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Related papers: Coronal emission lines as thermometers

200 papers

The nature of the interaction between low-excitation gas filaments at ~10^4 K, seen in optical line emission, and diffuse X-ray emitting coronal gas at ~10^7 K in the centers of galaxy clusters remains a puzzle. The presence of a strong,…

Visible-light observations of Coronal Mass Ejections (CMEs) performed with coronagraphs and heliospheric imagers (in primis on board the SOHO and STEREO missions) have offered so far the best way to study the kinematics and geometrical…

Solar and Stellar Astrophysics · Physics 2016-10-19 R. Susino , A. Bemporad

The accurate determination of electronic temperatures in metallic nanostructures is essential for many technological applications, like plasmon-enhanced catalysis or lithographic nanofabrication procedures. In this Letter we demonstrate…

Measurements of the temperature and density structure of the solar corona provide critical constraints on theories of coronal heating. Unfortunately, the complexity of the solar atmosphere, observational uncertainties, and the limitations…

Solar and Stellar Astrophysics · Physics 2009-07-22 Harry P. Warren , David H. Brooks

Coronal loops are plasma structures in the solar atmosphere with temperatures reaching millions of Kelvin, shaped and sustained by the magnetic field. However, their morphology and fundamental nature remain subjects of debate. By studying…

Solar and Stellar Astrophysics · Physics 2026-01-14 N. Vasantharaju , H. Peter , L. P. Chitta , S. Mandal

We present He-like line ratios (resonance, intercombination and forbidden lines) for totally and partially photoionized media. For solar plasmas, these line ratios are already widely used for density and temperature diagnostics of coronal…

Astrophysics · Physics 2009-10-31 Delphine Porquet , Jacques Dubau

Energy distribution of electrons in the plasma sustained by the electron-cyclotron resonance (ECR) discharge has a complicated shape as a function of various parameters that still remains unknown. Meanwhile, it is an important plasma…

Plasma Physics · Physics 2022-05-18 Elena Kiseleva , Ivan Izotov , Vadim Skalyga

We describe a technique to derive constraints on the differential emission measure (DEM) distribution, a measure of the temperature distribution, of collisionally ionized hot plasmas from their X-ray emission line spectra. This technique…

Astrophysics · Physics 2009-11-10 Patrick S. Wojdowski , Norbert S. Schulz

Turbulent mixing layers (TMLs) are ubiquitous in multiphase gas. They can potentially explain observations of high ions such as O VI, which have significant observed column densities despite short cooling times. Previously, we showed that…

Astrophysics of Galaxies · Physics 2021-09-01 Brent Tan , S. Peng Oh

In this paper we develop tools for observers to use when analysing nebular spectra for temperatures and metallicities, with two goals: to present a new, simple method to calculate equilibrium electron temperatures for collisionally excited…

Astrophysics of Galaxies · Physics 2013-07-18 David C. Nicholls , Michael A. Dopita , Ralph S. Sutherland , Lisa J. Kewley , Ethan Palay

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 analyze coordinated Hinode XRT and EIS observations of a non-flaring active region to investigate the thermal properties of coronal plasma taking advantage of the complementary diagnostics provided by the two instruments. In particular…

Solar and Stellar Astrophysics · Physics 2015-05-20 Paola Testa , Fabio Reale , Enrico Landi , Ed DeLuca , Vinay Kashyap

Theoretical calculations of the cooling potential of radiative cooling materials are crucial for determining their cooling capability under different meteorological conditions and evaluating their performance. To enable these calculations,…

Atmospheric and Oceanic Physics · Physics 2021-08-19 Jyotirmoy Mandal , Xin Huang , Aaswath P. Raman

Conical wire arrays with different opening angles are used as load of a 400kA, 1kA/ns generator. The differences in opening angle allow the study of the influence of the array geometry on the jet properties. The characterization of the jets…

We consider how to analyze microcalorimeter pulses for quantities that are nonlinear in the data, while preserving the signal-to-noise advantages of lin- ear optimal filtering. We successfully apply our chosen approach to compute the…

Instrumentation and Detectors · Physics 2018-04-18 J. W. Fowler , C. G. Pappas , B. K. Alpert , W. B. Doriese , G. C. O'Neil , J. N. Ullom , D. S. Swetz

The progress of semiconductor electronics toward ever-smaller length scales and associated higher power densities brings a need for new high-resolution thermal microscopy techniques. Traditional thermal microscopy is performed by detecting…

Materials Science · Physics 2015-05-13 Todd Brintlinger , Yi Qi , Kamal H. Baloch , David Goldhaber-Gordon , John Cumings

Using Hinode EUV Imaging Spectrometer (EIS) spectra recorded daily at Sun center from the end of 2006 to early 2011, we studied the long-term evolution of the quiet corona. The light curves of the higher temperature emission lines exhibit…

Solar and Stellar Astrophysics · Physics 2012-07-17 S. Kamio , J. T. Mariska

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

In this paper, we study the temperature and density properties of multiple structural components of coronal mass ejections (CMEs) using differential emission measure (DEM) analysis. The DEM analysis is based on the six-passband EUV…

Solar and Stellar Astrophysics · Physics 2015-06-11 X. Cheng , J. Zhang , S. H. Saar , M. D. Ding

It is shown that the anomalous resistivity, thermal conductivity, and magnetic pressure of hot plasmas can be explained by the assumption that the collisional electron-ion cross-section becomes constant above some critical temperature. This…

Plasma Physics · Physics 2007-05-23 Fedor V. Prigara