scholarly journals Stark broadening of resonant Cr II 3d5–3d44p spectral lines in hot stellar atmospheres

2013 ◽  
Vol 432 (3) ◽  
pp. 2247-2251 ◽  
Author(s):  
Z. Simić ◽  
M. S. Dimitrijević ◽  
S. Sahal-Bréchot
Keyword(s):  
Stellar Atmospheres ◽  
Spectral Lines ◽  
Stark Broadening

scholarly journals The effect of hyperfine splitting on Stark broadening for three blue-green Cu i lines in laser-induced plasma

2019 ◽  
Vol 488 (4) ◽  
pp. 5594-5603 ◽  
Author(s):  
A M Popov ◽  
N I Sushkov ◽  
S M Zaytsev ◽  
T A Labutin
Keyword(s):  
Hyperfine Splitting ◽  
Stark Effect ◽  
Stellar Atmospheres ◽  
Spectral Lines ◽  
Stark Broadening ◽  
Laser Induced Plasma ◽  
Radiation Sources ◽  
And Shifts ◽  
First Time ◽  
Existing Data

ABSTRACT Stark effect is observed in many natural and artificial plasmas and is of great importance for diagnostic purposes. Since this effect alters profiles of spectral lines, it should be taken into account when assessing chemical composition of radiation sources, including stars. Copper is one of the elements which studies of stellar atmospheres deal with. To this end, UV and visible Cu lines are used. However, there is a lack of agreement between existing data on their Stark parameters. It is therefore of interest to obtain new experimental data on these lines and to compare them to previous results. In this work, we have estimated Stark widths and shifts for three blue-green lines at 5105.54, 5153.24, and 5218.20 Å (corresponding transitions are [3d104p] 2P° → [3d94s2] 2D and [3d104d] 2D → [3d104p] 2P°) observed in a ‘long-spark’ laser-induced plasma. For the first time, we have accurately estimated an impact of hyperfine splitting on the profile shapes of the studied lines taking also into account the isotope shifts. We have shown that both effects considerably influence shift and width of Cu i line at 5105.54 Å, and shifts of Cu i lines at 5153.24 and 5218.20 Å.

scholarly journals Theoretical transition probabilities, radiative lifetimes and Stark broadening parameters of singly ionized magnesium

2019 ◽  
Vol 490 (2) ◽  
pp. 1734-1737
Author(s):  
C Moreno-Díaz ◽  
A Alonso-Medina
Keyword(s):  
Transition Probabilities ◽  
Principal Quantum Number ◽  
Stellar Atmospheres ◽  
Spectral Lines ◽  
Atomic Data ◽  
Stark Broadening ◽  
Asymptotic Dependence ◽  
Radiative Lifetimes ◽  
Ionized Magnesium ◽  
Effective Principal

ABSTRACT The presence of spectral lines of singly ionized magnesium (Mg ii) in stellar atmospheres has been reported in different stars. Recently, the low-resolution spectrum obtained from Supernova 2014 J in M82, in which Mg ii absorption lines centred on 4400 Å as well as 7600 Å stand out, has been analysed. This is the motive for the atomic data calculations in this work, which are of much interest in the astrophysical area. In this article, ab initio relativistic Hartree–Fock calculations in an intermediate coupling formalism using Cowan’s code allowed us to obtain the required transition probabilities to calculate the theoretical radiative lifetimes for excited nS−, nP−, nD− and nF− states of singly ionized magnesium. An asymptotic dependence of lifetime (τnl) on the effective principal quantum number (n*) has been determined. Also, the Griem semi-empirical approach was used to obtain the theoretical Stark parameters (width and shift) of spectral lines; these data are displayed for an electron density of 1017 cm−3 and temperatures T = 10–100 (×103 K). We have compared the results of lifetimes for 16 levels and Stark parameters for seven spectral lines with previously reported experiments available in the literature. Finally, we discuss the behaviour of the Stark parameters versus temperature for three relevant spectral lines (2802.70, 2797.99 and 7868.04 Å).

Stark Broadening of Cr II Spectral Lines in Stellar Atmospheres

2007 ◽  
Author(s):  
Milan S. Dimitrijević ◽  
Tanya Ryabchikova ◽  
Zoran Simić ◽  
Luka Č. Popović ◽  
Miodrag Dačić ◽  
...  
Keyword(s):  
Stellar Atmospheres ◽  
Spectral Lines ◽  
Stark Broadening

scholarly journals Comparisons and Comments on Electron and Ion Impact Profiles of Spectral Lines

2011 ◽  
Vol 20 (4) ◽  
Author(s):  
Sylvie Sahal-Bréchot ◽  
Milan S. Dimitrijević ◽  
Nebil Ben Nessib
Keyword(s):  
Neutral Atom ◽  
Molecular Data ◽  
Stellar Atmospheres ◽  
Spectral Lines ◽  
Stark Broadening ◽  
Spectroscopic Diagnostics ◽  
Data Centre ◽  
Ion Impact ◽  
And Shifts ◽  
The Impact

AbstractStark broadening theory is currently operated for calculating widths and shifts of spectral lines that are needed for spectroscopic diagnostics and modeling in astrophysics, laboratory and technological plasmas. We have calculated a great number of data, obtained through the impact semiclassical perturbation theory: tables have been published for neutral atom and ion emitters, and typical temperatures, electron and ion densities. They are currently implemented in the STARK-B database which participates in the European effort within the Virtual Atomic and Molecular Data Centre. Despite of that, a great number of data are still missing. In the present paper, we revisit and compare a great number of the impact Stark widths and shifts by considering their semiclassical perturbation expressions. We also provide fitting formulae which are essential for the modeling codes of stellar atmospheres and envelopes.

scholarly journals Stark Broadening of Co II Lines in Stellar Atmospheres

Data ◽  
2020 ◽  
Vol 5 (3) ◽  
pp. 74
Author(s):  
Zlatko Majlinger ◽  
Milan S. Dimitrijević ◽  
Vladimir A. Srećković
Keyword(s):  
Spectral Line ◽  
Effective Temperature ◽  
White Dwarf ◽  
Semiempirical Method ◽  
Stellar Atmospheres ◽  
Spectral Lines ◽  
Surface Gravity ◽  
Type Star ◽  
Half Maximum ◽  
Stark Broadening

Data for Stark full widths at half maximum for 46 Co II multiplets were calculated using a modified semiempirical method. In order to show the applicability and usefulness of this set of data for research into white dwarf and A type star atmospheres, the obtained results were used to investigate the significance of the Stark broadening mechanism for Co II lines in the atmospheres of these objects. We examined the influence of surface gravity (log g), effective temperature and the wavelength of the spectral line on the importance of the inclusion of Stark broadening contribution in the profiles of the considered Co II spectral lines, for plasma conditions in atmospheric layers corresponding to different optical depths.

scholarly journals Stark Broadening of Several Ne II, Ne III and O III Spectral Lines for the Stark-B Database

2011 ◽  
Vol 20 (4) ◽  
Author(s):  
Milan S. Dimitrijević ◽  
Andjelka Kovačević ◽  
Zoran Simić ◽  
Sylvie Sahal-Bréchot
Keyword(s):  
Data Center ◽  
Molecular Data ◽  
Stellar Atmospheres ◽  
Spectral Lines ◽  
Stark Broadening ◽  
Visible Part

AbstractIn order to complete Stark broadening data for Ne II and O III lines, needed for analysis of stellar atmospheres, we determined the missing parameters for the broadening by collisions with protons and ionized helium for 15 Ne II and 5 O III multiplets. Also, electron, proton and ionized helium impact broadening parameters for an important Ne II multiplet in the visible part of the spectrum and for three Ne III multiplets were calculated. The obtained data will be included in the STARK-B database, which is a part of the Virtual Atomic and Molecular Data Center.

scholarly journals Stark broadening parameter tables for Ne II and Ne III spectral lines

2001 ◽  
pp. 57-70 ◽  
Author(s):  
M.S. Dimitrijevic
Keyword(s):  
Stellar Atmospheres ◽  
Spectral Lines ◽  
Stark Broadening ◽  
Semiclassical Approach ◽  
Line Widths ◽  
And Shifts

Using a semiclassical approach, we have calculated electron-, proton-, He II-, Mg II-, Si II- and Fe II-impact line widths and shifts for 10 Ne II and 6 Ne III multiplets as a function of temperature and perturber density. For Ne II temperatures are: 5,000 K; 10,000 K; 20,000 K; 30,000 K; 50,000 K and 100,000 K and perturber densities from 1015 cm-3 up to 1020 cm-3. For Ne III temperatures are: 20,000 K; 50,000 K; 100,000 K; 200,000 K; 300,000 K and 500,000 K and perturber densities from 1017 cm-3 up to 1021 cm-3. Perturbers selected here, are the main perturbers in solar and stellar atmospheres.

scholarly journals Stark broadening parameter tables for neutral calcium spectral lines. I

1999 ◽  
pp. 35-74 ◽  
Author(s):  
M.S. Dimitrijevic ◽  
S. Sahal−Bréchot
Keyword(s):  
Stellar Atmospheres ◽  
Spectral Lines ◽  
Stark Broadening ◽  
Semiclassical Approach ◽  
Line Widths ◽  
And Shifts

Using a semiclassical approach, we have calculated electron?, proton?, He II?, Mg II-, Si II- and Fe II-impact line widths and shifts for 189 Ca I multiplets as a function of temperature. Perturbers selected here, are the main perturbers in solar and stellar atmospheres.

scholarly journals The Semiclassical Limit of the Gailitis Formula Applied to Electron Impact Broadening of Spectral Lines of Ionized Atoms

Atoms ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 29
Author(s):  
Sylvie Sahal-Bréchot
Keyword(s):  
Electron Impact ◽  
Classical Limit ◽  
Semiclassical Limit ◽  
Spectral Lines ◽  
Stark Broadening ◽  
Feshbach Resonances

The present paper revisits the determination of the semi-classical limit of the Feshbach resonances which play a role in electron impact broadening (the so-called “Stark“ broadening) of isolated spectral lines of ionized atoms. The Gailitis approximation will be used. A few examples of results will be provided, showing the importance of the role of the Feshbach resonances.

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