Doppler shift oscillations in solar spicules

T. V. Zaqarashvili; E. Khutsishvili; V. Kukhianidze; G. Ramishvili

doi:10.1051/0004-6361:20077661

Home/Archive/arXiv

arXiv · 0708.2057

Doppler shift oscillations in solar spicules

T. V. Zaqarashvili·E. Khutsishvili·V. Kukhianidze·G. Ramishvili

View original source ↗Read source document ↗Export metadata ↓

Abstract

Consecutive height series of Ha 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. The aim is to observe oscillatory phenomena in spicules and consequently to trace wave propagations through the chromosphere. The Discrete Fourier Transform analysis of Ha Doppler shift time series constructed from the observed spectra at each height is used. 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. 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 about 6000 km above the photosphere is estimated as 12-15 G.

Explore related subjects

astro-ph

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

T. V. Zaqarashvili, E. Khutsishvili, V. Kukhianidze, G. Ramishvili. 2007-08-15. Doppler shift oscillations in solar spicules. https://doi.org/10.1051/0004-6361%3A20077661

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Cosmic Conundrums with Quantum Corrections

Darh energy was discovered over 25 years ago and we do not have an explanation of it. Dark matter comprises 95% of matter in the universe and we still don't know what it is. The Webb telescope has been finding fully formed galaxies with massive black holes millions of times the mass of the sun in the early universe and we don't have any explanation. A quantum density limitation will be used to solve these and other outstanding problems.

astro-ph↗

arXiv2026

On binary pulsars and the force of gravity

The energy-momentum budget of the astrophysical systems can be studied by the exact local conservation equation derived by Landau and Lifshitz. We show that a similar equation is valid for the Einstein-Cartan gravity. We reanalyze a binary pulsar system using the Landau-Lifshitz conservation equation and show that the orbital period change rate can be completely understood as a curvature backreaction process. Taking into account the detailed theoretical and observational research of relativistic binary pulsar systems, especially the system of Hulse and Taylor, we conclude that general relativity and astrophysical observations rule out the existence of gravitational radiation. We comment upon the LIGO GW events and their alternative explanation, as well as the recent pulsar timing arrays data.

astro-ph↗

arXiv2026

Oscillation frequencies and mode lifetimes in alpha Centauri A

We analyse our recently-published velocity measurements of alpha Cen A (Butler et al. 2004). After adjusting the weights on a night-by-night basis in order to optimize the window function to minimize sidelobes, we extract 42 oscillation frequencies with l=0 to 3 and measure the large and small frequency separations. We give fitted relations to these frequencies that can be compared with theoretical models and conclude that the observed scatter about these fits is due to the finite lifetimes of the oscillation modes. We estimate the mode lifetimes to be 1-2 d, substantially shorter than in the Sun.

astro-ph↗