). The biggest response observed at Antarctic experimental unit, was in good time correspondence with the response at Neutron Monitors (NMs). The difference of the amplitudes of the response at these units must be explained by different energy ranges of the registered particles. GLE on December 13, 2006 registered by one of Moscow thermal neutrons' units, corresponded to NM data both in amplitude and time of the observed effect. The absence of the response at another Moscow unit must be linked to energy spectra of this event different from the previous and higher sensitivity of the first unit to the relative low energy neutrons coming from above due to “thin roof”.