The observation of Ground Level Enhancement GLE 77 by the neutron detectors of the Experimental Complex NEVOD

TL;DR

This paper reports the first observation of a Ground Level Enhancement (GLE 77) by neutron detectors at NEVOD, enabled by recent setup upgrades, providing new insights into neutron flux variations during such events.

Contribution

It introduces the first use of neutron detectors oriented for extensive air shower studies to observe a GLE, demonstrating the potential of the upgraded experimental setup.

Findings

Detection of a significant neutron flux increase during GLE 77

First observation of GLE using neutron detectors oriented for air shower studies

Preliminary analysis confirms the event's characteristics

Abstract

A Ground Level Enhancement event was observed by neutron detectors designed for the registration of extensive air showers at the Experimental Complex NEVOD. The potential for that was unlocked by a recent modernization of the experimental setup that included implementation of additional channels for measuring neutron flux variation. At 10:15 UT on November 11, 2025, a sudden and significant increase in the neutron flux was detected by two installations: PRISMA-36 and URAN arrays. For the first time, a GLE has been recorded using a set of neutron detectors oriented at the extensive air shower studies. We present the measured EC NEVOD data and the results of the preliminary analysis of the observed GLE.