相关论文: Oscillatory Response of the Solar Chromosphere to …
We detect rapid downflows of 150-217 km/s in IRIS Si IV 1402.77 nm measurements of an X9-class solar flare on 2024 October 3rd. The fast redshift values persist for over 15 minutes from flare onset, and can be split into two distinct stages…
High-resolution imaging observations from the Hinode spacecraft in the CaII H line are employed to study the dynamics of the chromosphere above a sunspot. We find that umbral flashes and other brightenings produced by the oscillation are…
Oscillations in sunspot umbrae exhibit remarkable differences between the photosphere and chromosphere. We evaluate two competing scenarios proposed for explaining those observations: a chromospheric resonant cavity and waves traveling from…
We observed quiescent coronal loops using multi-wavelength observations from the Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory (SDO) on 2016 April 13. The flows at the footpoints of such loop systems are studied…
Solar pores are strongly magnetized regions lacking a photospheric penumbra and characterized by predominantly vertical magnetic fields. We present a multi-line study of flashes in a solar pore using high-resolution observations from the…
The Visible Spectro-Polarimeter (ViSP) of the NSF Daniel K. Inouye Solar Telescope (DKIST) collected its Science Verification data on May 7-8, 2021. The instrument observed multiple layers of a sunspot atmosphere simultaneously, in…
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,…
The acoustic resonator is an important model for explaining the three-minute oscillations in the chromosphere above sunspot umbrae. The steep temperature gradients at the photosphere and transition region provide the cavity for the acoustic…
In this paper, we report our multiwavelength observations of the large-amplitude longitudinal oscillations of a filament on 2015 May 3. Located next to active region 12335, the sigmoidal filament was observed by the ground-based H$\alpha$…
We analyse sunspot oscillations using Interface Region Imaging Spectrograph (IRIS) slit-jaw and spectral data and narrow-band chromospheric images from the New Solar Telescope (NST) for the main sunspot in NOAA AR 11836. We report that the…
Plasma loops or plumes rooted in sunspot umbrae often harbor downflows with speeds of 100 km/s. These downflows are supersonic at transition region temperatures of 0.1 MK. The source of these flows is not well understood. We aim to…
The origin of the slow solar wind is still an open issue. One possibility that has been suggested is that upflows at the edge of an active region can contribute to the slow solar wind. We aim to explain how the plasma upflows are generated,…
Observational evidence for gentle chromospheric evaporation during the impulsive phase of a C9.1 solar flare is presented using data from the Reuven Ramaty High-Energy Solar Spectroscopic Imager and the Coronal Diagnostic Spectrometer on…
We present a study of wave processes occurring in solar active region NOAA 11131 on 2010 December 10, captured by the Solar Dynamics Observatory in the 1600A, 304A, and 171A channels. For spectral analysis we employed pixelised wavelet…
We report spectropolarimetric observations of a supersonic downflow impacting the lower atmosphere within a large sunspot umbra. This work is an extension of Schad et al. 2016 using observations acquired in the He I 10830 Angstrom triplet…
This paper reports the results of a survey of Doppler shift oscillations measured during solar flares in emission lines of S XV and Ca XIX with the Bragg Crystal Spectrometer (BCS) on Yohkoh. Data from 20 flares that show oscillatory…
Recent progress in instrumentation enables solar observations with high resolution simultaneously in the spatial, temporal, and spectral domains. We use such high-resolution observations to study small-scale structures and dynamics in the…
Context. The height structure of 3-min oscillations over sunspots is studied in the context of the recently discovered effect of height inversion: over the umbra, the spatial location of the maximum of chromospheric 3-min oscillation power…
We report the discovery of supersonic downflows in a sunspot light bridge using measurements taken with the spectropolarimeter on board the Hinode satellite. The downflows occur in small patches close to regions where the vector magnetic…
We report a different type of three-minute chromospheric oscillations above a sunspot in association with a small-scale impulsive event in a light bridge. During our observations, we found a transient brightening in the light bridge. The…