English
Related papers

Related papers: High-frequency Oscillations in Small Magnetic Elem…

200 papers

While the longitudinal field that dominates photospheric network regions has been studied extensively, small scale transverse fields have recently been found to be ubiquitous in the quiet internetwork photosphere. Few observations have…

The presence of magneto-acoustic waves in magnetic structures in the solar atmosphere is well-documented. Applying the technique of solar magneto-seismology (SMS) allows us to infer the background properties of these structures. Here, we…

Solar and Stellar Astrophysics · Physics 2016-01-27 N. Freij , I. Dorotovic , R. J. Morton , M. S. Ruderman , V. Karlovsky , R. Erdekyi

Observations carried out with the Magneto-Optical Filter at Two Heights (MOTH) experiment show upward-traveling wave packets in magnetic regions with frequencies below the acoustic cut-off. We demonstrate that the frequency dependence of…

Solar and Stellar Astrophysics · Physics 2010-01-28 M. Haberreiter , W. Finsterle

Improving methods for determining the subsurface structure of sunspots from their seismic signature requires a better understanding of the interaction of waves with magnetic field concentrations. We aim to quantify the impact of changes in…

Solar and Stellar Astrophysics · Physics 2017-08-30 T. Felipe , D. C. Braun , A. C. Birch

In sunspot umbrae, the core of some chromospheric lines exhibits periodic brightness enhancements known as umbral flashes. The consensus is that they are produced by the upward propagation of shock waves. This view has recently been…

A set of 464-min high-resolution high-cadence observations were acquired for a region near the Sun's disk center using the Interferometric BI-dimensional Spectrometer (IBIS) installed at the Dunn Solar Telescope. Ten sets of Dopplergrams…

Solar and Stellar Astrophysics · Physics 2022-05-24 Junwei Zhao , S. P. Rajaguru , Ruizhu Chen

We investigate the possibility of observing very small amplitude low frequency solar oscillations with the proposed laser interferometer space antenna LISA. For frequencies below $\sim 2\times 10^{-4}$ Hz the dominant contribution is from…

Astrophysics · Physics 2007-05-23 I. W. Roxburgh , A. G. Polnarev , G. Giampieri , S. V. Vorontsov

Acoustic waves are one of the primary suspects besides magnetic fields for the chromospheric heating process to temperatures above radiative equilibrium (RE). We derived the mechanical wave energy as seen in line-core velocities to obtain a…

Solar and Stellar Astrophysics · Physics 2015-05-13 C. Beck , E. Khomenko , R. Rezaei , M. Collados

The subject of this study is oscillations in the lower atmosphere in coronal-hole regions, where the conditions are favorable for propagation between the atmospheric layers. Based on spectroscopic observations in photospheric and…

Solar and Stellar Astrophysics · Physics 2021-12-22 Andrei Chelpanov , Nikolai Kobanov , Maksim Chelpanov , Aleksandr Kiselev

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

In the current analysis, we use spectroscopic observations of the quiet-Sun made by IRIS instrument, and investigate wave propagation. We analyze various spectral lines formed in different atmospheric layers such as the photosphere,…

Solar and Stellar Astrophysics · Physics 2024-03-18 Kartika Sangal , A. K. Srivastava , P. Kayshap , Ding Yuan , E. Scullion

The present study addresses the following questions: How representative of the actual velocities in the solar atmosphere are the Doppler shifts of spectral lines? How reliable is the velocity signal derived from narrowband filtergrams? How…

Solar and Stellar Astrophysics · Physics 2010-02-18 B. Fleck , T. Straus , M. Carlsson , S. M. Jefferies , G. Severino , T. D. Tarbell

Determination of the wave mode of short-wavelength electrostatic waves along with their generation mechanism requires reliable measurement of the wave electric field. We investigate the reliability of the electric field measurement for…

Space Physics · Physics 2023-05-03 Ahmad Lalti , Yuri V. Khotyaintsev , Daniel B. Graham

Context. MHD waves are proposed to transport sufficient energy from the photosphere to heat the transition-region (TR) and corona. However, various aspects of these waves such as their nature, propagation characteristics and role in the…

Solar and Stellar Astrophysics · Physics 2020-02-12 P. Kayshap , A. K. Srivastava , S. K. Tiwari , P. Jelinek , M. Mathioudakis

For the first time, we have determined the spatial distribution of magnetic waveguides and resonant cavities at different heights in the sunspot atmosphere. We applied a decomposition of time cubes of EUV/UV sunspot images obtained in the…

Solar and Stellar Astrophysics · Physics 2025-02-21 Robert Sych

We report and discuss phase-shift and phase travel time of low-frequency ({\nu} < 5.0 mHz) acoustic waves estimated within the photosphere and photosphere-chromosphere interface regions, utilizing multi-height velocities in the quiet Sun.…

Solar and Stellar Astrophysics · Physics 2024-07-01 Hirdesh Kumar , Brajesh Kumar , Shibu K. Mathew , A. Raja Bayanna , S. P. Rajaguru

A sunspot is an ideal waveguide for a variety of magnetohydrodynamic waves, which carry a significant amount of energy to the upper atmosphere and could be used as a tool to probe magnetic and thermal structure of a sunspot. In this study,…

Solar and Stellar Astrophysics · Physics 2020-09-02 Song Feng , Zheng Deng , Ding Yuan , Zhi Xu , Xiao Yang

The launch of the Hinode satellite has allowed for seeing-free observations at high-resolution and high-cadence making it well suited to study the dynamics of quiescent prominences. In recent years it has become clear that quiescent…

Solar and Stellar Astrophysics · Physics 2015-06-17 A. Hillier , R. J. Morton , R. Erdélyi

The investigation of plasma motions in the solar chromosphere is crucial for understanding the transport of mechanical energy from the interior of the Sun to the outer atmosphere and into interplanetary space. We report the finding of…

Solar and Stellar Astrophysics · Physics 2024-07-17 Jongchul Chae , Michiel van Noort , Maria S. Madjarska , Kyeore Lee , Juhyung Kang , Kyuhyoun Cho

We use images of high spatial and temporal resolution, obtained with the Rapid Oscillations in the Solar Atmosphere instrument at the Dunn Solar Telescope, to reveal how the generation of transverse waves in Type I spicules is a direct…

Solar and Stellar Astrophysics · Physics 2015-06-03 D. B. Jess , D. J. Pascoe , D. J. Christian , M. Mathioudakis , P. H. Keys , F. P. Keenan
‹ Prev 1 3 4 5 6 7 10 Next ›