alfvén waves dissipation is an extensively studied mechanism for the coronal heating problem. these waves can be generated by magnetic reconnection and propagated along the reconnected field lines. here, we study the generation of alfvén waves at the presence of both steady flow and sheared magnetic field in the longitudinally density stratified of solar spicules. the initial flow is assumed to...

Alfvén waves dissipation is an extensively studied mechanism for the coronal heating problem. These waves can be generated by magnetic reconnection and propagated along the reconnected field lines. Here, we study the generation of Alfvén waves at the presence of both steady flow and sheared magnetic field in the longitudinally density stratified of solar spicules. The initial flow is assumed to...

An attractive diagnostic tool for investigating the magnetism of the solar chromosphere is the observation and theoretical modeling of the Hanle and Zeeman effects in spicules, as shown in this letter for the first time. Here we report on spectropolarimetric observations of solar chromospheric spicules in the He i 10830 Å multiplet and on their theoretical modeling accounting for radiative tran...

One of the important parameters of the ubiquitous spicules rising intermittently above the surface of the Sun is the variation of spicule spline orientation with respect to the solar coordinates, presumably reflecting the focusing of ejection by the coronal magnetic field. Here we first use a method of tracing limb spicules using a combination of second derivative operators in multiple directio...

We compare simultaneous sequences of Hα and He ii 304Å images near the solar limb. We propose to distinguish polar surges and giant spicules (macrospicules), among the He ii structures observed beyond the solar limb. Polar surges have a complex structure when observed in Hα and an erup-tive nature, reminiscent of normal surges in small scale. Giant spicules are simple spikes, very narrow compar...

Interaction of Alfven waves with plasma inhomogeneity generates phase mixing which can cause the dissipation of Alfven waves. We investigated the dissipation of standing Alfven waves due to phase mixing at the presence of steady flow and sheared magnetic field in solar spicules. Moreover, the transition region between chromosphere and corona was considered. Our numerical simulation showed that ...

Motivated by recent observations of spicules and macrospicules in the far-ultraviolet (FUV) wavelength range with the Solar Ultraviolet Measurements of Emitted Radiation spectrograph (SUMER) on the Solar and Heliospheric Observatory (SOHO), a generation mechanism for spicules and macrospicules is outlined which deviates significantly from most of the previous concepts. The important aspect is t...

Aims. Off-the-limb observations with high spatial and spectral resolution will help us understand the physical properties of spicules in the solar chromosphere. Methods. Spectropolarimetric observations of spicules in the He  10830 Å multiplet were obtained with the Tenerife Infrared Polarimeter on the German Vacuum Tower Telescope at the Observatorio del Teide (Tenerife, Spain). The analysis ...

One of the most enduring mysteries in solar physics is why the Sun’s outer atmosphere, or corona, is millions of kelvins hotter than its surface. Among suggested theories for coronal heating is one that considers the role of spicules – narrow jets of plasma shooting up from just above the Sun’s surface – in that process (Athay & Holzer, 1982; Athay, 2000). For decades, it was thought that spicu...