Context. Consecutive height series of Hα spectra in solar limb spicules taken on the 53 cm coronagraph of Abastumani Astrophysical Observatory at the heights of 3800-8700 km above the photosphere have been analyzed. Aims. The aim is to observe oscillatory phenomena in spicules and consequently to trace wave propagations through the chromosphere.Methods. The Discrete Fourier Transform analysis of Hα Doppler shift time series constructed from the observed spectra at each height is used.Results. Doppler velocities of solar limb spicules show oscillations with periods of 20-55 and 75-110 s. There is also the clear evidence of 3-min oscillations at the observed heights.Conclusions. The oscillations can be caused by wave propagations in thin magnetic flux tubes anchored in the photosphere. We suggest the granulation as a possible source for the wave excitation. Observed waves can be used as a tool for spicule seismology; the magnetic field strength in spicules at the height of ∼ 6000 km above the photosphere is estimated as 12 − 15 G.

Height series of Hα spectra in solar limb spicules obtained with the 53 cm coronagraph of the Abastumani Astrophysical Observatory are analyzed. Each height series covered 8 different heights beginning at 3800 km above the photosphere. The spatial difference between neighboring heights was 1 , consequently ∼3800−8700 km distance above the photosphere has been covered. The total time duration of each height series was 7 s. We found that nearly 20% of measured height series show a periodic spatial distribution of Doppler velocities. We suggest that this spatial periodicity in Doppler velocity is caused by propagating kink waves in spicules. The wave length is found to be ∼3500 km. However the wave length tends to be ∼1000 km at the photosphere due to the height variation of the kink speed. This probably indicates to a granular origin for the waves. The period of waves is estimated to be in the range of 35−70 s. These waves may carry photospheric energy into the corona, therefore can be of importance in coronal heating.

D 3 and Hc~ line spectrograms of spicules are analysed. The spectrograms are obtained with a specific device attached to the 53 cm coronagraph of Abastumani Astrophysical Observatory. Certain results are derived, based on the observational material consisting of 70 height series spectrograms taken over a period of 44 min in Hc~ line and 60 height series spectrograms taken over a period of 30 min in D 3. Each series involves 8 spectrograms reflecting the state of spicules at eight different heights in the chromosphere.

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