Abraham Sternlieb

Monitoring and forecasting of great solar proton events using the neutron monitor network in real time

Obtaining online information on the onset of great solar energetic particle (SEP) events from real-time data of the neutron monitor network (NMN) is considered and the corresponding algorithm and program are proposed. Determination of the particle energy spectrum outside the atmosphere at different moments of the flare is considered on the basis of coupling functions method. The spectra defined in diffusion and kinetic approaches are compared. Using this information, the time of the SEP ejection into solar wind, the energy spectrum of a SEP event in the source inside the solar corona, and the SEP diffusion coefficient in the interplanetary space during the flare can be estimated. In this work, the significant possibility of the expected SEP fluxes and the energy spectrum forecasting on the early part of the increasing SEP intensity (about 20-30 min after the onset) is considered. Available satellite data in real-time scale combined with real time-data from neutron monitors (NM) are used for extrapolation of this forecast to the region of very small energy particles. The method is checked on the SEP event of September 1989. It is important to note that the accuracy of the developed method sufficiently increases with the increasing dangerous level of the SEP event. The method is not CPU damaging and can run in real time, providing inexpensive means of SEP prediction.

Forward to automatic forecasting and estimation of expected radiation hazards level

We present method of automatically forecasting of solar cosmic ray (SCR) impact caused by solar flare and estimation of radiation hazard level. We use model of solar cosmic ray diffusion in general form and coupling functions for neutron monitors network with different altitudes and cut-off rigidities, including also space detectors like GOES-11, 12. Another observational data for estimation of energy spectra is multiplicity of CR registration by some neutron monitors. We demonstrate algorithms for automatic estimation of the event starting, determination time-evolution of SCR in space by coupling functions in the frame of spectrographic method, solving inverse problem for SCR generation in solar corona and propagation in the interplanetary space, automatic determining on the basis of CR observation data parameters of SCR generation in solar corona, escaping into solar wind, and propagation in space. We show that on the basis of these parameters it can be automatic forecasting on the basis of first about 0.5 hour data expected level of radiation hazards for full time of event (up to about 48 hours) for objects in space on different distances from the Sun, in magnetosphere at different orbits, and in atmosphere at different altitudes and cutoff rigidities. If for some objects expected level of radiation hazards will be dangerous, after about 0.5 hour from event beginning will be formatted and sent corresponding Alert. We take into account that for the first about 0.5 hour data from event beginning, when coming mostly only small flux of high energy particles – radiation hazards expected very small in comparison with more delay time when coming main part of SCR with energy  1 GeV, formatted sufficient part of radiation hazards.