English
Related papers

Related papers: Umbral oscillations in the photosphere. A comprehe…

200 papers

Small-scale magnetic field concentrations (magnetic elements) in the quiet Sun are believed to contribute to the energy budget of the upper layers of the Sun's atmosphere, as they are observed to support a large number of MHD modes. In…

Solar and Stellar Astrophysics · Physics 2015-04-29 M. Stangalini , F. Giannattasio , S. Jafarzadeh

In the immediate sunspots' vicinity -- their superpenumbra -- 3-minute line-of-sight (LOS) velocity oscillations dominate in the photosphere and chromosphere. Oscillations of similar periods are also registered in the transition region and…

Solar and Stellar Astrophysics · Physics 2024-09-25 Andrei Chelpanov , Nikolai Kobanov

The continuous high spatial-resolution Doppler observation of the Sun by Solar Dynamics Observatory / Helioseismic and Magnetic Imager allows us to compute helioseismic k-omega power-spectrum diagram using only oscillations inside a…

Solar and Stellar Astrophysics · Physics 2015-06-11 Junwei Zhao , Dean-Yi Chou

We show that under certain conditions, subsurface structures in the solar interior can alter the average acoustic power observed at the photosphere above them. By using numerical simulations of wave propagation, we show that this effect is…

Solar and Stellar Astrophysics · Physics 2015-05-18 Thomas Hartlep , Alexander G. Kosovichev , Junwei Zhao , Nagi N. Mansour

Observations of quiet Sun from the Solar Optical Telescope/Spectro-Polarimeter (SOT/SP) aboard the Hinode spacecraft would reveal the magnetic characters of the solar photosphere. By making use of the deep mode observations of three quiet…

Astrophysics · Physics 2008-12-18 Chunlan Jin , Jingxiu Wang , Meng Zhao

The internal dynamics of the Sun generate magnetic and plasma structures in the photosphere and overlying atmosphere across a wide range of spatial scales. Identifying the critical spatial scale is essential for interpreting physical…

Solar and Stellar Astrophysics · Physics 2026-04-14 Ananya Hore , Prantika Bhowmik

The emergence of the magnetic field through the photosphere has multiple manifestations and sunspots are the most prominent examples of this. One of the most relevant sunspot properties, to study both its structure and evolution, is the…

Solar and Stellar Astrophysics · Physics 2012-11-30 R. Gafeira , C. C. Fonte , M. A. Pais , J. Fernandes

Magnetohydrodynamic (MHD) waves have been considered as energy sources for heating the solar chromosphere and the corona. Although MHD waves have been observed in the solar atmosphere, there are a lack of quantitative estimates on the…

Solar and Stellar Astrophysics · Physics 2016-11-01 Ryuichi Kanoh , Toshifumi Shimizu , Shinsuke Imada

Popular scientific summary -- The atmosphere of the Sun is envisioned as composed of inherently complex, non-homogeneous, and dynamic layers. A detailed understanding of the physical processes involved in these layers is still lacking. For…

Solar and Stellar Astrophysics · Physics 2021-10-22 Souvik Bose

Sunspots are prominent manifestations of solar magnetoconvection and imaging their subsurface structure is an outstanding problem of wide physical importance. Travel times of seismic waves that propagate through these structures are…

Solar and Stellar Astrophysics · Physics 2015-06-05 Shravan Hanasoge , Aaron Birch , Laurent Gizon , Jeroen Tromp

The observed splittings of solar oscillation frequencies can be employed to separate the effects of internal solar rotation and to estimate the contribution from a large-scale magnetic field or any latitude-dependent thermal perturbation…

Astrophysics · Physics 2007-05-23 H. M. Antia , S. M. Chitre , M. J. Thompson

A number of recent investigations have revealed that transverse waves are ubiquitous in the solar chromosphere. The vast majority of these have been reported in limb spicules and active region fibrils. We investigate long-lived, quiet Sun,…

Solar and Stellar Astrophysics · Physics 2015-06-04 D. Kuridze , R. J. Morton , R. Erdélyi , G. D. Dorrian , M. Mathioudakis , D. B. Jess , F. P. Keenan

The driving and excitation mechanisms of decay-less kink oscillations in coronal loops remain under debate. We aim to quantify and provide simple observational constraints on the photospheric driving of oscillating coronal loops in a few…

Waves are thought to play a significant role in the heating of the solar atmosphere and the acceleration of the wind. Among the many types of waves observed in the Sun, the so-called p-modes with a 3 mHz frequency peak dominate the lower…

We analysed line-of-sight magnetic fields and magnetic power spectra of an undisturbed photosphere using magnetograms acquired by the Helioseismic and Magnetic Imager (HMI) on-board the Solar Dynamic Observatory (SDO) and the Near InfraRed…

Solar and Stellar Astrophysics · Physics 2020-08-17 Valentina I. Abramenko , Vasyl B. Yurchyshyn

I report observations of unusually strong photospheric and chromospheric velocity oscillations in and near the leading sunspot of NOAA 10781 on 03 July 2005. I investigate an impinging wave as a possible origin of the velocity pattern, and…

Solar and Stellar Astrophysics · Physics 2015-03-17 C. Beck

Using SDO/HMI and SDO/AIA data for sunspot groups of the 24th solar cycle, we analyzed magnetic properties and He II 304 emission in leading and following sunspots separately. Simultaneous examination of umbral magnetic properties and…

Solar and Stellar Astrophysics · Physics 2015-11-24 Iu. S. Zagainova , V. G. Fainshtein , V. N. Obridko

We analyze the effect of a sunspot in its quiet surroundings applying a helioseismic technique on almost three years of Helioseismic and Magnetic Imager (HMI) observations obtained during solar cycle 24 to further study the sunspot…

Solar and Stellar Astrophysics · Physics 2018-05-23 M. Cristina Rabello-Soares , Richard S. Bogart , Philip H. Scherrer

Waves connect all the layers of the Sun, from its interior to the upper atmosphere. It is becoming clear now the important role of magnetic field on the wave propagation. Magnetic field modifies propagation speed of waves, thus affecting…

Astrophysics · Physics 2015-05-13 Elena Khomenko

Spectra of the cellular photospheric flows are determined from full-disk Doppler velocity observations acquired by the Helioseismic and Magnetic Imager (HMI) instrument on the Solar Dynamics Observatory (SDO) spacecraft. Three different…

Solar and Stellar Astrophysics · Physics 2015-10-01 David H. Hathaway , Thibaud Teil , Aimee A. Norton , Irina Kitiashvili