Abstract
With the developed by the authors of a ground level enhancements events (GLE) modeling technique, the modeling study of 35 large GLEs for the period 1956 - 2006 has been carried out. The basic characteristics of relativistic solar protons (RSP) are obtained: a rigidity (energetic) spec- trum, anisotropy axis direction, and pitch angle distributions for each event. It is shown that in nearly all events there ex- isted two components (population) of relativistic solar par- ticles: prompt and delayed. The prompt component (PC) prevails in the beginning of the event. It is characterized by an impulsive profile, strong anisotropy and exponential en- ergetic spectrum. The delayed component (DC) dominates during maximum and decline phases of the events. It has a gradual intensity profile, moderate anisotropy and a power law energetic spectrum. The analysis of the large number GLE shows the value of a characteristic energy in the expo- nential spectrum of PC has rather stable meaning 0.5 GeV and well agrees with the spectrum of protons accelerated in an electric field arising during the magnetic reconnection in the solar corona. The value of a spectral exponent of the power law spectrum of DC is distributed from 4 up to 6 with most at 5. This is close to the simulated spectrum arising in the process of stochastic acceleration in turbulent solar plasma. solar protons (RSP) from the data of the worldwide network of neutron monitors. These are: rigidity (energy) spectrum, direction of anisotropy axis, and pitch angle distributions. Dynamics of these parameters in each event were studied. It is shown that in nearly all events there existed two compo- nents (populations) of relativistic solar particles: prompt and delayed ones. The prompt component (PC) prevails in the beginning of the event. It is characterized by an impulsive profile, a strong anisotropy and an exponential energetic spectrum. The de- layed component (DC) dominates during maximum and de- cline phases of the events. It has a gradual intensity profile, a moderate anisotropy and a power law energy spectrum. The averaged parameters of the PC and DC spectra and their pos- sible connection to probable mechanisms of acceleration on the Sun were studied. The acceleration by electric field in the region of magnetic reconnection for the PC and the stochas- tic acceleration in the turbulent plasma for the DC are con- sidered the most probable of these mechanisms.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
