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Narrow-band (NB) events in dynamic spectra and their relation with short (S-) bursts are an unresolved enigma of the Jovian decametric emission. This paper is focused on the S/NB-structure with timescales between 0.03 s and 0.3 s. We show that the main S/NB-phenomenology can be reduced to three main ingredients which are: the dispersion delay of the radio emission, the motion of emitting electrons in the parallel electric field of the standing Alfv´en wave, and the shadow effect.

The paper deals with interpretation of long-periodic (minutes, e.g. < 0.01 Hz) modulations, detected in the microwave records during flaring events on the Sun, as the signatures of large scale transverse oscillations of coronal loops, observed at the same time by TRACE. In the case of transverse large scale oscillatory motions of a loop a properly located observer, besides of the modulation caused by motion of the emission diagram pattern at the main oscillation frequency, may see also a modulation at double frequency of the loop oscillation, resulted by a varying magnetic field during each inclination of the loop, as well as weaker higher harmonics. Identification of such ”modulation pairs” in the dynamic spectra of solar microwave emission and their association with the observed oscillating coronal loops form the major result of the undertaken investigation. Three different events with the detected by TRACE post-flare oscillating loops were considered in that study (Mar.23,2000; Sep.15,2001; Sep.07,2001).

The global distribution of solar surface activity (active regions) is connected with processes in the convection zone. To extract the information on large-scale motions in the convection zone, we study the solar synoptic charts (Mount Wilson 1998-2004, Fe I, 525.02 nm). The clear indication of large-scale (= 18°) turbulence is found. This may be a manifestations of the deep convection because there is no such global turbulent eddies in the solar photosphere. The preferred scales of longitudinal variations in surface solar activity are revealed. These correspond to ~ 15° to 51° (gigantic convection cells), 90°, 180° and 360°. Similar scales (e.g., 40° and 90°) are found in the millimeter radio-images (Mets¨ahovi Radio Observatory 1994-1998, 37 and 87 GHz). Hence, the millimeter radio astronomy could prove useful for remote sensing of the solar convection zone.

The paper deals with interpretation of long-periodic (minutes, e.g. < 0.01 Hz) modulations, detected in the microwave records during flaring events on the Sun, as the signatures of large scale transverse oscillations of coronal loops, observed at the same time by TRACE. In the case of transverse large scale oscillatory motions of a loop a properly located observer, besides of the modulation caused by motion of the emission diagram pattern at the main oscillation frequency, may see also a modulation at double frequency of the loop oscillation, resulted by a varying magnetic field during each inclination of the loop, as well as weaker higher harmonics. Identification of such ”modulation pairs” in the dynamic spectra of solar microwave emission and their association with the observed oscillating coronal loops form the major result of the undertaken investigation. Three different events with the detected by TRACE post-flare oscillating loops were considered in that study (Mar.23,2000; Sep.15,2001; Sep.07,2001).

The global distribution of solar surface activity (active regions) is connected with processes in the convection zone. To extract the information on large-scale motions in the convection zone, we study the solar synoptic charts (Mount Wilson 1998-2004, Fe I, 525.02 nm). The clear indication of large-scale (= 18°) turbulence is found. This may be a manifestations of the deep convection because there is no such global turbulent eddies in the solar photosphere. The preferred scales of longitudinal variations in surface solar activity are revealed. These correspond to ~ 15° to 51° (gigantic convection cells), 90°, 180° and 360°. Similar scales (e.g., 40° and 90°) are found in the millimeter radio-images (Mets¨ahovi Radio Observatory 1994-1998, 37 and 87 GHz). Hence, the millimeter radio astronomy could prove useful for remote sensing of the solar convection zone.

Narrow-band (NB) events in dynamic spectra and their relation with short (S-) bursts are an unresolved enigma of the Jovian decametric emission. This paper is focused on the S/NB-structure with timescales between 0.03 s and 0.3 s. We show that the main S/NB-phenomenology can be reduced to three main ingredients which are: the dispersion delay of the radio emission, the motion of emitting electrons in the parallel electric field of the standing Alfv´en wave, and the shadow effect.