The physical nature of the upper subsidiary diffuse resonances


  • Vladimir A. Osherovich


The upper subsidiary diffuse resonances were first observed in the ionosphere in the Alouette 2 topside sounder experiment, later by the ISIS 1 satellite, and then by the JIKIKEN (EXOS B) satellite during its electron injection experiment. The frequencies of the subsidiary resonances are just higher than those of the diffuse resonances Dn (n = 1, 2, 3, 4). In our work we identify the upper subsidiary diffuse resonance as a hybrid resonance of the diffuse and cyclotron resonances. The corresponding frequencies are fT,Dn = (f²Dn + f²H)1/2, n = 1, 2, 3, 4 ⋯, where fT,Dn is the observed frequency of the nth upper subsidiary diffuse resonance, fDn is the frequency of the nth diffuse resonance, and fH is the electron gyrofrequency.