Related papers: Modeling Flare Continuum Emission Observed by Hino…
We present the results of a direct measurement of the cosmic-ray helium spectrum with the CALET instrument in operation on the International Space Station since 2015. The observation period covered by this analysis spans from October 13,…
The intensity of the \oiv~2s$^{2}$ 2p $^{2}$P-2s2p$^{2}$ $^{4}$P and \siv~3 s$^{2}$ 3p $^{2}$P- 3s 3p$^{2}$ $^{4}$ P intercombination lines around 1400~\AA~observed with the \textit{Interface Region Imaging Spectrograph} (IRIS) provide a…
The recent analysis of observations taken with the EIS instrument on Hinode suggests that well constrained measurements of the temperature distribution in solar active regions can finally be made. Such measurements are critical for…
We present observations of a B7.9-class flare that occurred on the 24th January, 2015, using the Atmopsheric Imaging Assembly (AIA) of the Solar Dynamics Observatory (SDO), the EUV Imaging Spectrometer (EIS) and the X-Ray Telescope of…
This paper presents measurements of the energy radiated by the lower solar atmosphere, at optical, UV, and EUV wavelengths, during an X-class solar flare (SOL2011-02-15T01:56) in response to an injection of energy assumed to be in the form…
Deriving a well-constrained differential emission measure (DEM) distribution for solar flares has historically been difficult, primarily because no single instrument is sensitive to the full range of coronal temperatures observed in flares,…
We report multi-wavelength ultraviolet observations taken with the IRIS satellite, concerning the emergence phase in the upper chromosphere and transition region of an emerging flux region (EFR) embedded in the pre-existing field of active…
The Extreme ultraviolet Imaging Spectrometer (EIS) on board the Hinode spacecraft has been operating since 2006, returning high resolution data in the 170-212 and 246-292 A wavelength regions. EIS has four slit options, with the narrow 1"…
Increase in the Balmer continuum radiation during solar flares was predicted by various authors but never firmly confirmed observationally using ground-based slit spectrographs. Here we describe a new post-focal instrument - Image Selector…
The abundances of low First Ionisation Potential (FIP) elements are three to four times higher (FIP bias) in the closed loop active corona than in the photosphere, known as the FIP effect. Observations suggest that the abundances vary in…
The extreme ultraviolet (EUV) and X-ray radiation emitted during solar flares has been shown to significantly increase the electron density of the Earth's ionosphere. During flares, quasi-periodic pulsations (QPPs) in X-ray flux originating…
The GOES X1 flare SOL2014-10-25T17:08:00 was a three-ribbon solar flare observed with IRIS in the near and far ultraviolet. One of the flare ribbons crossed a sunspot umbra, producing a dramatic, $\sim1000$% increase in the near-ultraviolet…
In the present work we study Hinode/EIS observations of an active region taken before, during and after a small C2.0 flare in order to monitor the evolution of the magnetic field evolution and its relation to the flare event. We find that…
We study the coronal dimming caused by the fast halo CME (deprojected speed v =1250 km s $^{-1})$ associated with the C3.7 two-ribbon flare on 2012 September 27, using Hinode/EIS spectroscopy and SDO/AIA Differential Emission Measure (DEM)…
We present a study of a recurring jet observed on October 31, 2011 by SDO/AIA, Hinode/XRT and Hinode/EIS. We discuss the physical parameters of the jet such as density, differential emission measure, peak temperature, velocity and filling…
White-light emissions were observed from an X1.7 class solar flare on 27 January 2012, using three continuum bands (red, green, and blue) of the Solar Optical Telescope (SOT) onboard the Hinode satellite. This event occurred near the solar…
The excess broadening of high-temperature spectral lines, long observed near the tops of flare arcades, is widely considered to result from magnetohydrodynamic (MHD) turbulence. According to different theories, plasma turbulence is also…
Recent observations from the Extreme-ultraviolet Imaging Spectrometer (EIS) on board Hinode have shown that low density areas on the periphery of active regions are characterized by strong blue-shifts at 1 MK. These Doppler shifts have been…
Context: Flare kernels brighten simultaneously in all SDO/AIA channels making it difficult to determine their temperature structure. IRIS is able to spectrally resolve Fe xxi emission from cold chromospheric brightenings, so can be used to…
Spectroscopic observations of prominence eruptions associated with coronal mass ejections (CMEs), although relatively rare, can provide valuable plasma and 3D geometry diagnostics. We report the first observations by the Interface Region…