Related papers: Nature of Quiet Sun Oscillations Using Data from t…
In this work we investigate the dynamic behavior of inter-network regions of the solar chromosphere. We observed the chromosphere of the quiet Sun using a narrow-band Lyot filter centered at the Ca II K 2v emission peak with a bandpass of…
We analyze and interpret SOHO/MDI data on oscillation frequency changes between 1996 and 2004 focusing on differences between activity minimum and maximum of solar cycle 23. We study only the behavior of the centroid frequencies, which…
Gravity waves are generated by turbulent subsurface convection overshooting or penetrating locally into a stably stratified medium. While propagating energy upwards, their characteristic negative phase shift over height is a well-recognized…
Torsional oscillations represent bands of fast and slow zonal flows around the Sun, which extend deep into the convection zone and migrate during solar cycles towards the equator following the sunspot butterfly diagram. Analysis of…
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 oscillations consist of a rich spectrum of internal acoustic waves and surface gravity waves, stochastically excited by turbulent convection. They have been monitored almost continuously over the last ten years with high-precision…
High-frequency waves (5 mHz to 20mHz) have previously been suggested as a source of energy accounting partial heating of the quiet solar atmosphere. The dynamics of previously detected high-frequency waves is analysed here. Image sequences…
It is well known that the dominant frequency of oscillations in the solar photosphere is $\approx$3 mHz, which is the result of global resonant modes pertaining to the whole stellar structure. However, analyses of the horizontal motions of…
The solar atmosphere is permeated by various types of waves that originate from subsurface convection. As these waves propagate upward, they encounter they encounter a steep decrease in the density of the medium, leading to their steepening…
Sunspots host a large variety of oscillatory phenomena, whose properties depend on the nature of the wave modes and the magnetic and thermodynamic structure of the spot. Umbral chromospheric oscillations exhibit significant differences…
Waves and oscillations have been observed in the Sun's atmosphere for over half a century. While such phenomena have readily been observed across the entire electromagnetic spectrum, spanning radio to gamma-ray sources, the underlying role…
We present a study of multi-wavelength observations, of a C 2.3 solar flare in Active Region NOAA 12353, observed on 2015 May 23, which reveal new properties of acoustic waves in the flaring region. The space-, and ground-based data…
Velocity oscillations in sunspot umbrae have been measured simultaneously in two spectral lines: the photospheric Silicon I 10827 A line and the chromospheric Helium I 10830 A multiplet. From the full Stokes inversion of temporal series of…
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…
We have measured the energy and dissipation of Alfvenic waves in the quiet Sun. A magnetic field was used to infer the location and orientation of the magnetic field lines along which the waves are expected to travel. The waves were…
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…
Quiet sun meterwave emission arises from thermal bremsstrahlung in the MK corona, and can potentially be a rich source of coronal diagnostics. On its way to the observer, it gets modified substantially due to the propagation effects -…
Coronal loop oscillations are common phenomena in the solar corona, which are often classified as decaying and decayless oscillations. Using the high-resolution observation measured by the Extreme Ultraviolet Imager (EUI) onboard the Solar…
We present properties of intensity oscillations of a sunspot in the photosphere and chromosphere using G~band and CaIIH filtergrams from Hinode. Intensity power maps as function of magnetic field strength and frequency reveal reduction of…
Although the magnetic fields in the quiet Sun account for the majority of the magnetic energy in the solar photosphere, inferring their exact spatial distribution, origin, and evolution poses an important challenge because the signals lie…