Reply to “Comment on ‘Long lasting low energy thunderstorm ground enhancements and possible Rn-222 daughter isotopes contamination’”

Abstract

To identify the role of the gamma radiation from radon progenies in the long lasting thunderstorm ground enhancement (TGE) flux, a differential energy spectrum was measured with various spectrometers, including a precise ${3}^{\ensuremath{'}\ensuremath{'}}\ifmmode\times\else\texttimes\fi{}{3}^{\ensuremath{'}\ensuremath{'}}$ NaI(Tl) spectrometer from ORTEC (FWHM $\ensuremath{\sim}7.7%$ at 0.6 MeV). Measurements demonstrate that radon progenies radiation significantly contribute to the winter enhancements in the energy range below 0.3--2 MeV. However, performed Monte Carlo simulations and observation of TGEs with plastic scintillators of various thickness and energy thresholds show that TGEs originate in intracloud electric fields. Recent registration of gamma glows by spectrometers located on board aircraft flying at 12--20 km altitude also confirms an ``electric'' nature of particle flux enhancements.