Using Cosmic Ray for Monitoring and Forecasting Dangerous Solar Flare Events

Abstract

It is well known that in periods of great Solar Energetic Particles (SEP) fluxes of energetic particles can be so big that memory of computers and other electronics in space may be destroyed, satellites have serious anomalies: according to NOAA Space Weather Scales are dangerous Solar Radiation Storms S5-extreme with flux level of particles with energy > 10 MeV more than 10⁵cm^{− 2}s⁻¹, S4-severe (flux more than 10⁴) and S3-strong (flux more than 10³). In these periods is necessary to switch off some part of electronics for few hours to protect computer memories. These periods are also dangerous for astronauts on space-ships, and passengers and crew in commercial jets (especially during S5 storms). The problem is how to forecast exactly these dangerous phenomena. We show that exact forecast can be made by using high-energy particles (few GeV/nucleon and higher) which transportation from the Sun is characterized by much bigger diffusion coefficient than for small and middle energy particles. Therefore high energy particles came from the Sun much more early (8–20 minutes after acceleration and escaping into solar wind) than main part of smaller energy particles caused dangerous situation for electronics (about 30–60 minutes later). We describe here principles and experience of automatically working of program “SEP-Search”. The positive result which shows the exact beginning of SEP event on the Emilio Segre’ Observatory (2025 m above sea level, R _c = 10.8 GV), is determined now automatically by simultaneously increasing on 2.5 St. Dev. in two sections of neutron supermonitor (we determine also the probabilities of false and missed alerts). The next 1-min data the program “SEP-Search” uses for checking that the observed increase reflects the beginning of real great SEP or not. If yes, automatically starts to work on line the programs “SEPResearch” for determining spectrum of SEP out of atmosphere, spectrum in source, diffusion coefficient. To continue the SEP spectrum determining in low energy range, we use also available from Internet satellite data. Obtained results allow making forecast of radiation hazard for spacecrafts and aircrafts for about two days ahead on the basis of the first 30–40 minutes cosmic ray (CR) data. The work of NM on Mt. Hermon is supported by Israel (Tel Aviv University) -- Italian (Roma-Tre University and IFSI-CNR) collaboration. This research is in the frame of INTAS-810 and COST-724.