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Related papers: Coronal emission lines as thermometers

200 papers

Remote sensing experiments require high-accuracy, preferably sub-percent, line intensities and in response to this need we present computed room temperature line lists for six symmetric isotopologues of carbon dioxide: $^{13}$C$^{16}$O$_2$,…

Earth and Planetary Astrophysics · Physics 2017-11-01 Emil J. Zak , Jonathan Tennyson , Oleg L. Polyansky , Lorenzo Lodi , Nikolay F. Zobov , Sergei A. Tashkun , Valery I. Perevalov

Previous solar observations have shown that coronal loops near 1 MK are difficult to reconcile with simple heating models. These loops have lifetimes that are long relative to a radiative cooling time, suggesting quasi-steady heating. The…

We are interested in electrons kinetics in a stellar atmosphere to validate or invalidate the usually accepted hypothesis of thermalisation of electrons. For this purpose, we calculate the velocity distribution function of electrons by…

Astrophysics · Physics 2007-05-23 L. Chevallier

We review the accuracy of existing \ion{Fe}{17} X-ray line emission models by comparing them with an extensive analysis of \textit{Chandra} high energy transmission grating (HETG) observations of stellar coronae. We find significant…

Solar and Stellar Astrophysics · Physics 2009-05-06 M. F. Gu

We present spectroscopic observations of ionized gas in the disk-halo regions of five edge-on galaxies, covering a wavelength range from [OII] 3727A to [SII] 6716.4A. The inclusion of the [OII] emission provides additional constraints on…

Astrophysics · Physics 2009-11-07 B. Otte , J. S. Gallagher , R. J. Reynolds

The fundamental nature and extent of the coronal line region (CLR), which may serve as a vital tracer for Active Galactic Nucleus (AGN) activity, remain unresolved. Previous studies suggest that the CLR is produced by AGN-driven outflows…

Using photoemission intensities and a detection system employed by many groups in the electron spectroscopy community as an example, we have quantitatively characterized and corrected detector non-linearity effects over the full dynamic…

Instrumentation and Detectors · Physics 2007-05-23 N. Mannella , S. Marchesini , A. W. Kay , A. Nambu , T. Gresch , S. -H. Yang , B. S. Mun , J. M. Bussat , A. Rosenhahn , C. S. Fadley

The opening-up of the magnetic field during solar eruptive events is often accompanied by a dimming of the local coronal emission. From observations of filament eruptions recorded with the Extreme-Ultraviolet Imager on STEREO during…

Solar and Stellar Astrophysics · Physics 2011-03-10 Eva Robbrecht , Yi-Ming Wang

The Chandra X-ray Observatory grating spectrometers allow study of stellar spectra at resolutions on the order of 1000. Prior x-ray observatories' low resolution data have shown that nearly all classes of stars emit x-rays. Chandra reveals…

Astrophysics · Physics 2009-11-10 David P. Huenemoerder

These lectures are intended to present a simple but relatively complete description of the theory needed to understand the formation of lines in non-local thermodynamical equilibrium (NLTE), without appealing to any previous knowledge…

Astrophysics · Physics 2007-05-23 Suzy Collin

Spectroscopic diagnostics of solar coronal plasmas critically depends on the uncertainty in the measured line intensities. One of the main sources of uncertainty is instrumental scattered light, which is potentially most important in…

Solar and Stellar Astrophysics · Physics 2018-04-04 Carolyn Wendeln , Enrico Landi

Recent high-resolution imaging and spectroscopic observations have generated renewed interest in spicules' role in explaining the hot corona. Some studies suggest that some spicules, often classified as type II, may provide significant mass…

Solar and Stellar Astrophysics · Physics 2022-10-05 Shanwlee Sow Mondal , James A. Klimchuk , Aveek Sarkar

Determining temperatures in molecular clouds from ratios of CO rotational lines or from ratios of continuum emission in different wavelength bands suffers from reduced temperature sensitivity in the high-temperature limit. In theory, the…

Astrophysics · Physics 2008-11-26 W. F. Wall

All theories that attempt to explain the heating of the high temperature plasma observed in the solar corona are based on short bursts of energy. The intensities and velocities measured in the cores of quiescent active regions, however, can…

Solar and Stellar Astrophysics · Physics 2015-06-05 Fana M. Mulu-Moore , Amy R. Winebarger , Harry P. Warren

We report on the discovery of periodic coronal rain in an off-limb sequence of {\it Solar Dynamics Observatory}/Atmospheric Imaging Assembly images. The showers are co-spatial and in phase with periodic (6.6~hr) intensity pulsations of…

Solar and Stellar Astrophysics · Physics 2018-02-21 F. Auchère , C. froment , E. Soubrié , P. Antolin , R. Oliver , G. Pelouze

We have performed a systematic study of the Bremsstrahlung emission from the electrons in the plasma of a commercial 14.5 GHz Electron-Cyclotron Resonance Ion Source. The electronic spectral temperature and the product of ionic and…

The advent of 8--10 meter class telescopes enables direct measurement of the chemical properties in the ionized gas of cosmologically--distant galaxies with the same nebular analysis techniques used in local H II regions. We show that…

Astrophysics · Physics 2009-10-31 Henry A. Kobulnicky , Robert C. Kennicutt , James L. Pizagno

Aims: Our aim is to identify the dominant molecular cooling lines and characteristic emission features in the 1.3 mm window of distinct regions in the northern part of the Orion A molecular cloud. By defining and analysing template regions,…

Astrophysics of Galaxies · Physics 2020-04-15 N. Brinkmann , F. Wyrowski , J. Kauffmann , D. Colombo , K. M. Menten , X. D. Tang , R. Güsten

Thermoelectric power sensors can now be used as transfer standards, instead of bolometers, in the microcalorimeter technique. This alternative has the technical advantages to be less sensitive to absolute temperature and not downward…

Instrumentation and Detectors · Physics 2021-03-09 L. Brunetti , L. Oberto , E. Vremera

The EIC will deliver collisions of electrons with protons and nuclei at a wide variety of energies and at luminosities up to 1000 times higher than HERA. Precise measurement of both the scattered electron and the hadronic final state is…

Instrumentation and Detectors · Physics 2024-09-04 Henry T. Klest
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