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Related papers: Twists to Solar Spicules

200 papers

Alfv\'enic fluctuations are very common features in the solar wind and are found especially within the main portion of fast wind streams while the slow wind usually is less Alfv\'enic and more variable. In general, fast and slow wind show…

Space Physics · Physics 2018-12-19 Raffaella D'Amicis , Lorenzo Matteini , Roberto Bruno

We take stock of recent observations that identify the episodic plasma heating and injection of Alfvenic energy at the base of fast solar wind (in coronal holes). The plasma heating is associated with the occurrence of chromospheric…

Solar and Stellar Astrophysics · Physics 2015-06-05 Scott W. McIntosh

We perform a 2.5 dimensional magnetohydrodynamic (MHD) simulation to understand a comprehensive view of the formation of spicule-like cool jets due to initial transverse velocity pulses akin to Alfv\'en pulses in the solar chromosphere. We…

Solar and Stellar Astrophysics · Physics 2022-02-02 B. Singh , A. K. Srivastava , K. Sharma , S. K. Mishra , B. N. Dwivedi

Solar winds originate from the Sun and can be classified as fast or slow. Fast solar winds come from coronal holes at the solar poles, while slow solar winds may originate from the equatorial region or streamers. Spicules are jet-like…

Solar and Stellar Astrophysics · Physics 2024-12-25 R. Sadeghi , E. Tavabi

During Parker Solar Probe's first orbit, the solar wind plasma has been observed in situ closer than ever before, the perihelion on November 6th 2018 revealing a flow that is constantly permeated by large amplitude Alfv\'enic fluctuations.…

We use images of high spatial and temporal resolution, obtained with the Rapid Oscillations in the Solar Atmosphere instrument at the Dunn Solar Telescope, to reveal how the generation of transverse waves in Type I spicules is a direct…

Solar and Stellar Astrophysics · Physics 2015-06-03 D. B. Jess , D. J. Pascoe , D. J. Christian , M. Mathioudakis , P. H. Keys , F. P. Keenan

The effects of both density stratification and magnetic field expansion on torsional Alfven waves in solar spicules are studied. Also, their eigenfrequencies, eigenfunctions, and the period ratio P_1/P_2 are obtained with a novel…

Solar and Stellar Astrophysics · Physics 2015-06-19 Hossein Ebadi , Sadagat Shahmorad

Absorbtion of Alfven waves is considered to be the main mechanism of heating in the solar corona. It is concluded that the sharp increase of the plasma temperature by two orders of magnitude is related to a self-induced opacity with respect…

Astrophysics · Physics 2008-11-26 T. M. Mishonov , M. V. Stoev , Y. G. Maneva

We report the detection of oscillatory phenomena associated with a large bright-point group that is 430,000 square kilometers in area and located near the solar disk center. Wavelet analysis reveals full-width half-maximum oscillations with…

Solar and Stellar Astrophysics · Physics 2009-11-13 D. B. Jess , M. Mathioudakis , R. Erdelyi , P. J. Crockett , F. P. Keenan , D. J. Christian

Alfvenic waves are thought to play an important role in coronal heating and solar wind acceleration. Here we investigate the dissipation of standing Alfven waves due to phase mixing at the presence of steady flow and sheared magnetic field…

Solar and Stellar Astrophysics · Physics 2015-06-15 Z. Fazel , H. Ebadi

Alfv\'en waves, considered one of the primary candidates for heating and accelerating the fast solar wind, are ubiquitous in spacecraft observations, yet their origin remains elusive. In this study, we analyze data from the first 19…

We study the formation and evolution of a turbulent spectrum of Alfv\'en waves driven by reflection off the solar wind density gradients, starting from the coronal base up to 17 solar radii, well beyond the Alfv\'enic critical point. The…

Solar and Stellar Astrophysics · Physics 2009-07-22 A. Verdini , M. Velli , E. Buchlin

The observed sub-proton scale turbulence spectrum in the solar wind raises the question of how that turbulence originates. Observations of keV energetic electrons during solar quite-time suggest them as possible source of free energy to…

Solar and Stellar Astrophysics · Physics 2015-06-16 H. Che , M. L. Goldstein , A. F. Viñas

Recent observations have demonstrated that waves which are capable of carrying large amounts of energy are ubiquitous throughout the solar corona. However, the question of how this wave energy is dissipated (on which time and length scales)…

Solar and Stellar Astrophysics · Physics 2014-11-20 Jiajia Liu , Scott W. McIntosh , Ineke De Moortel , James Threlfall , Christian Bethge

To study motions and oscillations in the solar chromosphere and at the transition region (TR) level we analyze some extreme Doppler shifts observed off-limb with the Interface Region Imaging Spectrograph (IRIS). Raster scans and slit-jaw…

Solar and Stellar Astrophysics · Physics 2019-09-25 E. Tavabi , S. Koutchmy

Using data obtained by the EUV Imaging Spectrometer (EIS) onboard Hinode, we have per- formed a survey of obvious and persistent (without significant damping) Doppler shift oscillations in the corona. We have found mainly two types of…

Solar and Stellar Astrophysics · Physics 2012-10-31 Hui Tian , Scott W. McIntosh , Tongjiang Wang , Leon Ofman , Bart De Pontieu , Davina E. Innes , Hardi Peter

The aim here is to model the standing torsional oscillations in solar spicules in the presence of density stratification, magnetic field expansion, and steady flows. By implementing cylindrical geometry, the eigenfrequencies,…

Solar and Stellar Astrophysics · Physics 2016-04-27 H. Ebadi , S. Shahmorad , S. Vasheghani Farahani

Spicules are intermittently rising above the surface of the Sun eruptions; EUV jets are now also reported in immediately above layers. The variation of spicule orientation with respect to the solar latitude, presumably reflecting the…

Solar and Stellar Astrophysics · Physics 2021-07-27 E. Tavabi , S. Koutchmy

Recent near-sun solar-wind observations from Parker Solar Probe have found a highly dynamic magnetic environment, permeated by abrupt radial-field reversals, or "switchbacks." We show that many features of the observed turbulence are…

Space Physics · Physics 2020-03-04 Jonathan Squire , Benjamin D. G. Chandran , Romain Meyrand

We analyze the time series of Ca II H-line obtained from Hinode/SOT on the solar limb. We follow three cases of upwardly propagating kink waves along a spicule and inverted Y-shaped structures at the cusp of it. The time-distance analysis…

Solar and Stellar Astrophysics · Physics 2015-06-22 H. Ebadi , M. Ghiassi