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Stark broadening of spectral lines of multicharged ions of astrophysical interest - XVI. S V spectral lines

Using a semiclassical approach, we have calculated electron-, proton-, and He III-impact line widths and shifts for 34 S V multiplets for perturber densities and temperatures . For lower perturber densities, the obtained results are linear with perturber density.

The electron impact broadening parameters in hot star atmospheres: Mn II, Mn III, Ga III, Ge III and Ge IV lines

The electron - impact line widths and shifts for 16 Mn II, 3 Mn III, 10 Ga III, 8 Ge III and 14 Ge IV multiplets, have been considered within a modified semiempirical approach. Moreover, using a semiclassical approach, we have considered electron-, pro ton-, and He III-im pact line widths and shifts for 3 Ge IV multiplets. The obtained results have been compared with other...

Stark broadening of spectral lines of multicharged ions of astrophysical interest - XV. P IV spectral lines

Using a semiclassical approach, we have calculated electron-, proton-, and He III-impact line widths and shifts for 114 P IV multiplets for perturber densities and temperatures . The obtained results have been compared with results obtained by using various simpler approaches.

Stark broadening of neutral zinc spectral lines

Using the semiclassical perturbation approach, we have calculated electron-, pro ton- and He II-impact line widths and shifts for 32 Zn I multiplets as a function of temperature and perturber density. Obtained results have been compared with the existing theoretical and experimental data.

Stark broadening of spectral lines of multicharged ions of astrophysical interest - XVIII. Si XI and Si XIII spectral lines

Using a semiclassical perturbation approach, we have calculated electron-, pro ton-, and He III- im pact line widths and shifts for 4 Si XI multiplets for perturber densities 1018- 1023 cm-3 and temperatures K, and for 61 Si XIII multiplets for perturber densities 1016- 1023 cm-3 and temperatures K. For lower perturber densities, obtained results are linear with perturber density.

Stark broadening of spectral lines of multicharged ions of astrophysical interest - XV. P IV spectral lines

Using a semiclassical approach, we have calculated electron-, proton-, and He III-impact line widths and shifts for 114 P IV multiplets for perturber densities and temperatures . The obtained results have been compared with results obtained by using various simpler approaches.

Stark broadening of Sr I spectral lines

Using a semiclassical approach, we have calculated electron-, proton-, and ionized helium-impact line widths and shifts for 33 Sr I multiplets for perturber densities 1013 cm-3 (for stellar plasma research) and 1015- 1018 cm-3 (for laboratory plasma research) and temperatures T = 2 500 - 50 000 K.

Stark shifts and transition probabilities within the Kr I spectrum

On the basis of 28 experimentally determined prominent neutral krypton (Kr i) line shapes (in the 5s–5p and 5s–6p transitions), we have obtained electron (de) and ion (di) contributions to the total Stark shifts (dt). Stark shifts are also calculated using the semiclassical perturbation formalism (SCPF) for electrons, protons and helium ions as perturbers up to 50 000 K electron...

Stark-broadening calculations of singly ionized carbon spectral lines

Using the semiclassical perturbation approach in the impact approximation, we have obtained Stark-broadening parameters for 148 C ii multiplets. Energy levels and oscillator strengths are taken from the TOPbase data base. Results are obtained as a function of temperature for a set of perturber densities of 1014, 1017 and 1018 cm−3. In addition to electron-impact full half widths...

Quantum Stark broadening data for the C iv, N v, O vi, F vii and Ne viii resonance doublets

In this paper, we present new Stark electron impact widths of the 2s–2p resonance doublets of the C iv, N v, O vi, F vii and Ne viii ions, obtained using our quantum mechanical method. The present results are required to develop future spectral analysis using non-local thermodynamic equilibrium model atmospheres, which can make the determination of photospheric properties more...

Electrical conductivity of plasmas of DB white dwarf atmospheres

The static electrical conductivity of non-ideal, dense, partially ionized helium plasma was calculated over a wide range of plasma parameters: temperatures 1 × 104≲T≲ 1 × 105 K and mass density 1 × 10−6 g cm−3≲ρ≲ 2 g cm−3. Calculations of electrical conductivity of plasma for the considered range of plasma parameters are of interest for DB white dwarf atmospheres with effective...

The total and relative contribution of the relevant absorption processes to the opacity of DB white dwarf atmospheres in the UV and VUV regions

The main aim of this work is to estimate the total contribution of the processes of molecular ion photodissociation and collisional absorption charge exchange to the opacity of DB white dwarf atmospheres, and compare this with the contribution of and other relevant radiative absorption processes included in standard models. The method for the calculations of the molecular ion...

Atomic data and electron-impact broadening effect in DO white dwarf atmospheres: Si vi

Energy levels, electric dipole transition probabilities and oscillator strengths in five times ionized silicon have been calculated in intermediate coupling. The present calculations were carried out with the general purpose atomic structure program superstructure. The relativistic corrections to the non-relativistic Hamiltonian are taken into account through the Breit–Pauli...

Stark broadening of Ga I spectral lines

Stark broadening of the 18 Ga I transitions has been analyzed within the framework of the semiclassical perturbation method. Results obtained have been compared with available experimental and theoretical data and used for the consideration of the influence of the Stark broadening effect in stellar atmospheres

Influence of chemi-ionization and chemi-recombination processes on hydrogen line shapes in M dwarfs

Aims.We study the influence of chemi-ionization in collisions and inverse chemi-recombination processes on the population of higher levels and consequently on profiles of hydrogen lines in the atmospheres of late type (M) stars.Methods.Modeling, using general stellar atmosphere code PHOENIX to reveal the importance of the inclusion of such processes.Results.We demonstrate for the...

Stark broadening of the four times ionized silicon spectral lines

Using a semiclassical perturbation approach, we have obtained Stark broadening parameters for 16 Si V multiplets using atomic data calculated ab initio with the SUPERSTRUCTURE code. In order to complete Stark broadening data for the most important charged perturbers in stellar atmospheres, Stark broadening parameters for proton-, He II-, and Si II-impact line widths and shifts...

The influence of H- photo-dissociation and (H + H)- radiative collisions on the solar atmosphere opacity in UV and VUV regions

Aims.To estimate the total contribution of the absorption processes and to the opacity of Solar atmosphere in UV and VUV region, and compare it with the contribution of other relevant radiative processes included in standard models.Methods.The strict quantum-mechanical method was used for the determination of the average cross-section for the photo-dissociation of the molecular...

Stark broadening parameters in singly and doubly ionized fluorine spectra

Stark widths and shifts of 5 singly ionized fluorine (F II) spectral lines within the , and transitions and 5 doubly ionized fluorine (F III) spectral lines within the transition have been measured in a linear, low-pressure, pulsed arc discharge created in SF6 plasma at  K electron temperatures and at  m-3 electron densities. For Stark parameters of two F II and five F III lines...

The flux ratio of the [O iii] λλ5007, 4959 lines in AGN: comparison with theoretical calculations

By taking into account the relativistic corrections to the magnetic dipole operator, the theoretical [O iii] 5006.843/4958.911 line intensity ratio of 2.98 is obtained. In order to check this new value using the active galactic nuclei (AGN) spectra, we present the measurements of the flux ratio of the [O iii] λλ4959, 5007 emission lines for a sample of 62 AGN, obtained from the...

Stark broadening of neutral calcium spectral lines

Using the semiclassical perturbation approach, we have calculated electron-, pro ton-, He II-, Mg II-, Si II- and Fe II-impact line widths and shifts for 189 Ca I multiplets as a function of temperature and perturber density. Perturbers selected here are the main perturbers in solar atmospheres. Obtained results have been compared with the existing theoretical and experimental data.