Ricevere le risonanze di Alfven (IAR)

Dopo la pubblicazione : http://air-radiorama.blogspot.it/2013/10/ricezioni-elf-in-condizioni-estreme.html
proseguono le esperienze estreme di Fabrizio Francione con la ricezione delle risonanze di Alfven
( IAR= Ionospheric Alfven Resonances) :http://www.sidmonitor.net/elf/index.html
Le risonanze di Shumann sono dovute eccitazione dei fulmini che fa risuonale la cavita' sferica formata dalla terra e la ionosfera .
Le risonanze di Alfven sono quelle striature orizzontali di rumore che si intravedono tra circa 1 e 4 Hz .
LA loro spiegazione di seguito :
In 1976, Polyakov (1976) predicted the existence of ionospheric Alfvén resonator (IAR), equivalent to the ionospheric waveguide, but operating in vertical direction with shear Alfvén waves. According to the theory, further developed by Polyakov and Rapoport (1981), waves can be trapped between two altitudes characterized by large Alfvén velocity gradients: the lower limit occurs at ionospheric F-layer, the upper limit at about 3000 km. For a review, see, e.g., Lysak (1993).

The so-called spectral resonance structures (SRS) discovered by Belyaev et al. (1989, 1990) are considered to be an evidence for IAR. They are thought to form within the IAR from electromagnetic emissions of lightning charges, just like the Schumann resonances. Up to fifteen bands can be observed, from the 1-2 Hz (Pc1 range) to well above the second Schumann resonance frequency at 14 Hz. After the original finding of SRS at mid-latitudes, they have now been observed also at high-latitudes (Belyaev et al., 1998)