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A high-time resolution Neutron Monitor Database (NMDB) has started to be realized in the frame of the Seventh Framework Programme\ud of the European Commission. This database will include cosmic ray data from at least 18 neutron monitors distributed around\ud the world and operated in real-time. The implementation of the NMDB will provide the opportunity for several research applicationsmost of which will be realized in real-time mode. An important one will be the establishment of an Alert signal when dangerous solar\ud cosmic ray particles are heading to the Earth, resulting into ground level enhancements effects registered by neutron monitors. Furthermore,\ud on the basis of these events analysis, the mapping of all ground level enhancement features in near real-time mode will provide an\ud overall picture of these phenomena and will be used as an input for the calculation of the ionization of the atmosphere. The latter will beuseful together with other contributions to radiation dose calculations within the atmosphere at several altitudes and will reveal the\ud absorbed doses during flights. Moreover, special algorithms for anisotropy and pitch angle distribution of solar cosmic rays, which have\ud been developed over the years, will also be set online offering the advantage to give information about the conditions of the interplanetary\ud space. All of the applications will serve the needs of the modern world which relies at space environment and will use the extensivenetwork of neutron monitors as a multi-directional spectrographic detector. On top of which, the decreases of the cosmic ray intensity –\ud known as Forbush decreases – will also be analyzed and a number of important parameters such as galactic cosmic ray anisotropy will be\ud made available to the users of NMDB. A part of the NMDB project is also dedicated to the creation of a public outreach website with the scope to inform about cosmic rays and their possible effects on humans, technological systems and space-terrestrial environment. Therefore, NMDB will also stand as an informative gate on space research through neutron monitor's data usage.\ud © 2010 COSPAR. Published by Elsevier Ltd. All rights reserved

The relationship of lightning and elementary particle fluxes in the thunderclouds is not fully understood to date. Using the particle beams (the so-called Thunderstorm Ground Enhancements – TGEs) as a probe we investigate the characteristics of the interrelated atmospheric processes. The well-known effect of the TGE dynamics is the abrupt termination of the particle flux by the lightning flash. With new precise electronics, we can see that particle flux decline occurred simultaneously with the rearranging of the charge centers in the cloud. The analysis of the TGE energy spectra before and after the lightning demonstrates that the high-energy part of the TGE energy spectra disappeared just after lightning. The decline of particle flux coincides on millisecond time scale with first atmospheric discharges and we can conclude that Relativistic Runaway Electron Avalanches (RREA) in the thundercloud assist initiation of the negative cloud to ground lightning. Thus, RREA can provide enough ionization to play a significant role in the unleashing of the lightning flash.

Simultaneous measurements of the gamma ray differential energy spectra, electric field disturbances, and meteorological conditions provided by experimental facilities located at Mt. Aragats in Armenia allows to establish the model of particle acceleration and propagation in thunderstorm atmosphere. We present comparisons of measured and modeled thunderstorm ground enhancements (TGEs). The origin of the majority of TGEs is the MOS process -the modification of energy spectra of cosmic ray electrons in the atmospheric electric fields. The gamma ray differential energy spectra are well described by the power law function with indexes in the range −1.5 ÷ −2.5 for the electric field strengths 0.8-1.5 kV/cm at altitudes of 3400-5000 m a.s.l. The good agreement of the characteristics of experimental and simulated TGEs gives hope to estimate the intracloud electric field by the observed parameters of TGE gamma ray energy spectra.