Injection of relativistic electrons during the giant SSC and the greatest magnetic storm of the space era Original Research Article

We study the variations of relativistic electrons in the magnetosphere during the two extraordinary events of the space era: an SSC on 24 March 1991 and a superstorm on 13 March 1989. We analyze the experimental data from four sensors measured electrons in the energy range 0.17–8 MeV on the METEOR satellites (polar orbit with ≈900 km altitude). For March 1991, we study the developing of a new radiation belt of relativistic electrons which has been created in this event. A giant SSC built a “shock-injected” belt with its peak at L∼2.8 (for >8 MeV electrons). During the main phase of the following strong magnetic storm (|Dst|max≈300 nT), the peak moved to the lower L-shells and finally reached L≈2.3.This position did not change on the recovery phase of the storm.Another, “storm-injected” belt has been formed during the storm recovery at Lmax≈3. In this latter belt, an intensity of the higher energy electrons increased with a delay in comparison with the intensity of lower-energy electrons (full energy range of the comparison is 0.17–3 MeV). Both new belts are well distinguished in our data. In the another case, 13 March 1989, we observed relativistic electrons during a superstorm with |Dst|max∼600 nT. In this event, maximum intensity of the new “storm-injected” belt appeared at L∼2.5 for all energies up to 8 MeV. L-position of the “storm-injected” belts in both observed cases of high-amplitude Dst well agrees with the earlier developed formula: |Dst|max=2.75.104/L4max.