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Related papers: Slender Ca II H Fibrils Mapping Magnetic Fields in…

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We present observations of transverse oscillations in slender Ca II H fibrils (SCFs) in the lower solar chromosphere. We use a 1 hr long time series of high- (spatial and temporal-) resolution seeing-free observations in a 0.11 nm wide…

We use seeing-free high spatial resolution Ca II H data obtained by the SUNRISE observatory to determine properties of slender fibrils in the lower solar chromosphere. In this work we use intensity images taken with the SUFI instrument in…

We report the detection of oscillations in slender Ca II H fibrils (SCFs) from high-resolution observations acquired with the Sunrise balloon-borne solar observatory. The SCFs show obvious oscillations in their intensity, but also their…

Filtergrams obtained in Ca II H, Ca II K and H-alpha are often employed as diagnostics of the solar chromosphere. However, the vastly disparate appearance between the typical filtergrams in these different lines calls into question the…

Astrophysics · Physics 2015-05-13 K. P. Reardon , H. Uitenbroek , G. Cauzzi

Broad-band images of the solar chromosphere in the Ca II H&K line cores around active regions are covered with fine bright elongated structures called bright fibrils. The mechanisms that form these structures and cause them to appear bright…

Solar and Stellar Astrophysics · Physics 2020-05-06 Sepideh Kianfar , Jorrit Leenaarts , Sanja Danilovic , Jaime de la Cruz Rodríguez , Carlos José Díaz Baso

Context: Except for the Ca II resonance lines, fibrils are ubiquitously present in most high-resolution observations of chromospheric lines. Aims: We show that fibrils are also a prevailing feature in Ca II K, provided the…

Solar and Stellar Astrophysics · Physics 2015-05-13 A. Pietarila , J. Hirzberger , V. Zakharov , S. K. Solanki

(Abridged) Aims: In this paper, we seek to establish the suitability of imaging spectroscopy performed in the Ca II 854.2 nm line as a means to investigate the solar chromosphere at high resolution. Methods: We utilize monochromatic images…

Recent advances in observational performance and numerical simulations have revolutionised our understanding of the solar chromosphere. This concerns in particular the structure and dynamics on small spatial and temporal scales. As a…

Solar and Stellar Astrophysics · Physics 2009-12-01 Sven Wedemeyer-Böhm

Observations of the solar chromosphere in the line-core of the \Halpha\ line show dark elongated structures called fibrils that show swaying motion. We performed a 3D radiation-MHD simulation of a network region, and computed synthetic…

Solar and Stellar Astrophysics · Physics 2015-06-23 Jorrit Leenaarts , Mats Carlsson , Luc Rouppe van der Voort

Small-scale umbral brightenings (SSUBs), umbral microjets, spikes or short dynamic fibrils (SDFs), and umbral dark fibrils are found in any observation of the chromosphere with sufficient spatial resolution. We study the spatial and…

Solar and Stellar Astrophysics · Physics 2020-10-28 Vasco M. J. Henriques , Chris J. Nelson , Luc H. M. Rouppe van der Voort , Mihalis Mathioudakis

The fine-structure of magnetic field of a sunspot penumbra in the upper chromosphere is to be explored and compared to that in the photosphere. High spatial resolution spectropolarimetric observations were recorded with the 1.5-meter GREGOR…

Sunspot chromospheres display vigorous oscillatory signature when observed in chromospheric diagnostics like the strong Ca II lines and H-alpha. New high-resolution sunspot observations from the Swedish 1-m Solar Telescope show the…

Solar and Stellar Astrophysics · Physics 2015-06-16 Luc Rouppe van der Voort , Jaime de la Cruz Rodriguez

Aims. To understand the morphology of the chromosphere in sunspot umbra. We investigate if the horizontal structures observed in the spectral core of the Ca II H line are ephemeral visuals caused by the shock dynamics of more stable…

Solar and Stellar Astrophysics · Physics 2015-02-11 V. M. J. Henriques , E. Scullion , M. Mathioudakis , D. Kiselman , P. T. Gallagher , F. P. Keenan

The Interferometric Bidimensional Spectrometer (IBIS) installed at the Dunn Solar Telescope of the NSO/SP is used to investigate the morphology and dynamics of the lower chromosphere and the virtually non-magnetic fluctosphere below. The…

Solar and Stellar Astrophysics · Physics 2014-11-20 F. Wöger , S. Wedemeyer-Böhm , H. Uitenbroek , T. R. Rimmele

We determine magnetic fields from the photosphere to the upper chromosphere combining data from the Hinode satellite and the CLASP2.1 sounding rocket experiment. CLASP2.1 provided polarization profiles of the Mg~{|sc ii} $h$ and $k$ lines,…

The strongly coupled hydrodynamic, magnetic, and radiation properties of the plasma in the solar chromosphere makes it a region of the Sun's atmosphere that is poorly understood. We use data obtained with the high-resolution Visible…

We recently reported extremely rapid changes in chromospheric fine structure observed using the IBIS instrument in the red wing of H alpha. Here, we examine data obtained during the same observing run (August 7 2010), of a mature active…

Solar and Stellar Astrophysics · Physics 2015-06-18 Isabel Lipartito , Philip Judge , Kevin Reardon , Gianna Cauzzi

We characterize waves in small magnetic elements and investigate their propagation in the lower solar atmosphere from observations at high spatial and temporal resolution. We use the wavelet transform to analyze oscillations of both…

Solar and Stellar Astrophysics · Physics 2017-03-31 Shahin Jafarzadeh , S. K. Solanki , M. Stangalini , O. Steiner , R. H. Cameron , S. Danilovic

The solar chromosphere is a vigorously dynamic region of the sun, where waves and magnetic fields play an important role. To improve chromospheric diagnostics, we present new observations in Ca II 8542 carried out with the SST/CRISP on La…

Solar and Stellar Astrophysics · Physics 2015-03-14 Jaime de la Cruz Rodríguez , Hector Socas-Navarro , Michiel van Noort , Luc Rouppe van der Voort

Simultaneous measurement of line-of-sight (LOS) magnetic and velocity fields at the photosphere and chromosphere are presented. Fe I line at $\lambda6569$ and $H_{\alpha}$ at $\lambda6563$ are used respectively for deriving the physical…

Astrophysics · Physics 2009-11-13 K. Nagaraju , K. Sankarasubramanian , K. E. Rangarajan
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