Related papers: The Solar Flare Iron Abundance
In previous works we have developed a method to convert solar X-ray data, collected with the Yohkoh/SXT, into templates of stellar coronal observations. Here we apply the method to several solar flares, for comparison with stellar X-ray…
The first simultaneous observations of the Fe XVIII 974.86 {\AA} and Fe XX 721.56 {\AA} forbidden lines from the Spectral Imaging of the Coronal Environment (SPICE) spectrograph on Solar Orbiter are presented. The lines were observed from…
In a solar flare, a large fraction of the magnetic energy released is converted rapidly to the kinetic energy of non-thermal particles and bulk plasma motion. This will likely result in non-equilibrium particle distributions and turbulent…
We report high-resolution observations at mid-infrared wavelengths of a minor solar flare, SOL2014-09-24T17T17:50 (C7.0), using Quantum Well Infrared Photodetector (QWIP) cameras at an auxiliary of the McMath-Pierce telescope. The flare…
HARPS-N spectra with S/N > 250 and MARCS model atmospheres were used to derive abundances of C, O, Na, Mg, Al, Si, Ca, Ti, Cr, Fe, Ni, Zn, and Y in ten stars from the Kepler LEGACY sample (including the binary pair 16 Cyg A and B) selected…
This study introduces a line list for the abundance analysis of F and G type stars across the 4080-9675 A wavelength range. A systematic search employing lower excitation potentials, accurate log gf values, and an updated multiplet table…
The solar photospheric oxygen abundance has been determined from [OI], OI, OH vibration-rotation and OH pure rotation lines by means of a realistic time-dependent, 3D, hydrodynamical model of the solar atmosphere. In the case of the OI…
We have measured phosphorus abundances in nine disk stars between -1 $<$ [Fe/H] $<$ -0.5 and in 12 members of the Hyades open cluster using two P I lines at 1.06 $\mu$m. High resolution infrared spectra were obtained using Phoenix on Gemini…
We searched for superflares on solar-type stars using Kepler data with 1 min sampling in order to detect superflares with short duration. We found 187 superflares on 23 solar-type stars whose bolometric energy ranges from the order of…
Solar flares involve impulsive energy release, which results in enhanced radiation over a broad spectral range and a wide range of heights. In particular, line emission from the chromosphere can provide critical diagnostics of plasma…
We studied the thermal properties and chemical composition of the X-ray emitting plasma of a sample of bright members of the Taurus Molecular Cloud to investigate possible differences among classical and weak-lined T Tauri stars and…
We report X-ray spectroscopic results for four giant solar flares occurred on 2005 September 7 (X17.0), 2005 September 8 (X5.4), 2005 September 9 (X6.2), and 2006 December 5 (X9.0), obtained from Earth albedo data with the X-ray imaging…
Abundances of five elements, Na, Mg, Al, Si, and Sr, are investigated for 44 very metal-poor stars (-4.0 < [Fe/H] < -1.5) in the Galactic halo system based on an Local Thermodinamic Equilibrium (LTE) analysis of high-resolution…
The X-shooter Spectral Library (XSL) is a large empirical stellar library used as a benchmark for the development of stellar population models. The inclusion of $\alpha$-elements abundances is crucial to disentangling the chemical evolution…
The first measurement of the photospheric abundances in a star at the Galactic Center are presented. A detailed abundance analysis of the Galactic Center M2 supergiant IRS 7 was carried out using high-resolution near-infrared echelle…
We obtained optical and near-infrared spectra of Type$\,$Ia supernovae (SNe$\,$Ia) at epochs ranging from 224 to 496 days after the explosion. The spectra show emission lines from forbidden transitions of singly ionised iron and cobalt…
Thermal conductivity of the most abundant element in the planetary core, Iron (Fe) is measured up to Earth's outer core pressure $\sim 120$ GPa. The measurements are carried out using the laser heated diamond anvil cell facility, where the…
We present a spectroscopic study of the inner circumstellar ring around SN 1987A. The aim is to determine the elemental abundances and density structure, with particular emphasis on the abundance of iron. We acquired and analysed optical…
In the present paper, we analyze three energetic X-ray flares from the active RS CVn binary HR 1099 using data obtained from XMM-Newton. The flare duration ranges from 2.8 to 4.1 h, with e-folding rise and decay times in the range of 27 to…
I report on the high resolution spectra of the remarkable X9 solar flare of 2024 Oct 03 (SOL2024-10-03T12:08) and evaluate the extent to which nonthermal electron beams that generate dense chromospheric condensations can power very bright…