PR#37: 24-th Solar activity cycle produce first violent blast, now ramping up toward a solar maximum around 2013. The sun unleashed its strongest solar flare in nearly five years at Feb 15 night, sending a massive wave of charged particles toward Earth. A huge cloud of charged particles, named coronal mass ejection (CME) reach the Earth in approximately 3 days and trigger sizeable geomagnetic storm and deep Forbush decrease (Fd). Fd is a rapid decrease in the observed galactic cosmic ray intensity following a CME arrival, it occurs due to the magnetic field of the plasma solar wind sweeping some of the galactic cosmic rays away from Earth. Particle detectors of the Aragats Space Environmental Center (ASEC) and SEVAN worldwide network registered the Fd in all details.

In Figure 1 we post the intensity changes of the neutral and charged particles measured at Aragats 3250 m above sea level.

In Figure 2 we demonstrate first results from the particle monitors of new type located at Aragats in Bulgaria and Croatia. The data from monitors located on different longitudes, latitudes and altitudes allows disentangling solar-terrestrial connections and creating and testing models of interactions of fast solar wind with magnetosphere and many others.

Figure 1. Pressure corrected time series of ASEC particle monitors

Figure 2. Pressure corrected time series of SEVAN particle monitors