By taking into account relativistic corrections to the magnetic dipole operator, the theoretical [OIII] 5006.843/4958.511 line intensity ratio of 2.98 is obtained. In order to check this new value using AGN spectra we present the measurements of the flux ratio of the [OIII] λλ4959, 5007 emission lines for a sample of 62 AGN, obtained from the Sloan Digital Sky Survey (SDSS) Database and from published observations. We select only high signal-to-noise ratio spectra for which the line shapes of the [OIII] λλ4959,5007 lines are the same. We obtained an averaged flux ratio of 2.993 ± 0.014, which is in a good agreement with the theoretical one.
Using a semiclassical approach, we have calculated electron-, proton-, and He II-impact line widths and shifts for 52 Be III multiplets as a function of temperature and perturber density. The electron temperatures are 10,000 K 20,000 K; 50,000 K; 100,000 K 200,000K and 300,000 K and perturber densities are from 10(exp)11 cm(exp)-3 up to 10(exp)21 cm(exp)-3.
We present an analysis of 3D spectra of Mrk 533, observed with the integral‐field spectrograph MultiPupil Fiber Spectrograph (MPFS) and using the Fabry‐Perot Interferometer (FPI) of the Special Astrophysical Observatory of the Russian Academy of Sciences (SAO RAS) 6‐m telescope. We found emissions of gas from the active type 2 Seyfert nucleus in the centre and also from the H ii regions in a spiral structure and a circumnuclear region. The gas kinematics shows regular non‐circular motions in the wide range of galactocentric distances from 500 pc up to 15 kpc. The maps of inward and outward radial motions of the ionized gas were constructed. We found that the narrow‐line region (NLR) is composed of at least two (probably three) kinematically separated regions. We detect a stratification in the NLR of Mrk 533 with the outflow velocity ranging from 20–50 km s−1 to 600–700 km s−1, respectively, on the radial distances of ∼2.5 and ∼1.5 kpc. The maximal outflow velocity comes from the nucleus and corresponds to the position of the observed radio structure, which is assumed to be created in an approaching jet. We suggest that these ionized gas outflows are triggered by the radio jet intrusion in an ambient medium.
Aims. We consider the effect of Stark broadening on the shapes of Cr ii spectral lines observed in stellar atmospheres of the middle part of the main sequence. Methods. Stark broadening parameters were calculated by the semiclassical perturbation approach. For stellar spectra synthesis, the improved version synth3 of the code synth for synthetic spectrum calculations was used. Results. Stark broadening parameters for Cr ii spectral lines of seven multiplets belonging to 4s − 4p transitions were calculated. New calculated Stark parameters were applied to the analysis of Cr ii line profiles observed in the spectrum of Cr-rich star HD 133792.Conclusions. We found that Stark broadening mechanism is very important and should be taken into account, especially in the study of Cr abundance stratification.
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