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Related papers: Dynamic fibrils in H-alpha and C IV

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We present a statistical study of chromospheric evaporation in solar flares using simultaneous observations by the RHESSI X-ray telescope and the IRIS UV spectrograph. The results are compared with radiation hydrodynamic flare models from…

Solar and Stellar Astrophysics · Physics 2019-01-23 Viacheslav M Sadykov , Alexander G Kosovichev , Ivan N Sharykin , Graham S Kerr

Solar jets, collimated plasma ejections driven by magnetic reconnection, play a vital role in energy transport and coronal heating. While rotational motions in jets are often attributed to magnetic field untwisting, alternative explanatory…

Solar and Stellar Astrophysics · Physics 2026-02-25 Lei Huang , Yang Guo , Zhen Li , Jinhan Guo , Mingde Ding

We present a study of the temporal evolution of coronal loops in active regions and its implications for the dynamics in coronal loops. We analyzed images of the Atmospheric Imaging Assembly (AIA) on the Solar Dynamics Observatory (SDO) at…

Solar and Stellar Astrophysics · Physics 2011-08-09 S. Kamio , H. Peter , W. Curdt , S. K. Solanki

We present a detailed analysis of time variability of two distinct C IV broad absorption line (BAL) components seen in the spectrum of J162122.54+075808.4 ($z_{em}$ = 2.1394) using observations from SDSS, NTT and SALT taken at seven…

Astrophysics of Galaxies · Physics 2021-05-12 P. Aromal , R. Srianand , P. Petitjean

Observational evidence for gentle chromospheric evaporation during the impulsive phase of a C9.1 solar flare is presented using data from the Reuven Ramaty High-Energy Solar Spectroscopic Imager and the Coronal Diagnostic Spectrometer on…

It remains unclear which physical processes are responsible for the dramatic increase with height of the temperature in stellar atmospheres, known as the chromospheric ($\sim$10,000 K) and coronal (several million K) heating problems.…

Solar and Stellar Astrophysics · Physics 2022-11-17 Souvik Bose , Bart De Pontieu , Viggo Hansteen , Alberto Sainz Dalda , Sabrina Savage , Amy Winebarger

Solar jets are collimated plasma ejections along magnetic field lines observed in hot (EUV jets) and cool (chromospheric surges) temperature diagnostics. Their trigger mechanisms and the relationship between hot and cool jets are still not…

We study a series of X-ray-bright, rapidly-evolving active-region coronal jets outside the leading sunspot of AR 12259, using Hinode/XRT, SDO/AIA and HMI, and IRIS data. The detailed evolution of such rapidly evolving "violent" jets…

Solar and Stellar Astrophysics · Physics 2017-07-26 Alphonse C. Sterling , Ronald L. Moore , David A. Falconer , Navdeep K. Panesar , Francisco Martinez

The emergence of active regions (ARs) leads to various dynamic activities. Using high-resolution and long-lasting H$\alpha$ observations from the New Vacuum Solar Telescope, we report the dynamics of NOAA AR 12700 in its emerging phase on…

Solar and Stellar Astrophysics · Physics 2019-09-06 Sihui Zhong , Yijun Hou , Jun Zhang

Flares are known to restructure the magnetic field in the corona and to accelerate the gas between the field lines, but their effect on the photosphere is less well studied. New data of the Solar Optical Telescope (SOT) onboard Hinode…

Solar and Stellar Astrophysics · Physics 2010-07-02 Jun Zhang , Leping Li , S. K. Solanki

We have analyzed H-alpha intensity images obtained at a 1 minute cadence with the Global Oscillation Network Group (GONG) system to investigate the properties of oscillations in the 0-8 mHz frequency band at the location and time of strong…

Solar and Stellar Astrophysics · Physics 2018-03-08 Teresa Monsue , Frank Hill , Keivan G. Stassun

We use X-ray observations of the nearby binaries 61 Cyg A/B (K5V and K7V) and Alpha Cen A/B (G2V and K1V) to study the long-term evolution of magnetic activity in weakly to moderately active G + K dwarfs over nearly a decade. Specifically…

Solar and Stellar Astrophysics · Physics 2015-06-05 J. Robrade , J. H. M. M. Schmitt , F. Favata

Oscillations of coronal loops in the Sun have been reported in both imaging and spectral observations at the onset of flares. Images reveal transverse oscillations, whereas spectra detect line-of-sight velocity or Doppler-shift…

Solar and Stellar Astrophysics · Physics 2015-05-27 Danica Tothova , Davina Innes , Guillermo Stenborg

We report on the Atmospheric Imaging Assembly (AIA) observations of plasma outflows originating in a coronal dimming during the 2015 April 28th filament eruption. After the filament started to erupt, two flare ribbons formed, one of which…

Solar and Stellar Astrophysics · Physics 2021-01-20 Juraj Lörinčík , Jaroslav Dudík , Guillaume Aulanier , Brigitte Schmieder , Leon Golub

High-resolution imaging observations from the Hinode spacecraft in the CaII H line are employed to study the dynamics of the chromosphere above a sunspot. We find that umbral flashes and other brightenings produced by the oscillation are…

Astrophysics · Physics 2011-02-11 H. Socas-Navarro , S. W. McIntosh , R. Centeno , A. G. de Wijn , B. W. Lites

Coronal waves, significant solar phenomena, act as diagnostic tools for scientists studying solar atmosphere properties. Here, we present a novel observation detailing how a coronal wave event, associated with an X5.0 class flare,…

While previous work explored the fractality and self-organized criticality (SOC) of flares and nanoflares in wavelengths emitted in the solar corona (such as in hard X-rays, soft X-rays, and EUV wavelenghts), we focus here on impulsive…

Solar and Stellar Astrophysics · Physics 2022-07-27 Markus J. Aschwanden , Nived Vilangot Nhalil

High-resolution broadband filtergrams of active region NOAA 11271 in Ca ii H and G band were obtained with the Solar Optical Telescope on board Hinode to identify the physical driver responsible for the dynamic and small-scale chromospheric…

Solar and Stellar Astrophysics · Physics 2015-06-19 Rohan E. Louis , Christian Beck , Kiyoshi Ichimoto

Coronal dimmings are transient depletions of coronal plasma observed in extreme ultraviolet and soft X-rays, interpreted as low-corona signatures of coronal mass ejections (CMEs). Their evolution is closely linked to CME dynamics, flare…

Solar and Stellar Astrophysics · Physics 2026-03-26 Amaia Razquin , Karin Dissauer , Astrid M. Veronig , Graham Barnes

The origin of solar transition region redshifts is not completely understood. Current research is addressing this issue by investigating three-dimensional magneto-hydrodynamic models that extend from the photosphere to the corona. By…

Solar and Stellar Astrophysics · Physics 2015-05-28 Pia Zacharias , Sven Bingert , Hardi Peter
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