Great SEP events and space weather: 3. Automatic determination of the diffusion coefficient in the interplanetary space, the time of ejection and the energy spectrum in the source
Abstract
In Applbaum et al. (2010) it was described how the "SEP-Research/Spectrum" program works automatically, determining on the basis of on-line one-minute NM data the SEP spectrum on the Earth. We show that after this, one can determine the time of ejection, the diffusion coefficient in the interplanetary space and the energy spectrum in the source of the SEP. We consider several possibilities: 1) one of these three parameters is unknown, 2) two of these three parameters are unknown, 3) all three parameters are unknown. We show that in the first case, it is necessary to determine the energy spectrum of SEP at Earth at two different moments in time, and that from two equations the unknown parameter can be determined automatically (for example, the energy spectrum in the source or the diffusion coefficient, or the time of ejection; the determination is made from one equation, and the other is used as a control of the model used). In the second case, it is necessary to determine the energy spectrum of SEP at Earth at three different moments in time, and from three equations one can determine automatically the other two parameters (for example, the energy spectrum in the source and the diffusion coefficient in the interplanetary space). In the third case, by using data for four different moments in time, one can determine all three unknown parameters (the time of ejection, the diffusion coefficient in the interplanetary space, and the energy spectrum in source of SEP), and one equation can be used as a control for the model. We describe in detail the algorithms of the programs "SEP-Research/Time of Ejection," "SEP-Research/Source" and "SEP-Research/Diffusion." We show how these programs worked on examples of some historical great SEP events.
- Publication:
-
38th COSPAR Scientific Assembly
- Pub Date:
- 2010
- Bibcode:
- 2010cosp...38.4231A