Context. For investigating spicules from the photosphere to coronal heights, the new Hinode/SOT long series of high-resolution observations from space taken in CaII H line emission offers an improved way to look at their remarkable dynamical behavior using images free of seeing effects. They should be put in the context of the huge amount of already accumulated material from groundbased instruments, including high-resolution spectra of off-limb spicules. Aims. Both the origin of the phenomenon and the significance of dynamical spicules for the heating above the top of the photosphere and the fuelling of the chromospheric and the transition region need more investigation, including of the possible role of the associated magnetic waves for the corona higher up. Methods. We analyze in great detail the proper transverse motions of mature and tall polar region spicules for different heights, assuming that there might be Helical-Kink waves or Alfvénic waves propagating inside their multicomponent substructure, by interpreting the quasi-coherent behavior of all visible components presumably confined by a surrounding magnetic envelop. We concentrate the analysis on the taller CaII spicules more relevant for coronal heights and easier to measure. Two-dimensional velocity maps of proper motion were computed for the first time using a correlation tracking technique based on FFTs and cross-correlation function with a 2nd-order-accuracy Taylor expansion. Highly processed images with the popular mad-max algorithm were first prepared to perform this analysis. The locations of the peak of the cross-correlation function were obtained with subpixel accuracy. Results. The surge-like behavior of solar polar region spicules supports the untwisting multicomponent interpretation of spicules exhibiting helical dynamics. Several tall spicules are found with (i) upward and downward flows that are similar at lower and middle levels, the rate of upward motion being slightly higher at high levels; (ii) the left-and righthand velocities are also increasing with height; (iii) a large number of multicomponent spicules show shearing motion of both left-and righthanded senses occurring simultaneously, which might be understood as twisting (or untwisting) threads. The number of turns depends on the overall diameter of the structure made of components and changes from at least one turn for the smallest structure to at most two or three turns for surge-like broad structures. The curvature along the spicule corresponds to a low turn number similar to a transverse kink mode oscillation along the threads.

Aims. We study the coherency of solar spicules intensity oscillations with increasing height above the solar limb in quiet Sun, active Sun and active region using observations from HINODE/SOT. Existence of coherency up to transition region strengthens the theory of the coronal heating and solar wind through energy transport and photospheric oscillations. Methods. Using time sequences from the HINODE/SOT in Ca II H line, we investigate oscillations found in intensity profiles at different heights above the solar limb. We use the Fourier and wavelet analysis to measure dominant frequency peaks of intensity at the heights, and phase difference between oscillations at two certain heights, to find evidence for the coherency of the oscillations. Finally, we can calculate the energy and the mass transported by spicules providing energy equilibrium, according to density values of spicules at different heights. To extend this work, we can also consider coherent oscillations at different latitudes and suggest to study of oscillations which may be obtained from observations of other satellites.Comment: 17 pages and 17 figs., Accepted in JOA

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In this research, we investigate Explosive Events (EEs) in the off-limb solar atmosphere, with simultaneous observations from the Si IV, Mg II k, and slit-jaw images (SJI) of the Interface Region Imaging Spectrograph (IRIS), on 17 August 2014, and 19 February. IRIS data can be investigated to observe the motion of matter, fluctuations, energy absorption, and heat transition of the solar atmosphere. Mechanisms responsible for solar large-scale structures, such as flares and coronal mass ejections, might originate from these small-scale energetic events. Therefore, the study of these events can be helpful for understanding mechanisms in mass and energy transport from the chromosphere toward the transition region and corona. We obtain intensity profiles from spectra in two altitudes, i.e., at the solar limb and 5 arcsec distance from solar limb, and then analyze the EE fluctuations at these two altitudes along the slit. We find that some spectral line profiles show enhancements in blue and red wings indicating upward and downward flows, and some profiles have opposite EEs in both wings. The amplitude of the Doppler velocity in the two data sets of different altitudes was approximated to be about 50 km s −1 . We calculated the phase velocity of the oscillations using a technique based on cross-correlation. The phase velocity is obtained as about 220 km s −1 . According to the periodic red and blue enhancements in EEs, we suggest that the fluctuations in the EEs with one side enhancement indicate a swaying motions of spicules about their axes, and those EEs observed in both wings indicate a rotational motions of spicules. The swaying and rotational motions are indicative of kink and torsional waves, respectively.

We investigate the role of active region spicules in the mass balance of the solar wind and energy supply for heating the solar atmosphere. We use high cadence observations from the Solar Optical Telescope (SOT) onboard the Hinode satellite in the Ca II H line filter obtained on 26 January 2007. The observational technique provides the high spatio-temporal resolution required to detect fine structures such as spicules. We apply Fourier power spectrum and wavelet analysis to SOT/Hinode time series of an active region data to explore the existence of coherent intensity oscillations. The presence of coherent waves could be an evidence for energy transport to heat the solar atmosphere.Using time series, we measure the phase difference between two intensity profiles obtained at two different heights, which gives information about the phase difference between oscillations at those heights as a function of frequency.The results of a fast Fourier transform (FFT) show peaks in the power spectrum at frequencies in the range from 2 to 8 mHz at four different heights (above the limb), while the wavelet analysis indicate dominant frequencies similar to, which is 10 60  times larger than the mass sufficiently energetic to accelerate the solar wind and heat the corona to temperatures of several million degrees. We  S. Zeighami