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Related papers: Constraining coronal heating: employing Bayesian a…

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Any successful model of coronal loops must explain a number of observed properties. For warm (~ 1 MK) loops, these include: 1. excess density, 2. flat temperature profile, 3. super-hydrostatic scale height, 4. unstructured intensity…

Solar and Stellar Astrophysics · Physics 2014-11-20 J. A. Klimchuk , J. T. Karpen , S. K. Antiochos

{Observations of the solar atmosphere have shown that magnetohydrodynamic waves are ubiquitous throughout. Improvements in instrumentation and the techniques used for measurement of the waves now enables subtleties of competing theoretical…

Solar and Stellar Astrophysics · Physics 2016-09-28 R. J. Morton , K. Mooroogen

The Sun's corona has interested researchers for multiple reasons, including the search for solution for the famous coronal heating problem and a purely practical consideration of predicting geomagnetic storms on Earth. There exist numerous…

Solar and Stellar Astrophysics · Physics 2019-11-13 Dan Aksim , Alexey Melnikov , Dmitry Pavlov , Sergey Kurdubov

A specific implementation of Bayesian model averaging has recently been suggested as a method for the calibration of ensemble temperature forecasts. We point out the similarities between this new approach and an earlier method known as…

Atmospheric and Oceanic Physics · Physics 2007-05-23 Stephen Jewson

The solar corona is much hotter than the photosphere and chromosphere, but the physical mechanism responsible for heating the coronal plasma remains unidentified yet. The thermal microwave emission, which is produced in strong magnetic…

Solar and Stellar Astrophysics · Physics 2025-08-27 Alexey A. Kuznetsov , Gregory D. Fleishman , Gelu M. Nita , Sergey A. Anfinogentov

Recent observations of Krucker & Benz (1998) give strong support to Parker's hypothesis (Parker 1988) that small scale dissipative events make the main contribution to quiet Sun coronal heating. They also showed that these small scale…

Astrophysics · Physics 2009-11-06 V. Krasnoselskikh , O. Podladchikova , B. Lefebvre , N. Vilmer

In the present work we use a deep-exposure spectrum taken by the SUMER spectrometer in a polar coronal hole in 1996 to measure the ion temperatures of a large number of ions at many different heights above the limb between 0.03 and 0.17…

Astrophysics · Physics 2011-02-11 Enrico Landi , Steven R. Cranmer

We consider the problem of estimating a temperature-dependent thermal conductivity model (curve) from temperature measurements. We apply a Bayesian estimation approach that takes into account measurement errors and limited prior information…

Computational Engineering, Finance, and Science · Computer Science 2024-03-21 Rodrigo L. S. Silva , Clemens Verhoosel , Erik Quaeghebeur

Observations of the coronae of the Sun and of solar-like stars provide complementary information to advance our understanding of stellar magnetic activity, and of the processes leading to the heating of their outer atmospheres. While solar…

Solar and Stellar Astrophysics · Physics 2023-07-19 Paola Testa , Steve Saar , Jeremy Drake

Consistent experiment data are crucial to adjust parameters of physics models and to determine best estimates of observables. However, often experiment data are not consistent due to unrecognized systematic errors. Standard methods of…

Nuclear Theory · Physics 2018-03-05 Georg Schnabel

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

The solar atmosphere shows anomalous variation in temperature, starting from the 5500 K photosphere to the million-degree Kelvin corona. The corona itself expands into the interstellar medium as the free streaming solar wind, which…

Solar and Stellar Astrophysics · Physics 2023-04-05 Vishal Upendran

The hot solar corona exists because of the balance between radiative and conductive cooling and some counteracting heating mechanism which remains one of the major puzzles in solar physics. The coronal thermal equilibrium is perturbed by…

Solar and Stellar Astrophysics · Physics 2020-11-25 D. Y. Kolotkov , T. J. Duckenfield , V. M. Nakariakov

Coronal loops, constituting the basic building blocks of the active Sun, serve as primary targets to help understand the mechanisms responsible for maintaining multi-million Kelvin temperatures in the solar and stellar coronae. Despite…

Solar and Stellar Astrophysics · Physics 2017-01-11 S. Krishna Prasad , D. B. Jess , J. A. Klimchuk , D. Banerjee

The coronagraph is an instrument enables the investigation of faint features in the vicinity of the Sun, particularly coronal mass ejections (CMEs). So far coronagraphic observations have been mainly used to determine the geometric and…

Solar and Stellar Astrophysics · Physics 2017-01-18 Kyuhyoun Cho , Jongchul Chae , Eun-kyung Lim , Kyung-suk Cho , Su-Chan Bong , Heesu Yang

We demonstrate that two approximations to the chi^2 statistic as popularly employed by observational astronomers for fitting Poisson-distributed data can give rise to intrinsically biased model parameter estimates, even in the high counts…

Astrophysics · Physics 2009-11-13 Philip J. Humphrey , Wenhao Liu , David A. Buote

Statistical uncertainties in determining the temperatures of hot (0.5 keV to 10 keV) coronal plasmas are investigated. The statistical precision of various spectral temperature diagnostics is established by analyzing synthetic ASCA…

Astrophysics · Physics 2009-10-22 Douglas A. Swartz , S. L. O'Dell , M. E. Sulkanen , A. F. Tennant

We estimate the coronal density of Capella using the O VII and Fe XVII line systems in the soft X-ray regime that have been observed over the course of the Chandra mission. Our analysis combines measures of error due to uncertainty in the…

Solar and Stellar Astrophysics · Physics 2024-06-21 Xixi Yu , Vinay L. Kashyap , Giulio Del Zanna , David A. van Dyk , David C. Stenning , Connor P. Ballance , Harry P. Warren

Coronal loops are the basic structures of the solar transition region and corona. The understanding of physical mechanism behind the loop heating, plasma flows, and filling are still considered a major challenge in the solar physics. The…

Solar and Stellar Astrophysics · Physics 2015-02-24 G. R. Gupta , Durgesh Tripathi , Helen E. Mason

By introducing Crossing functions and hyper-parameters I show that the Bayesian interpretation of the Crossing Statistics [1] can be used trivially for the purpose of model selection among cosmological models. In this approach to falsify a…

Cosmology and Nongalactic Astrophysics · Physics 2012-05-24 Arman Shafieloo