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

Energetic proton measurements obtained from the GOES and IMP-8 satellites as well as from ground-based neutron monitors are compared with the GOES soft X-ray measurements of the associated solar flares for the period 1975-2003. The present study investigates a broad range of phenomenology relating proton events to flares (with some references to related interplanetary disturbances), including correlations of occurrence, intensities, durations and timing of both the particle event and the flare as well as the role of the heliographic location of the designated active region. 1144 proton events of >10 MeV energy were selected from this 28-year period. Owing primarily to the low particle flux threshold employed more than half of this number was found to be reliably connected with an X-ray flare. The statistical analysis indicates that the probability and magnitude of the near-Earth proton enhancement depends critically on the flare's importance and its heliolongitude. In this study all flares of X-ray importance >X5 and located in the most propitious heliolongitude range, 15 • W to 75 • W, were succeeded by a detectable proton enhancement. It was also found that the heliolongitude frequently determines the character of the proton event time profile. In addition to intensity, duration and timing, proton events were found to be related to the other flare properties such as lower temperatures and longer loop lengths.

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A database combining information about solar proton enhancements (SPEs) near the Earth and soft X-ray flares (GOES measurements) has been used for the study of different correlations through the period from 1975 to May 2006. The emphasis of this work is on the treatment of peak-size distributions of SXR flares and SPEs. The frequency of SXR flares and solar proton events (>10 and >100 MeV, respectively) for the past three solar cycles has been found to follow mainly a power-law distribution over three to five orders of magnitude of fluxes, which is physically correct beyond the "sensitivity" problem with the smallest peak values. The absence of significant spectral steepening in the domain of the highest peak values demonstrates that during the period considered, lasting 30 years, the limit of the highest flare's energy release has not yet been achieved. The power-law exponents were found to be −2.19 ± 0.04, −1.34 ± 0.02, and −1.46 ± 0.04, for the total SXR flare distribution and the total SPE distributions (for both E P > 10 MeV and E P > 100 MeV), respectively. For SPEs associated with flares located to the West of 20°W, the exponents are −1.22 ± 0.05 (E P > 10 MeV) and −1.26 ± 0.03 (E P > 100 MeV). The size distribution for corresponding flares follows a power law with a slope of −1.29 ± 0.12. Thus, X-ray and proton fluxes produced in the same solar events have very similar distribution shapes. Moreover, the derived slopes are not incompatible with a linear dependence between X-ray flare power and proton fluxes near the Earth. A similar statistical relation is obtained independently from the direct comparison of the X-ray and proton fluxes. These all argue for a statistically significant relationship between X-ray and proton emissions.