Plasma diagnostics from broadening of spectral lines in nonuniform interatomic electric fields

1969 ◽  
Vol 11 (2) ◽  
pp. 870-874 ◽  
Author(s):  
L. I. Grechikhin
Keyword(s):  
Electric Fields ◽  
Plasma Diagnostics ◽  
Spectral Lines

Current Status of Solid-State X-Ray Systems

1985 ◽  
Vol 43 ◽  
pp. 158-161
Author(s):  
Martin Peckerar ◽  
Anastasios Tousimis
Keyword(s):  
Solid State ◽  
Electric Fields ◽  
Spectral Lines ◽  
Current Status ◽  
Mobile Charge ◽  
Electron Hole ◽  
X Ray ◽  
Sensing Systems ◽  
Transmission Electron ◽  
Electron Microscopes

Solid state x-ray sensing systems have been used for many years in conjunction with scanning and transmission electron microscopes. Such systems conveniently provide users with elemental area maps and quantitative chemical analyses of samples. Improvements on these tools are currently sought in the following areas: sensitivity at longer and shorter x-ray wavelengths and minimization of noise-broadening of spectral lines. In this paper, we review basic limitations and recent advances in each of these areas. Throughout the review, we emphasize the systems nature of the problem. That is. limitations exist not only in the sensor elements but also in the preamplifier/amplifier chain and in the interfaces between these components.Solid state x-ray sensors usually function by way of incident photons creating electron-hole pairs in semiconductor material. This radiation-produced mobile charge is swept into external circuitry by electric fields in the semiconductor bulk.

scholarly journals UV and x-ray spectral lines of Fe XXIII ion for plasma diagnostics

1996 ◽  
Vol 54 (5) ◽  
pp. 463-470 ◽  
Author(s):  
I Murakami ◽  
T Kato
Keyword(s):  
Plasma Diagnostics ◽  
Spectral Lines ◽  
X Ray

scholarly journals An investigation of the influence of electric fields on spectral lines: preliminary note

1906 ◽  
Vol 78 (521) ◽  
pp. 80-81
Keyword(s):  
Electric Fields ◽  
Electric Discharge ◽  
Wave Length ◽  
Spectral Lines ◽  
Mercury Vapour ◽  
Special Design ◽  
Preliminary Note ◽  
Electrical Fields ◽  
Interference Fringes ◽  
Discharge Tubes

In general the electrical fields used were those concomitant with the luminous electric discharge. An interferometer of the Michelson form and an echelon spectroscope of 18 plates were used to analyse the radiations. The results may be summarised as follows:— (1) End-on discharge tubes of special design, in which the light-source was a uniform column of luminous mercury vapour viewed in the direction of discharge, showed no change of wave-length as great as 1 part in 4,000,000 when the direction of the discharge was reversed. The pressure in the tube was varied from a few millimetres to a vacuum so high that there was but little luminosity. (2) The passage of Röntgen rays through the tube did not alter the wave-length nor the width of the mercury lines, to an extent sufficient to affect the visibility of interference fringes formed with a difference of path of 400,000 waves. When the luminous column was viewed at right angles to the direction of the discharge no polarisation effects in the radiation from it, due to the passage of the Röntgen rays, could be detected by a sensitive Savart plate and Nicol prism.

scholarly journals R-matrix electron-impact excitation data for the N-like iso-electronic sequence

2020 ◽  
Vol 643 ◽  
pp. A95
Author(s):  
Junjie Mao ◽  
N. R. Badnell ◽  
G. Del Zanna
Keyword(s):  
Electron Impact ◽  
Plasma Diagnostics ◽  
Spectral Lines ◽  
Impact Excitation ◽  
Electron Impact Excitation ◽  
Atomic Data ◽  
Astrophysical Plasma ◽  
Wide Range ◽  
The Impact ◽  
Effective Collision

Context. Spectral lines from N-like ions can be used to measure the temperature and density of various types of astrophysical plasmas. The atomic databases of astrophysical plasma modelling codes still have room for improvement in their electron-impact excitation data sets for N-like ions, especially for R-matrix data. This is particularly relevant for future observatories (e.g. Arcus), which will host high-resolution spectrometers. Aims. We aim to obtain level-resolved effective collision strengths for all transitions up to nl = 5d over a wide range of temperatures for N-like ions from O II to Zn XXIV (i.e. O+ to Zn23+) and to assess the accuracy of the present work. We also examine the impact of our new data on plasma diagnostics by modelling solar observations with CHIANTI. Methods. We carried out systematic R-matrix calculations for N-like ions, which included 725 fine-structure target levels in both the configuration interaction target and close-coupling collision expansions. The R-matrix intermediate coupling frame transformation method was used to calculate the collision strengths, while the AUTOSTRUCTURE code was used for the atomic structures. Results. We compare the present results for selected ions with those in archival databases and the literature. The comparison covers energy levels, oscillator strengths, and effective collision strengths. We show examples of improved plasma diagnostics when compared to CHIANTI models, which use only distorted wave data as well as some using previous R-matrix data. The electron-impact excitation data are archived according to the Atomic Data and Analysis Structure (ADAS) data class adf04 and will be available in OPEN-ADAS. The data can be used to improve the atomic databases for astrophysical plasma diagnostics.

On the Use of Spectral Lines Emitted by Carbon Ions for Plasma Diagnostics in Magnetic Fusion Devices

2008 ◽  
Author(s):  
M. Koubiti ◽  
T. Nakano ◽  
H. Capes ◽  
S. Ferri ◽  
L. Godbert-Mouret ◽  
...  
Keyword(s):  
Plasma Diagnostics ◽  
Spectral Lines ◽  
Magnetic Fusion ◽  
Carbon Ions

scholarly journals Исследование напряжeнности внутренних электрических полей в активной области светодиодных структур на основе InGaN/GaN с разным числом квантовых ям методом спектроскопии электропропускания

2020 ◽  
Vol 54 (4) ◽  
pp. 420
Author(s):  
А.Э. Асланян ◽  
Л.П. Авакянц ◽  
А.В. Червяков ◽  
А.Н. Туркин ◽  
С.С. Мирзаи ◽  
...  
Keyword(s):  
Active Region ◽  
Quantum Well ◽  
Quantum Wells ◽  
Electric Fields ◽  
Green Emission ◽  
Spectral Lines ◽  
Interband Transitions ◽  
Barrier Type ◽  
Piezoelectric Field

Abstract The internal electric fields of InGaN/GaN-based green-emission LED heterostructures with various numbers of quantum wells in the active region are investigated by electrotransmission spectroscopy. The frequencies of the observed spectral lines are attributed to possible types of interband transitions. An increase in the number of interband transitions of the “quantum well—quantum barrier” type with an increase in the number of quantum wells is found. This is explained by the nonidentical degree of segregation of In atoms in different GaN barriers layers. The strength of internal electric fields in quantum wells is calculated for various values of the bias of the p – n junction using a series of electrotransmission spectra. It is found that the strength of the internal piezoelectric field decreases from 3.20 to 2.82 MV/cm with an increase in the number of quantum wells.

Sign in / Sign up

Export Citation Format

Share Document