Related papers: High-frequency spicule oscillations generated via …
Although it is well known that the solar acoustic mode frequency increases as the solar activity increases, the mechanism behind it is still unknown. Mode frequencies with 20 < l < 900 obtained by applying spherical harmonic decomposition…
Solar oscillations frequencies show a distinct change with solar activity. The changes in frequencies can be used to study the time variation of solar structure. We discuss constraints on the changes in solar structure with time as obtained…
We present observations of persistent oscillations of some bright features in the upper-chromosphere/transition-region above sunspots taken by IRIS SJ 1400 {\AA} and upward propagating quasi-periodic disturbances along coronal loops rooted…
Chromospheric wave activity around flares and filaments has been a research focus for years, and could provide indirect measurements of local conditions that are not otherwise accessible. One interesting observed phenomenon is oscillations…
The integrated brightness of the Sun shows variability on time-scales from minutes to decades. This variability is mainly caused by pressure mode oscillations, by granulation and by dark spots and bright faculae on the surface of the Sun.…
We reexamine the production of gravitational waves by bubble collisions during a first-order phase transition. The spectrum of the gravitational radiation is determined by numerical simulations using the "envelope approximation". We find…
Alfvenic waves are thought to play an important role in coronal heating and solar wind acceleration. Recent observations by Hinode/SOT showed that the spicules mostly exhibit upward propagating high frequency waves. Here we investigate the…
This work aims to understand the behavior of non-linear waves in the vicinity of a coronal null point. In previous works we have showed that high frequency waves are generated in such magnetic configuration. This paper studies those waves…
We have used available intermediate degree p-mode frequencies for the solar cycle 23 to check the validity of previously derived empirical relations for frequency shifts (Jain et al.: 2000, Solar Phys., 192, 487). We find that the…
Oscillatory signals from coherently excited phonons are regularly observed in ultrafast pump-probe experiments on condensed matter samples. Electron-phonon coupling implies that coherent phonons also modulate the electronic band structure.…
We present the results of numerical simulations of wave propagation and jet formation in solar atmosphere models with different magnetic field configurations. The presence in the chromosphere of waves with periods longer than the acoustic…
High-speed downflows have been observed in the solar transition region (TR) and lower corona for many decades. Despite their abundance, it has been hard to find signatures of such downflows in the solar chromosphere. In this work, we target…
A first-principle study of the collective oscillation spectrum of a strongly correlated one-component plasma in a strong magnetic field is presented. The spectrum consists of six fundamental modes which are found to be in good agreement…
We present a formalism for investigating the interaction between pmode oscillations and convection by analyzing realistic, three-dimensional simulations of the near-surface layers of the solar convection zone. By choosing suitable…
We study the nature of quiet-Sun oscillations using multi-wavelength observations from TRACE, Hinode, and SOHO. The aim is to investigate the existence of propagating waves in the solar chromosphere and the transition region via analyzing…
Two sequences of solar images obtained by the Transition Region and Coronal Explorer in three UV passbands are studied using wavelet and Fourier analysis and compared to the photospheric magnetic flux measured by the Michelson Doppler…
Analysis of over 36 years of time series data from the NSO/AFRL/Sac Peak K-line monitoring program elucidates five components of the variation of the seven measured chromospheric parameters: (a) the solar cycle (period ~ 11 years), (b)…
During the total solar eclipse of 11 July 2010, multi-slit spectroscopic observations of the solar corona were performed from Easter Island, Chile. To search for high-frequency waves, observations were taken at a high cadence in the green…
We report three-minute oscillations in the solar chromosphere driven by a strong downflow event in a sunspot. We used the Fast Imaging Solar Spectrograph of the 1.6 m New Solar Telescope and the Interface Region Imaging Spectrograph (IRIS).…
Time varying media recently emerged as promising candidates to fulfill the dream of controlling the wave frequency without nonlinear effects. However, frequency conversion remains limited by the dynamics of the variations of the propagation…