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Related papers: Ion-by-Ion DEM Determination: I. Method

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In a previous paper we have described 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…

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

We discuss here various methodologies and an optimal strategy of the temperature and emission measure diagnostics based on Hinode X-Ray Telescope data. As an example of our results we present determination of the temperature distribution of…

Astrophysics · Physics 2015-05-13 M. Siarkowski , R. Falewicz , A. Kepa , P. Rudawy

In collisional ionization equilibrium (CIE), the X-ray spectrum from a plasma depends on the distribution of emission measure over temperature (DEM). Due to the well-known ill conditioning problem, no precisely resolved DEM can be inverted…

High Energy Astrophysical Phenomena · Physics 2014-01-28 K. G. Gayley

The Differential Emission Measure (DEM) analysis is one of the most used diagnostic tools for solar and stellar coronae. Being an inverse problem, it has limitations due to the presence of random and systematic errors. We present in theses…

Solar and Stellar Astrophysics · Physics 2013-06-17 Chloé Guennou , Frédéric Auchère , Elie Soubrié , Karine Bocchialini , Susanna Parenti

Inverse problems are of great importance in astrophysics for deriving information about the physical characteristics of hot optically thin plasma sources from their EUV and X-ray spectra. We describe and test an iterative method developed…

Solar and Stellar Astrophysics · Physics 2014-01-24 F. F. Goryaev , S. Parenti , A. M. Urnov , S. N. Oparin , J. -F. Hochedez , F. Reale

Thermal plasma of solar atmosphere includes a wide range of temperatures. This plasma is often quantified, both in observations and models, by a differential emission measure (DEM). DEM is a distribution of the thermal electron density…

Solar and Stellar Astrophysics · Physics 2021-06-23 Gregory D. Fleishman , Alexey A. Kuznetsov , Enrico Landi

DEM analysis is a major diagnostic tool for stellar atmospheres. But both its derivation and its interpretation are notably difficult because of random and systematic errors, and the inverse nature of the problem. We use simulations with…

Solar and Stellar Astrophysics · Physics 2013-06-17 Chloé Guennou , Frédéric Auchère , Elie Soubrié , Karine Bocchialini , Susanna Parenti

X-Ray and Ultraviolet (UV) observations of the outer solar atmosphere have been used for many decades to measure the fundamental parameters of the solar plasma. This review focuses on the optically thin emission from the solar atmosphere,…

Solar and Stellar Astrophysics · Physics 2018-09-06 Giulio Del Zanna , Helen E. Mason

Electrons densities in different locations of our galaxy are obtained in pulsar astronomy by dividing the dispersion measure (DM) by the distance of the pulsar to Earth. The properties of the interstellar plasma are related to its heating.…

High Energy Astrophysical Phenomena · Physics 2023-12-05 Y. Ben-Aryeh

The reconstruction of the differential emission measure (DEM) from observations of spectral line intensities provides information on the temperature distribution of the emission measure in the region observed. The inversion process is known…

Solar and Stellar Astrophysics · Physics 2022-05-18 Kenneth P. Dere

In this paper, the ability of the Hinode/EIS instrument to detect radiative signatures of coronal heating is investigated. Recent observational studies of AR cores suggest that both the low and high frequency heating mechanisms are…

Solar and Stellar Astrophysics · Physics 2015-06-16 Chloé Guennou , Frédéric Auchère , James A. Klimchuk , Karine Bocchialini , Susanna Parenti

X-ray emission spectroscopy is a well-established technique used to study continuum lowering in dense plasmas. It relies on accurate atomic physics models to robustly reproduce high-resolution emission spectra, and depends on our ability to…

Plasma Physics · Physics 2020-01-22 M. F. Kasim , J. S. Wark , S. M. Vinko

Using methods of differential evolution (DE,) we determined the coronal elemental abundances and the differential emission measure (DEM) distributions for the plasma flaring on 2003 January 21. The analyses have been based on RESIK X-ray…

Solar and Stellar Astrophysics · Physics 2022-03-09 Anna Kepa , Barbara Sylwester , Marek Siarkowski , Janusz Sylwester

We developed a method to compute the temperature and density structure along the line of sight by inversion of the differential emission measure (DEM), under the assumptions of stratification and hydrostatic equilibrium. We applied this…

Solar and Stellar Astrophysics · Physics 2019-02-27 C. E. Alissandrakis , V. M. Bogod , T. I. Kaltman , S. Patsourakos , N. G. Peterova

This paper introduces a novel approach for automated estimation of plasma temperature and density using emission spectroscopy, integrating Bayesian inference with sophisticated physical models. We provide an in-depth examination of Bayesian…

Plasma Physics · Physics 2023-12-21 Todd A. Oliver , Craig Michoski , Samuel Langendorf , Andrew LaJoie

We investigate the evolution of differential emission measure distribution (DEM[T]) in various phases of a B8.3 flare, which occurred on July 04, 2009. We analyze the soft X-ray (SXR) emission in 1.6-8.0 keV range, recorded collectively by…

Solar and Stellar Astrophysics · Physics 2016-06-08 Arun Kumar Awasthi , Barbara Sylwester , Janusz Sylwester , Rajmal Jain

The nuclear reactions in a plasma system with energy distribution deviated from Maxwellian are proved to have some unique characteristics including those in their product energy spectrum. Based on this, a new nuclear diagnostic scheme for…

Plasma Physics · Physics 2022-11-21 K. Li , Z. Y. Liu , A. D. Liu , B. Qiao

Collisional plasma shocks generated from supersonic flows are an important feature in many astrophysical and laboratory high-energy-density plasmas. Compared to single-ion-species plasma shocks, plasma shock fronts with multiple ion species…

Plasma Physics · Physics 2023-04-05 F. Chu , A. L. LaJoie , B. D. Keenan , L. Webster , S. J. Langendorf , M. A. Gilmore

High-energy emission spectra from the outer atmospheres of late-type stars represent an important feature of the stellar activity in several contexts, such as the photoevaporation and photochemistry of planetary atmospheres or the modeling…

Solar and Stellar Astrophysics · Physics 2025-11-17 Antonio Maggio , Ignazio Pillitteri , Jorge Sanz-Forcada , Giuseppina Micela

Aims: We systematically explore a plausible subset of the parameter space involving effective temperatures and metallicities of the ionizing stellar sources, the effects of the hardening of their radiation by surrounding leaky HII regions…

Astrophysics of Galaxies · Physics 2019-02-13 J. A. Weber , A. W. A. Pauldrach , T. L. Hoffmann
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