相关论文: Wave amplitude modulation in fan loops as observed…
We present an observational study of a quasi-periodic fast propagating (QFP) magnetosonic wave on 2012, April 23. The multiple wave trains were observed along an active region open loop system which has a divergence geometry. The wave…
The extended solar corona at 10-30 solar radii is essentially devoid of all waves below 100 kHz other than triggered ion acoustic waves (TIAW), which consist of a low frequency electromagnetic wave at a frequency of a few Hz coupled to one…
This short review paper gives an overview of recently observed transverse, propagating velocity perturbations in coronal loops. These ubiquitous perturbations are observed to undergo strong damping as they propagate. Using 3D numerical…
SDO/AIA images the full solar disk in several EUV bands that are each sensitive to coronal plasma emissions of one or more specific temperatures. We observe that when isolated active regions (ARs) are on the disk, full-disk images in some…
Aims. To study intensity oscillations in the solar chromosphere/corona above a quiet-Sun magnetic network. Methods. We analyse the time series of He II 256.32, Fe XI 188.23 and Fe XII 195.12 spectral lines observed by EUV Imaging…
Due to their characteristic temperature and density, loop structures in active regions (ARs) can be seen bright in extreme ultraviolet (EUV) and soft X-ray images. The semiempirical determination of the three-dimensional (3D) distribution…
We report a quasi-periodic pulsation (QPP) event simultaneously detected from the spatial displacements of coronal loop at both EUV images and microwave emission during the preflare phase of a C1.1 flare on 2016 March 23. Using the motion…
The recently released spacecraft potential measured by the RPW instrument on-board Solar Orbiter has been used to estimate the solar wind electron density in the inner heliosphere. Solar-wind electron density measured during June 2020 has…
We present observations of high temperature emission in the core of a solar active region using instruments on Hinode and SDO. These multi-instrument observations allow us to determine the distribution of plasma temperatures and follow the…
Recent observations have demonstrated that waves which are capable of carrying large amounts of energy are ubiquitous throughout the solar corona. However, the question of how this wave energy is dissipated (on which time and length scales)…
We search for signatures of high-frequency oscillations in the upper solar photosphere and low chromosphere in the context of acoustic heating of outer stellar atmospheres. We use ultraviolet image sequences of a quiet center-disk area from…
The rapid damping of slow magnetoacoustic waves in the solar corona has been extensively studied in previous years. Most studies suggest that thermal conduction is a dominant contributor to this damping, albeit with a few exceptions.…
We analyse intensity variations, as measured by the Atmospheric Imaging Assembly (AIA) in the 171 {\AA} passband, in two coronal loops embedded within a single coronal magnetic arcade. We detect oscillations in the fundamental mode with…
We present a study of the frequency of transient brightenings in the core of solar active regions as observed in the Fe XVIII line component of AIA/SDO 94 A filter images. The Fe XVIII emission is isolated using an empirical correction to…
Extracting the temperature of coronal loops is effective in the analysis of solar active region's loops and helps in better understanding of coronal events. To this end, various methods have already been developed like the method developed…
Solar intensity power spectra are usually characterised by coloured noise, with the spectral energy following a segmented power-law function of frequency, $S(f)\propto f^{-\alpha}$, over different frequency ranges. Typically, the power-law…
Waves are important for the heating of the solar corona and the acceleration of the solar wind. We have examined a long spectral time series of a southern coronal hole observed on the 25th February 1997, with the SUMER spectrometer on-board…
Following Couvidat (2013), we analyze data from the Helioseismic and Magnetic Imager (HMI) and the Atmospheric Imaging Assembly (AIA) instruments onboard the Solar Dynamics Observatory: Doppler velocity and continuum intensity at 6173 A as…
We study the acoustic properties of the solar chromosphere in the high-frequency regime using a time sequence of velocity measurements in the chromospheric Ca II 854.2 nm line taken with the Interferometric Bidimensional Spectrometer…
The spatio-temporal dynamics of the deformation of a vibrated plate is measured by a high speed Fourier transform profilometry technique. The space-time Fourier spectrum is analyzed. It displays a behavior consistent with the premises of…