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Related papers: A New Approach to Calculate Coronal Electron Densi…

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The goal of this paper is to apply statistical methods to determine electrons densities and their errors from measurements of density-sensitive line intensities in the quiet Sun. Three methods are employed. The first is the use of…

Solar and Stellar Astrophysics · Physics 2020-06-17 Kenneth Dere

We present a model for the intensity of optically thin EUV emission for a plasma atmosphere. We apply our model to the solar corona as observed using the six optically thin EUV channels of the SDO/AIA instrument. The emissivity of the…

Solar and Stellar Astrophysics · Physics 2020-03-31 D. J. Pascoe , A. Smyrli , T. Van Doorsselaere

The calculation of the molecular column density from molecular spectral (rotational or ro-vibrational) transition measurements is one of the most basic quantities derived from molecular spectroscopy. Starting from first principles where we…

Instrumentation and Methods for Astrophysics · Physics 2017-04-10 Jeffrey G. Mangum , Yancy L. Shirley

Determination of the coronal electron density by the inversion of white-light polarized brightness (pB) measurements by coronagraphs is a classic problem in solar physics. An inversion technique based on the spherically symmetric geometry…

Solar and Stellar Astrophysics · Physics 2014-06-30 Tongjiang Wang , Joseph M. Davila

Comparison of appropriate theoretical derived line ratios with observational data can yield estimates of a plasma's physical parameters, such as electron density or temperature. The usual practice in the calculation of the line ratio is the…

Solar and Stellar Astrophysics · Physics 2014-11-20 J. G. Doyle , S. Chapman , P. Bryans , D. Perez-Suarez , A. Singh , H. Summers , D. W. Savin

Solar flare electron acceleration is an efficient process, but its properties (mechanism, location) are not well constrained. Via hard X-ray (HXR) emission, we routinely observe energetic electrons at the Sun, and sometimes we detect…

Solar and Stellar Astrophysics · Physics 2023-10-09 Ross Pallister , Natasha L. S. Jeffrey

We reach a thermodynamic interpretation of CODET model and its prediction to electrons density and temperature grounded on the physics of hydro magnetism in global equilibrium. The thermodynamic interpretation finds consistency with the…

Solar and Stellar Astrophysics · Physics 2020-05-19 Daniel B. Berdichevsky , Jenny M. Rodríguez Gómez , Luis E. Vieira , Allison Dal Lago

The grating instruments on board Chandra and XMM-Newton now allow measurements of electron densities. These rely on the ratios of fluxes in emission lines, where one line depends on both collisional and radiative decay rates. The electron…

Astrophysics · Physics 2009-11-10 Jan-Uwe Ness , Carole Jordan

We have reanalyzed SUMER observations of a parcel of coronal gas using new collisional ionization equilibrium (CIE) calculations. These improved CIE fractional abundances were calculated using state-of-the-art electron-ion recombination…

Astrophysics · Physics 2011-02-11 P. Bryans , E. Landi , D. W. Savin

Measurement of the coronal magnetic field is a crucial ingredient in understanding the nature of solar coronal phenomena at all scales. We employed STEREO/COR1 data obtained during a deep minimum of solar activity in February 2008…

Solar and Stellar Astrophysics · Physics 2014-05-06 M. Kramar , V. Airapetian , Z. Mikić , J. Davila

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

Measurement of the coronal magnetic field is a crucial ingredient in understanding the nature of solar coronal dynamic phenomena at all scales. We employ STEREO/COR1 data obtained near maximum of solar activity in December 2012 (Carrington…

Solar and Stellar Astrophysics · Physics 2016-04-05 Maxim Kramar , Vladimir Airapetian , Haosheng Lin

The plasma parameters such as the electron density and temperature plays a key role in the dynamics of the solar atmosphere. These characteristics are important in solar physics, because they can help to understand the physics in the solar…

Solar and Stellar Astrophysics · Physics 2018-04-12 J. M Rodríguez Gómez , L. Vieira , A. Dal Lago , J. Palacios

It is argued that depolarization of solar radio bursts requires reflection off boundary layers no thicker than about a wavelength (a few meters at most) between regions with large density ratios. The implied inhomogeneities suggest that the…

Astrophysics · Physics 2009-11-13 D. B Melrose

Coronal holes are large-scale structures in the solar atmosphere that feature a reduced temperature and density in comparison to the surrounding quiet Sun and are usually associated with open magnetic fields. We perform a differential…

Solar and Stellar Astrophysics · Physics 2021-03-01 Stephan G. Heinemann , Jonas Saqri , Astrid M. Veronig , Stefan J. Hofmeister , Manuela Temmer

A technique is described for measuring electrical currents in the solar corona. It uses radioastronomical polarization measurements of a spatially-extended radio source viewed through the corona. The observations yield the difference in the…

Astrophysics · Physics 2009-11-13 Steven R. Spangler

Heat transport in the solar corona and wind is still a major unsolved astrophysical problem. Because of the key role played by electrons, the electron density and temperature(s) are important prerequisites for understanding these plasmas.…

The critical need to study the magnetic field in the solar corona is highlighted by recent observational facilities, such as DKIST and Aditya-L1. A powerful tool for probing the magnetism of the solar corona is forward modeling of the…

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

Most of the baryons in the Universe are thought to be contained within filaments of galaxies, but as yet, no single study has published the observed properties of a large sample of known filaments to determine typical physical…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Amelia Fraser-McKelvie , Kevin A. Pimbblet , Jasmina S. Lazendic