Measurement of plasma parameters of a quasistationary plasma accelerator from self-absorbed spectral lines

1992 ◽  
Vol 56 (3) ◽  
pp. 281-286
Author(s):  
Ya. F. Volkov ◽  
V. V. Marinin ◽  
N. I. Mitina ◽  
M. A. Tiarov ◽  
S. A. Trubchaninov
Keyword(s):  
Plasma Accelerator ◽  
Spectral Lines ◽  
Plasma Parameters

scholarly journals Studies of plasma interactions with tungsten targets in PF-1000U facility

Nukleonika ◽  
2016 ◽  
Vol 61 (2) ◽  
pp. 149-153
Author(s):  
Maryna S. Ladygina ◽  
Elzbieta Skladnik-Sadowska ◽  
Dobromil R. Zaloga ◽  
Marek J. Sadowski ◽  
Monika Kubkowska ◽  
...  
Keyword(s):  
Experimental Studies ◽  
Optical Emission ◽  
Target Surface ◽  
Sample Surface ◽  
Optical Microscope ◽  
High Plasma ◽  
Spectral Lines ◽  
Optical Measurements ◽  
Plasma Stream ◽  
Plasma Parameters

Abstract This paper presents results of experimental studies of tungsten samples of 99.95% purity, which were irradiated by intense plasma-ion streams. The behaviour of tungsten, and particularly its structural change induced by high plasma loads, is of great importance for fusion technology. The reported measurements were performed within a modified PF-1000U plasma-focus facility operated at the IFPiLM in Warsaw, Poland. The working gas was pure deuterium. In order to determine the main plasma parameters and to study the behaviour of impurities at different instants of the plasma discharge, the optical emission spectroscopy was used. The dependence of plasma parameters on the initial charging voltage (16, 19 and 21 kV) was studied. Detailed optical measurements were performed during interactions of a plasma stream with the tungsten samples placed at the z-axis of the facility, at a distance of 6 cm from the electrode outlets. The recorded spectra showed distinct WI and WII spectral lines. Investigation of a target surface morphology, after its irradiation by intense plasma streams, was performed by means of an optical microscope. The observations revealed that some amounts of the electrodes material (mainly copper) were deposited upon the irradiated sample surface. In all the cases, melted zones were observed upon the irradiated target surface, and in experiments performed at the highest charging voltage there were formed some cracks.

scholarly journals The temperature characteristics of plasma induced by femtosecond laser radiation

2019 ◽  
Vol 220 ◽  
pp. 03034
Author(s):  
Sergei Arakelyan ◽  
Svetlana Zhirnova ◽  
Arkady Galkin ◽  
Dmitriy Kochuev ◽  
Elena Shamanskaya ◽  
...  
Keyword(s):  
Laser Radiation ◽  
Femtosecond Laser ◽  
Electron Concentration ◽  
Relative Intensity ◽  
Collision Frequency ◽  
Plasma Temperature ◽  
Spectral Lines ◽  
Femtosecond Laser Radiation ◽  
Plasma Parameters ◽  
Atoms And Molecules

In this work, the plasma temperature in an argon and nitrogen medium is measured at various pressure values. Such data can be used to calculate plasma parameters: electron concentration, collision frequency with atoms and molecules, etc. Two approaches are used to measure temperature: using a pyrometer and measuring the relative intensity of spectral lines.

scholarly journals Investigations concerning plasma parameters and population inversion in laser-produced counterstreaming plasmas

1991 ◽  
Vol 9 (2) ◽  
pp. 501-515 ◽  
Author(s):  
P. Glas ◽  
M. Schnürer
Keyword(s):  
Computational Analysis ◽  
Nuclear Charge ◽  
Gain Coefficient ◽  
Spectral Lines ◽  
Interaction Zone ◽  
Electron Number ◽  
Plasma Parameters ◽  
X Ray ◽  
Spatial Intensity Distribution ◽  
Resonance Transitions

We investigated the case where two laser-produced plasmas collide nearly head on. Special attention was devoted to the fundamentals necessary to realize a coherent X-ray source. A gas-dynamic computational analysis was performed to understand the evolution of the density, the temperature, and the velocity of merging plasmas. The spatial intensity distribution of selected spectral lines reveals that the interaction of plasmas of different nuclear charge and charge state is not strictly collision dominated. Using spectral line intensity ratios, we determined electron temperatures and electron number densities, as well as the intensity inversion on the 4–1 to 3–1 resonance transitions of [He]-like Al. Inversion occurs in the vicinity of the targets if identical materials are used (Al–Al) and is possibly indicated in the interaction zone for different ones (Al–Cu), too. The inversion factors (and the gain coefficient) for the 4–3 transition of [He]-like Al at about 130 Å were estimated.

scholarly journals High-precision measurement of velocity profiles in laser-created chlorine plasma

1995 ◽  
Vol 13 (4) ◽  
pp. 503-510 ◽  
Author(s):  
O. Renner ◽  
E. Krouský ◽  
T. Mißalla ◽  
E. Förster ◽  
G. Hölzer
Keyword(s):  
Spectral Lines ◽  
Plasma Parameters ◽  
High Precision Measurement ◽  
One Dimensional ◽  
Electron Temperature Gradient ◽  
Spatially Resolved ◽  
Doppler Shifts ◽  
Velocity Gradients ◽  
Marquardt Algorithm ◽  
The One

A vertical dispersion variant of the Johann spectrometer has been used to record the highresolution X-ray spectra of the chlorine He-like resonance line group emitted from lowradiance plasma. The emission profiles were measured at two observation angles and decomposed into single spectral lines by using a fit based on the Levenberg-Marquardt algorithm. The results of computerized analysis of the one-dimensional (1-D) spatially resolved spectra were used to evaluate the distribution of the main plasma parameters. The electron temperature gradient 7.5·104 eV cm-1 was computed by modeling the measured spectra with the collisional-radiative package RATION. The blowoff maximum velocities 4.2–6.1·107 cm s-1 and the velocity gradients 0.9–1.6·109 s-1 were determined from the Doppler shifts of individual spectral lines within their different spatial extent.

Study of plasma parameters in a pulsed plasma accelerator using triple Langmuir probe

2018 ◽  
Vol 25 (1) ◽  
pp. 013532 ◽  
Author(s):  
S. Borthakur ◽  
N. Talukdar ◽  
N. K. Neog ◽  
T. K. Borthakur
Keyword(s):  
Langmuir Probe ◽  
Plasma Accelerator ◽  
Pulsed Plasma ◽  
Plasma Parameters

scholarly journals On the stark broadening of Os II spectral lines

2020 ◽  
Vol 10 (2) ◽  
pp. 65-70
Author(s):  
Milan Dimitrijević
Keyword(s):  
Electron Density ◽  
Spectral Lines ◽  
Half Maximum ◽  
Stark Broadening ◽  
Plasma Parameters ◽  
And Shifts

Stark broadening parameters, full widths at half maximum (FWHM) and shifts for 13 Os II lines have been calculated. The plasma parameters are: electron density of 1017 cm-3 and temperatures from 5 000 K to 80 000 K. Calculations have been performed with the simplified modified semiempirical (SMSE) approach. The results are also used for the consideration of Strak width and shift regularities within the Os II 6s6D-6p6Do multiplet.

Spectral Analysis of a Quiescent Filament

1994 ◽  
Vol 144 ◽  
pp. 361-363
Author(s):  
P. Kotrč ◽  
P. Heinzel ◽  
A. V. Gorshkov ◽  
E. V. Kononovich ◽  
Yu. A. Kupryakov ◽  
...  
Keyword(s):  
Spectral Analysis ◽  
Cloud Model ◽  
Spectral Lines ◽  
Plasma Parameters ◽  
Preliminary Results ◽  
Quiescent Filament

AbstractWe have determined principal plasma parameters in a filament by applying the appropriate cloud model to several observed spectral lines. Then we compared them to prominence models from the recent numerical NLTE modelling of Gouttebrozeet al. (1993) (referred to as GHV). Some preliminary results of such an attempt are described and related problems are briefly discussed.

scholarly journals ON THE STARK BROADENING OF Os II SPECTRAL LINES

2020 ◽  
Vol 10 (2) ◽  
Author(s):  
Milan S. Dimitrijević
Keyword(s):  
Electron Density ◽  
Spectral Lines ◽  
Half Maximum ◽  
Stark Broadening ◽  
Plasma Parameters ◽  
And Shifts

Stark broadening parameters, full widths at half maximum (FWHM) and shifts for 13 Os II lines have been calculated. The plasma parameters are: electron density of 1017 cm-3 and temperatures from 5 000 K to 80 000 K. Calculations have been performed with the simplified modified semiempirical (SMSE) approach. The results are also used for the consideration of Strak width and shift regularities within the Os II 6s6D-6p6Do multiplet.

scholarly journals Formation and dynamics of transequatorial loops

2020 ◽  
Vol 640 ◽  
pp. A3
Author(s):  
Avyarthana Ghosh ◽  
Durgesh Tripathi
Keyword(s):  
Magnetic Reconnection ◽  
Extreme Ultraviolet ◽  
Imaging Techniques ◽  
Dynamical Evolution ◽  
Disk Center ◽  
Spectral Lines ◽  
Solar Dynamics Observatory ◽  
Plasma Parameters ◽  
Imaging Spectrometer ◽  
Solar Dynamics

Aims. We aim to study the dynamical evolution of transequatorial loops (TELs) using imaging techniques and spectroscopy. Methods. We used the images recorded by the Atmospheric Imaging Assembly and the Helioseismic Magnetic Imager on board the Solar Dynamics Observatory together with spectroscopic observations taken from the Extreme-Ultraviolet Imaging Spectrometer on board Hinode. Results. The data from the AIA 193 Å channel show that TELs are formed between AR 12230 and a newly emerging AR 12234, evolving between 10 and 14 December 2014. The xt-plots for 12 December 2014, obtained using AIA 193 Å data, reveal signatures of inflow and outflow towards an X-region. High-cadence AIA images also show recurrent intensity enhancements in close proximity to the X-region (P2), which is observed to have higher intensities for spectral lines that are formed at log T[K] = 6.20 and voids at other higher temperatures. The electron densities and temperatures in the X-region (and P2) are maintained steadily at log Ne= 8.5–8.7 cm−3 and log T[K] = 6.20, respectively. Doppler velocities in the X-region show predominant redshifts by about 5–8 km s−1 when they are closer to the disk center but blueshifts (along with some zero-velocity pixels) when away from the center. The full-width-half-maximum maps reveal non-thermal velocities of about 27–30 km s−1 for Fe XII, Fe XIII, and Fe XV lines. However, the brightest pixels have nonthermal velocities ∼62 km s−1 for Fe XII and Fe XIII lines. On the contrary, the dark X-region for Fe XV line have the highest non-thermal velocity (∼115 km s−1). Conclusions. We conclude that the TELs are formed due to magnetic reconnection. We further note that the TELs themselves undergo magnetic reconnection, which leads to the re-formation of loops among individual ARs. Moreover, this study, for the first time, provides measurements of plasma parameters in X-regions, thereby providing essential constraints for theoretical studies.

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