English
Related papers

Related papers: Electron density diagnostic for hot plasmas in cor…

200 papers

Theoretical electron density-sensitive line ratios $R_1 - R_6$ of Ar XIV soft X-ray emission lines are presented. We found that these line ratios are sensitive to electron density $n_e$, and the ratio $R_1$ is insensitive to electron…

Plasma Physics · Physics 2007-05-23 G. Y. Liang , G. Zhao , J. L. Zeng , J. R. Shi

An analysis of $n=3 \to 2$ transition lines of carbon-like silicon reveals that some ratios of line intensities are sensitive to the electron density. The ratio between two group of $3d\to2p$ transition lines at 55.246 \AA and 55.346 \AA is…

Astrophysics · Physics 2008-11-26 Guiyun Liang , Gang Zhao

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…

Solar and Stellar Astrophysics · Physics 2016-10-19 V. Polito , G. Del Zanna , J. Dudík , H. E. Mason , A. Giunta , K. K. Reeves

Electron density diagnostics based on a line intensity ratio of Si X are applied to the X-ray spectra of Procyon, $\alpha$ Cen A$&$B, Capella and $\epsilon$ Eri measured with the Low Energy Transmission Grating Spectrometer (LETGS) combined…

Astrophysics · Physics 2008-11-26 G. Y. Liang , G. Zhao , J. R. Shi

We have used an electron beam ion trap to measure electron-density-diagnostic line-intensity ratios for extreme ultraviolet lines from F XII, XIII, and XIV at wavelengths of 185-205 255-276 Angstroms. These ratios can be used as density…

Accurate measurements of electron density are critical for determination of the plasma properties in the solar corona. We compare the electron densities diagnosed from Fe XIII lines observed by the Extreme-Ultraviolet Imaging Spectrometer…

We provide a discussion of the density and photoexcitation sensitivity of the X-ray spectra of Fe L-shell ions (Fe XVII-Fe XXIV) calculated with the Livermore X-ray Spectral Synthesizer, a suite of IDL codes that calculates spectral models…

Astrophysics · Physics 2009-11-10 Christopher W. Mauche , Duane A. Liedahl , Kevin B. Fournier

Effects of radio-frequency power and driven frequency on the two-dimensional (axial and radial) distributions of electron density and temperature were experimentally investigated in low pressure capacitively coupled argon plasmas. The…

Plasma Physics · Physics 2020-10-22 Jidun Wu , Hao Zheng , Yanfei Wang , Fengzhu Zhou , Xiaojiang Huang

An electron beam ion trap (EBIT) is used to measure extreme ultraviolet spectra between 10 nm and 25 nm from highly-charged ions of tungsten with an open 3d shell (W XLVIII through W LVI). We found that almost all strong lines are due to…

Atomic Physics · Physics 2013-10-15 Yu. Ralchenko , I. N. Draganić , D. Osin , J. D. Gillaspy , J. Reader

Efforts to benchmark astrophysical observations with X-ray laboratory measurements have been stymied by observed and measured differences of up to a factor of two in the ratio '3s/3d' of Fe XVII lines at ~17 \AA and ~15 \AA respectively.…

Astrophysics · Physics 2007-05-23 Guo-Xin Chen , Anil K. Pradhan

Recent state-of-the-art calculations of A-values and electron impact excitation rates for Fe III are used in conjunction with the Cloudy modeling code to derive emission line intensity ratios for optical transitions among the fine-structure…

We review the accuracy of existing \ion{Fe}{17} X-ray line emission models by comparing them with an extensive analysis of \textit{Chandra} high energy transmission grating (HETG) observations of stellar coronae. We find significant…

Solar and Stellar Astrophysics · Physics 2009-05-06 M. F. Gu

High resolution spectra of the active binary Capella (G8 III + G1 III) covering the energy range 0.4-8.0 keV (1.5-30 Angstroms) show a large number of emission lines, demonstrating the performance of the HETGS. A preliminary application of…

Rich soft X-ray emission lines of highly charged silicon ions (Si VI--Si XII) were observed by irradiating an ultra-intense laser pulse with width of 200 fs and energy of $\sim$90 mJ on the solid silicon target. The high resolution spectra…

Astrophysics · Physics 2009-11-13 G. Y. Liang , G. Zhao , J. Y. Zhong , Y. T. Li , Y. Q. Liu , Q. L. Dong , X. H. Yuan , Z. Jin , J. Zhang

New laboratory measurements using an Electron Beam Ion Trap (EBIT) and an x-ray microcalorimeter are presented for the n=3 to n=2 Fe XVII emission lines in the 15 {\AA} to 17 {\AA} range, along with new theoretical predictions for a variety…

Instrumentation and Methods for Astrophysics · Physics 2011-06-15 J. D. Gillaspy , T. Lin , L. Tedesco , J. N. Tan , J. M. Pomeroy , J. M. Laming , N. Brickhouse , G. -X. Chen , E. Silver

After an extensive assessment of the effective collision strengths available to model the He-like triplet of C V, N VI, O VII, Ne IX, Mg XI and Si XIII in collisionally dominated plasmas, new accurate effective collision strengths are…

Instrumentation and Methods for Astrophysics · Physics 2016-07-27 Y. Rodríguez , E. Gatuzz , M. A. Bautista , C. Mendoza

Context: The sharp temperature and density gradients in the coronal transition region are a challenge for models and observations. Aims: We set out to get linearly- and quadratically-weighted average electron densities in the region…

Solar and Stellar Astrophysics · Physics 2015-05-13 E. Buchlin , J. -C. Vial

We present an analysis of deep $\textit{JWST}$/NIRSpec spectra of star-forming galaxies at $z\simeq1.4-10$, observed as part of the AURORA survey. We infer median low-ionization electron densities of $268_{-49}^{+45}~\rm cm^{-3}$,…

The RS CVn type binary star GT Mus was observed during its quiescence using the Resolve X-ray microcalorimeter spectrometer onboard XRISM. The main and satellite lines of the Fe XXIV--XXVI K-shell transitions were resolved for the first…

We study temperature and density sensitivities of ratios of Si XI soft X-ray emission lines, in the wavelength range of 43--54\AA . The typical temperature of the formation of the analyzed lines is around 1.6~MK, which makes this analysis…

Astrophysics · Physics 2008-11-26 G. Y. Liang , G. Zhao
‹ Prev 1 2 3 10 Next ›