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Related papers: Solar UV and X-Ray Spectral Diagnostics

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Solar flare hard X-ray spectroscopy serves as a key diagnostic of the accelerated electron spectrum. However, the standard approach using the collisional cold thick-target model poorly constrains the lower-energy part of the accelerated…

Solar and Stellar Astrophysics · Physics 2019-02-05 Eduard P. Kontar , Natasha L. S. Jeffrey , A. Gordon Emslie

This paper considers the problem of modeling the light polarization that emerges from an astrophysical plasma composed of atoms whose excitation state is significantly influenced by the anisotropy of the incident radiation field. In…

Solar and Stellar Astrophysics · Physics 2011-05-03 Javier Trujillo Bueno

The detailed knowledge of plasma heating and acceleration region properties presents a major observational challenge in solar flare physics. Using the Ramaty High Energy Solar Spectroscopic Imager (RHESSI), the high temperature differential…

Solar and Stellar Astrophysics · Physics 2015-12-02 Natasha Jeffrey , Eduard Kontar , Brian Dennis

Differential Emission Measure (DEM) inversion methods use the brightness of a set of emission lines to infer the line-of-sight (LOS) distribution of the electron temperature ($T_e$) in the corona. DEM inversions have been traditionally…

Solar and Stellar Astrophysics · Physics 2023-07-12 Benjamin Boe , Cooper Downs , Shadia Habbal

Studying the atmospheres of exoplanets is one of the most promising ways to learn about distant worlds beyond our solar system. The composition of an exoplanet's atmosphere can provide critical insights into its geology and potential…

Earth and Planetary Astrophysics · Physics 2025-05-05 Surangkhana Rukdee

Ultrarelativistic collisions of large nuclei produce a short-lived plasma of deconfined quarks and gluons. Of all the GeV-energy photons detected in these nuclear collisions, only a small number are emitted directly by the quark-gluon…

Nuclear Theory · Physics 2022-05-26 Jean-François Paquet , Steffen A. Bass

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

We used data from the Helioseismic and Magnetic Imager (HMI), and Atmospheric Imaging Assembly (AIA) on the \textit{Solar Dynamics Observatory} (SDO) to study coronal loops at small scales, emerging in the quiet Sun. With HMI line-of-sight…

Solar and Stellar Astrophysics · Physics 2013-04-15 LP. Chitta , R. Kariyappa , A. A. van Ballegooijen , E. E. DeLuca , S. S. Hasan , A. Hanslmeier

We measured for the first time the electron density in an Extreme Ultra-Violet induced plasma. This is achieved in a low-pressure argon plasma by using a method called microwave cavity resonance spectroscopy. The measured electron density…

Plasma Physics · Physics 2014-07-07 R. M. van der Horst , J. Beckers , S. Nijdam , G. M. W. Kroesen

The dynamics of photo-excited charge carriers, particularly their transport and interactions with defects and interfaces, play an essential role in determining the performance of a wide range of solar and optoelectronic devices. A thorough…

Materials Science · Physics 2017-08-07 Bolin Liao , Ebrahim Najafi

Spectroscopy in the infrared provides a means to assess important properties of the plasma in gaseous nebulae. We present some of our own work that illustrates the need for interactions between the themes of this conference - astronomical…

Accurate estimation of thermospheric density is critical for precise modeling of satellite drag forces in low Earth orbit (LEO). Improving this estimation is crucial to tasks such as state estimation, collision avoidance, and re-entry…

Understanding the density structure of the solar corona is important for modeling both coronal heating and the solar wind. Direct measurements are difficult because of line-of-sight integration and possible unresolved structures. We present…

Solar and Stellar Astrophysics · Physics 2016-09-28 Michael Hahn , Daniel Wolf Savin

Time- and Angle-resolved photoelectron spectroscopy from surfaces can be used to record the dynamics of electrons and holes in condensed matter on ultrafast time scales. However, ultrafast photoemission experiments using extreme-ultraviolet…

The World Space Observatory for Ultraviolet (WSO-UV) is an orbital optical telescope with a 1.7 m-diameter primary mirror currently under development. The WSO-UV is aimed to operate in the 115-310 nm UV spectral range. Its two major science…

The ubiquitous diffuse soft (1/4 keV) X-ray background was one of the earliest discoveries of X-ray astronomy. At least some of the emission may arise from charge exchange between solar wind ions and neutral atoms in the heliosphere, but no…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Randall K. Smith , Adam R. Foster , Richard J. Edgar , Nancy S. Brickhouse

In our solar system, the densely cloud-covered atmosphere of Venus stands out as an example of how polarimetry can be used to gain information on cloud composition and particle mean radius. With current interest running high on discovering…

Earth and Planetary Astrophysics · Physics 2022-12-14 Robert A. West , Philip Dumont , Renyu Hu , Vijay Natraj , James Breckinridge , Pin Chen

We investigate and evaluate the contribution of the ultraviolet radiation spectrum on the temperature and efficiency of commercial crystalline silicon-based photovoltaics (PVs) that operate outdoors. The investigation is performed by…

Solar flare electron acceleration is an extremely efficient process, but the method of acceleration is not well constrained. Two of the essential diagnostics: electron anisotropy (velocity angle to the guiding magnetic field) and the high…

Solar and Stellar Astrophysics · Physics 2020-12-21 Natasha L. S. Jeffrey , Pascal Saint-Hilaire , Eduard P. Kontar

Cosmic photons can be efficiently collected by broadband intensity mapping but information on their emission redshift and frequency is largely lost. We introduce a technique to statistically recover these otherwise collapsed dimensions by…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-12 Yi-Kuan Chiang , Brice Ménard , David Schiminovich