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Related papers: Dynamics of the solar chromosphere. V. High-freque…

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We present evidence supporting wave reflection in the lower solar chromosphere based on helioseismic analysis of multi-height Doppler data. This evidence is derived through a wave propagation model that incorporates both upward- and…

Solar and Stellar Astrophysics · Physics 2024-03-29 Varun Chaturmutha , Bernhard Fleck , Stuart Jefferies

We assess broadband color filters for the two fast cameras on the PLAnetary Transits and Oscillations (PLATO) of stars space mission with respect to exoplanetary atmospheric characterization. We focus on Ultra Hot Jupiters and Hot Jupiters…

Earth and Planetary Astrophysics · Physics 2020-07-29 John Lee Grenfell , Mareike Godolt , Juan Cabrera , Ludmila Carone , Antonio Garcia Munoz , Daniel Kitzmann , Alexis Smith , Heike Rauer

The spatio-temporal dynamics of the solar photosphere is studied by performing a Proper Orthogonal Decomposition (POD) of line of sight velocity fields computed from high resolution data coming from the MDI/SOHO instrument. Using this…

Astrophysics · Physics 2009-11-13 A. Vecchio , V. Carbone , F. Lepreti , L. Primavera , L. Sorriso-Valvo , P. Veltri , G. Alfonsi , Th. Straus

We use Hinode/SOT Ca II H-line and blue continuum broadband observations to study the presence and power of high frequency acoustic waves at high spatial resolution. We find that there is no dominant power at small spatial scales; the…

Low amplitude is the defining characteristic of solar-like oscillations. The space projects $Kepler$ and $CoRoT$ give us a great opportunity to successfully detect such oscillations in numerous targets. Achievements of asteroseismology…

Solar and Stellar Astrophysics · Physics 2015-06-19 M. Yıldız , Z. Çelik Orhan , Ç. Aksoy , S. Ok

Spectroscopic observations at extreme and far ultraviolet wavelengths have revealed systematic upflows in the solar transition region and corona. These upflows are best seen in the network structures of the quiet Sun and coronal holes,…

Solar and Stellar Astrophysics · Physics 2021-03-17 Hui Tian , Louise Harra , Deborah Baker , David H. Brooks , Lidong Xia

We solve the problem of propagation and dissipation of Alfvenic turbulence in a model solar atmosphere consisting of a static photosphere and chromosphere, transition region, and open corona and solar wind, using a phenomenological model…

Astrophysics · Physics 2011-02-11 A. Verdini , M. Velli

Aims: To study the presence of superoscillations in coronal magnetoacoustic waves and its possible role in heating coronal loops through the strong and localized gradients they generate on the wave. Methods: An analytic model is built for…

Solar and Stellar Astrophysics · Physics 2018-07-04 A. López Ariste , M. Facchin

The presence of flare related acoustic emission (sunquakes) in some flares represents a severe challenge to our current understanding of flare energy transport processes. We present a comparison of new spectral observations from Hinode's…

Solar and Stellar Astrophysics · Physics 2015-10-14 Sarah A. Matthews , Louise K. Harra , Sergei Zharkov , Lucie M. Green

Context. An analysis of the oscillations above sunspots was carried out using simultaneous ground-based and Solar Dynamics Observatory (SDO) observations (SiI 10827A, HeI 10830A, FeI 6173A, 1700A, HeII 304A, FeIX 171A). Aims. Investigation…

Solar and Stellar Astrophysics · Physics 2014-11-25 N. I. Kobanov , A. A. Chelpanov , D. Y. Kolobov

Strong solar magnetic fields are the energy source of intense flares and energetic coronal mass ejections of space weather importance. The key issue is the difficulty in predicting the occurrence time and location of strong solar eruptions,…

Solar and Stellar Astrophysics · Physics 2023-07-04 P. K. Manoharan , C. J. Salter , S. M. White , P. Perillat , F. Fernandez , B. Perera , A. Venkataraman , C. Brum

The chromosphere of the quiet Sun is a highly intermittent and dynamic phenomenon. Three-dimensional radiation (magneto-)hydrodynamic simulations exhibit a mesh-like pattern of hot shock fronts and cool expanding post-shock regions in the…

Astrophysics · Physics 2009-11-13 Sven Wedemeyer-Böhm , Friedrich Wöger

Surges are cool and dense ejections typically observed in chromospheric lines and closely related to other solar phenomena like UV bursts or coronal jets. Our aim is to address the current lack of inverted models and diagnostics of surges…

Solar and Stellar Astrophysics · Physics 2021-11-10 D. Nóbrega Siverio , S. L. Guglielmino , A. Sainz Dalda

Registering periodic variations of spectral line widths serves as the main method for observing torsional Alfv\'{e}n waves. Theoretically, the method seems valid, yet it entails a number of caveats when applied to data. For instance, the…

Solar and Stellar Astrophysics · Physics 2022-12-29 A. A. Chelpanov , N. I. Kobanov

Observations of a large solar flare of December 13, 2006, using Solar Optical Telescope (SOT) on Hinode spacecraft revealed high-frequency oscillations excited by the flare in the sunspot chromosphere. These oscillations are observed in the…

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

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

We present a new method that combines the results of an oscillation study made in optical and radio observations. The optical spectral measurements in photospheric and chromospheric lines of the line-of-sight velocity were carried out at…

Solar and Stellar Astrophysics · Physics 2015-03-18 V. E. Abramov-Maximov , G. B. Gelfreikh , N. I. Kobanov , K. Shibasaki , S. A. Chupin

Context. The contribution of quiet-Sun regions to the solar irradiance variability is currently unclear. Some solar-cycle variations of the quiet-Sun physical structure, such as the temperature gradient, might affect the irradiance. The…

Solar and Stellar Astrophysics · Physics 2018-09-05 M. Faurobert , M. Carbillet , L. Marquis , A. Chiavassa , G. Ricort

Solar flare emission at X-ray and extreme ultraviolet (EUV) energies can cause substantial enhancements in the electron density in the Earth's lower ionosphere. It is now become clear that flares exhibit quasi-periodic pulsations with…

Acoustic and magnetoacoustic waves are among the possible candidate mechanisms that heat the upper layers of solar atmosphere. A weak chromospheric plage near a large solar pore NOAA 11005 was observed on October 15, 2008 in the lines Fe I…

Solar and Stellar Astrophysics · Physics 2016-07-27 M. Sobotka , P. Heinzel , M. Švanda , J. Jurčák , D. del Moro , F. Berrilli
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