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We consider a first important parameter of spicules as observed above the solar visible limb: their apparent diameter as a function of the height above the limb which determines their aspect ratio and leads to the discussion of their…

Solar and Stellar Astrophysics · Physics 2015-05-18 E. Tavabi , S. Koutchmy , A. Ajabshirizadeh

We amassed statistics for quiet-sun chromosphere spicules at the limb using ground-based observations from the Swedish 1-m Solar Telescope on La Palma and simultaneously from NASA's Transition Region and Coronal Explorer (TRACE) spacecraft.…

Solar and Stellar Astrophysics · Physics 2010-11-01 Jay M. Pasachoff , William A. Jacobson , Alphonse C. Sterling

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…

Solar and Stellar Astrophysics · Physics 2015-07-15 E. Tavabi , A. Ajabshirizadeh , A. R. Ahangarzadeh Maralani , S. Zeighami

Wave theories of heating the chromosphere, corona, and solar wind due to photospheric fluctuations are strengthened by the existence of observed wave coherency up to the transition region (TR). The coherency of solar spicules' intensity…

Solar and Stellar Astrophysics · Physics 2017-02-08 Alireza Ahangarzadeh Maralani , Ehsan Tavabi , Ali Ajabshirizadeh

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…

Solar and Stellar Astrophysics · Physics 2016-03-23 S. Zeighami , A. R. Ahangarzadeh Maralani , E. Tavabi , A. Ajabshirizadeh

Broad-band images in the Ca II H line, from the BFI instrument on the Hinode spacecraft, show emission from spicules emerging from and visible right down to the observed limb. Surprisingly, little absorption of spicule light is seen along…

Solar and Stellar Astrophysics · Physics 2015-05-18 Philip G. Judge , Mats Carlsson

We present constraints on the structure of the chromosphere from observations of the Ca II H line profile near and off the solar limb. We obtained a data set of the Ca II H line in a field of view extending 20" across the limb. We analyzed…

Solar and Stellar Astrophysics · Physics 2015-05-28 C. Beck , R. Rezaei

This thesis is based on observations performed at the Vacuum Tower Telescope (Tenerife). We have used an infrared spectropolarimeter (TIP) and a Fabry-Perot spectrometer (G-FPI) from years 2004 to 2006. We have applied several imaging…

Solar and Stellar Astrophysics · Physics 2009-02-19 Bruno Sánchez-Andrade Nuño

We estimate the formation height range contributing to broad-band and narrow-band filter imaging data in Ca II H to investigate whether spicules can be detected in such observations at the centre of the solar disc. We apply spectral filters…

Solar and Stellar Astrophysics · Physics 2015-06-16 C. Beck , R. Rezaei , K. G. Puschmann

Solar limb and disc spicule quasi- periodic motions have been reported for a long time, strongly suggesting that they are oscillating. In order to clear up the origin and possibly explain some solar limb and disc spicule quasi-periodic…

Solar and Stellar Astrophysics · Physics 2015-05-27 E. Tavabi , S. Koutchmy , A. Ajabshirizadeh

We analyze the time series of Ca ii H-line obtained from Hinode/SOT on the solar limb. The time-distance analysis shows that the axis of spicule undergoes quasi-periodic transverse displacement. We determined the period of transverse…

Solar and Stellar Astrophysics · Physics 2015-07-28 V. Abbasvand , H. Ebadi , Z. Fazel

Exploiting high-resolution observations made by the Solar Optical Telescope onboard Hinode, we investigate the spatial distribution of power spectral density of oscillatory signal in and around NOAA active region 10935. The G-band data show…

I present a study of high-resolution time series of Ca II H images and Fe I 630.15 nm spectra taken with the Solar Optical Telescope on the Hinode spacecraft. There is excellent correspondence between the Ca II H and Fe I line core…

Solar and Stellar Astrophysics · Physics 2021-02-03 A. G. de Wijn

We have analyzed IRIS spectral and slit-jaw observations of a quiet region near the South Pole. In this article we present an overview of the observations, the corrections, and the absolute calibration of the intensity. We focus on the…

Solar and Stellar Astrophysics · Physics 2018-01-09 C. E. Alissandrakis , J. -C. Vial , A. Koukras , E. Buchlin , M. Chane-Yook

Spicules are ubiquitous, fast moving jets observed off-limb in chromospheric spectral lines. Combining the recently-launched Interface Region Imaging Spectrograph with the Solar Dynamics Observatory and Hinode, we have a unique opportunity…

Solar and Stellar Astrophysics · Physics 2015-05-12 H. Skogsrud , L. Rouppe van der Voort , B. De Pontieu , T. M. D. Pereira

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

Aims. With the Solar Optical Telescope on Hinode, we investigate the basic properties of high-degree solar oscillations observed at two levels in the solar atmosphere, in the G-band (formed in the photosphere) and in the Ca II H line…

Astrophysics · Physics 2009-11-13 U. Mitra-Kraev , A. G. Kosovichev , T. Sekii

Small-scale magnetic flux concentrations contribute significantly to the brightness variations of the Sun, yet observing them - particularly their magnetic field - near the solar limb remains challenging. Solar Orbiter offers an…

Solar and Stellar Astrophysics · Physics 2026-02-11 K. Albert , J. Hirzberger , N. A. Krivova , X. Li , D. Calchetti , G. Valori , J. Sinjan , S. K. Solanki , A. Gandorfer , J. Woch , D. Orozco Suárez , S. Parenti

We analyze the time series of CaII H-line obtained from Hinode/SOT on the solar limb. The time-distance analysis shows that the axis of spicule undergos quasi-periodic transverse displacement at different heights from the photosphere. The…

Solar and Stellar Astrophysics · Physics 2012-09-26 H. Ebadi , T. V. Zaqarashvili , I. Zhelyazkov

Solar spicules are chromospheric fibrils that appear everywhere on the Sun, yet their origin is not understood. Using high resolution observations of spicules obtained with the Swedish 1-m Solar Telescope, we aim to understand how spicules…

Solar and Stellar Astrophysics · Physics 2016-06-22 Tiago M. D. Pereira , Luc Rouppe van der Voort , Mats Carlsson
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