THE RELATIONSHIP BETWEEN LOW-FREQUENCY OSCILLATIONS IN THE CHROMOSPHERE AND BACKGROUND MAGNETIC-FIELDS

Based on results of two-day observations in the wings of the H-alpha-line it has been established that: (a) there exist in the chromosphere low-frequency oscillations, whose periods are close to those of the solar limb (Brown et al. 1978) as well as of coronal loops in soft X-rays (Harrison 1987). (b) The wavelength of these oscillations is 600-700 Mm and is comparable with the scale of background magnetic field in the direction parallel to the equator. (c) The amplitude of low-frequency oscillations is enhanced substantially at filament sites.