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Active Galactic Nuclei (AGNs) are powerful energy sources in the Universe, emitting radiation from the gamma to radio spectral range. Different physical processes are present in the emitting plasma around the super-massive black hole, that is supposed to be in the center of an AGN. Here we present an overview of plasma conditions in emitting regions of AGNs. We start from the X-ray emitting region, which is close to the super-massive black hole, discussing the physics and geometry of the region. In more details we discuss the plasma that emits broad emission lines, i.e. the Broad Line Region, and at the end we present methods to determine the plasma conditions in the Narrow Line Emitting Region using forbidden, collisionally excited, emission lines.

We study the Josephson effect and pairing correlations in SFFS junctions that consist of conventional superconductors (S) connected through two metallic monodomain ferromagnets (F) with transparent and spin‐inactive interfaces. We solve the Eilenberger equations for arbitrary relative orientation of magnetizations of the two F layers in the clean limit, and calculate spatial variation of pair amplitudes, singlet fs, and odd‐frequency triplet ft0 and ft1, with 0 and ±1 spin projections, as well as the Josephson current. We find that for the angle 0

The necessity to utilise for physics and science education wider school space than a classroom, has been identified during last decades by many educators. From their side, architects initiated and cordially have been carrying out innovative school design, as well as improvement of learning environment as a whole. By continuing previous research we propose and elaborate a set of out classroom installations which could be useful in science teaching and would provide a stimulating learning environment. We conclude that closer collaboration of science educators, school designers and school investors could be very fruitful and useful. The support of ministries of education is indispensable, too.

Far‐infrared reflection spectra and results of dielectric measurements of SrTiO3: Mn and SrTiO3: Nd crystals are presented in the paper. Dielectric investigations were conducted at temperature range from 25 K to room temperature in the frequency region between 80 kHz and 11 MHz. Far‐Infrared reflectivity spectra have been measured in the wave‐number region from 150 cm−1 to 4000 cm−1 at temperatures 80 K and 300 K. The numerical analysis of the far‐infrared reflection spectra was made by using a fitting procedure based on factorized form of the dielectric function. The obtained results are compared with those for pure SrTiO3 crystal. The lowest‐frequency phonon mode is found to be strongly influenced by presence of neodymium ions in SrTiO3 single crystal.

Active Galactic Nuclei (AGN) are the most luminous objects in the Universe. It is widely accepted that radiation emitted from these objects originates in an accretion disk around a Supermassive Black Hole (SMBH). Emission spectral lines (in the X‐ray and UV/optical) are used to investigate the plasma conditions in the vicinity of the SMBH. Here we give a short overview of the emission line profiles and their usage for determination of kinematics (geometry) of emitting plasma around black hole.

The complex structure and the peculiar profiles of some spectral lines are common in the UV spectrum of AX Mon (HD 45910). The observed peculiar profiles are composed by a number of SACs or DACs. In this paper, using the GR model, we study the complex profile of the Al II (λ 1670.81 A), Al III (λλ 1854.722, 1867.782 A), Mg II (λλ 2795.523, 2802.698 A), Fe II (λ 2586.876 A), C II (λλ 1334.515, 1335.684 A) and Si IV (λλ 1393.73, 1402.73 A) spectral lines. Additionally, we calculate the relation of some kinematical parameters of the regions that create the DACs/SACs of the studied lines with the ionization potential.

In this paper we study the Lyα spectral line and the N V, Si IV and C IV resonance lines in the UV spectrum of the Broad Absorption Line Quasar (BAL QSO) PG 1254+047. We found that the studied Broad Absorption Lines (BALs) of this quasar are created by a number of Satellite Absorption Components (SACs). We calculated some kinematical parameters such as the apparent rotational (Vrot) and radial (Vrad) velocities of the regions where the studied lines are created and the random velocities (Vrand) of the studied ions.

In the UV spectrum of AX Mon (HD 45910) we observe a series of spectral lines with complex structure and peculiar profiles. This peculiarity is due to SACs or DACs. In this paper, using the GR model, we study the complex profile of Fe II spectral lines and we calculate the relation of some kinematical parameters of the regions that create the DACs/SACs with the excitation potential.

In the spectra of Hot Emission Stars and AGNs we observe some peculiar profiles that result from dynamical processes such as accretion and/or ejection of matter from these objects. In this paper we indicate that DACs and SACs phenomena, can explain the spectral lines peculiarity in Hot Emission Stars and AGNs. We also try to connect the physical properties of absorption regions around stars and quasars.

In this paper we study the C IV and Si IV resonance lines in the UV spectrum of the Broad Absorption Line Quasar (BAL QSO) PG 0946+301. The studied Broad Absorption Lines (BALs) are mainly created by a number of Satellite Absorption Components (SACs). However, the C IV doublet of PG 0946+301 is one of the very few lines that present clearly the DACs phenomenon, in the case of quasars. We applied the GR model and we calculated the apparent rotational (Vrot) and radial (Vrad) velocities of the regions where the studied lines are created and the random velocities (Vrand) of the C IV and Si IV ions.

The spectra of Hot Emission Stars and AGNs present peculiar profiles that result from dynamical processes such as accretion and/or ejection of matter from these objects. In this paper we explain the idea of DACs and SACs phenomena, as a reason of spectral lines peculiarity in Hot Emission Stars and AGNs. We present the line function of a kinematical model enabling to study the physical parameters of the density regions in the plasma surrounding the considered objects, where DACs and SACs of a spectral line are created, producing the observed peculiar profiles. We also present some first general conclusions, deriving from the proposed model, including the relations among the physical parameters of the density regions of the plasma surrounding the Oe stars, where DACs and SACs are created, producing the observed peculiar profiles.

Using general stellar atmosphere code PHOENIX, the influence of chemi‐ionization and inverse chemi‐recombination processes, in H*(n)+H(1s) collisions, on the population of higher levels and consequently on profiles of Hydrogen lines in the atmospheres of late type (M) stars was studied. Obtained results are the first demonstration of the possibility to confirm the considered processes influence by direct observations of stellar spectra. It is demonstrated that it is very important to include chemi‐ionization and chemi‐recombination processes in modeling of atmospheres of late type stars, especially if one wants to use line profiles for diagnostics of stellar photospheres and lower chromospheres.

The presence of Satellite Absorption Components (SACs) in the N IV spectral lines of 20 Oe stars of different spectral subtypes were analyzed and the physical parameters which characterize the corresponding N IV density regions were studied. We found that the N IV spectral lines consist of one or two Satellite Absorption Components. We calculate the values of the apparent rotational and radial velocities, the random ion velocities, as well as the Full Width at Half Maximum (FWHM), the absorbed energy and the column density of the independent regions of matter which produce the main and the satellite components of the studied spectral lines. Finally, we present the variations of these physical parameters as a function of the spectral subtype.

Energy levels, electric dipole transition probabilities and oscillator strengths are calculated for Si VI with the general purpose atomic‐structure program SUPERSTRUCTURE. We have also introduced a semi‐empirical correction (TEC) for the calculation of the energy levels. These atomic data are used to provide semiclassical electron‐ and proton‐impact line widths and shifts for five Si VI muliplet.

Here we investigate the asymmetry of the C IV λ 1549 A line in a sample of Radio Quiet (RQ) and Radio Loud (RL) Active Galactic Nuclei (AGN), in order to find signature of an outflow in C IV λ 1549 A emission region. We apply two‐component Gaussian analysis to fit the lines. We consider the parameters of the components (emission and absorption), separately in Radio Loud and Radio Quiet AGN, and we compared those parameters with parameters of the fits of [O III] λλ 4959, 5007 A lines, trying to see if there is any kinematical correlation between the emission regions (HIL BLR and NLR) where C IV λ 1549 A and [O III] λλ 4959, 5007 A lines are formed.

Chemi‐ionization processes, leading to formation of molecular ions, can play an essential role in the sequence of ion‐molecular reactions on surfaces of solid particles or in associative processes of the binary collisions leading to surprising variety of molecular formations in interstellar gas and geocosmical plasmas. The presented results may be recommended for the interpretation of experimental data and for theoretical research of geocosmical plasmas, first of all the the volcanic gases on Io.

Most active galactic nuclei are variable sources in the optical. The delay between variations in their continuum and their emission lines gives us information about the distance of the line emitting region from the central ionizing source. The study of the line profile variations contains information on geometry and kinematics of the broad emitting line gas that surrounds the central supermassive black hole in the nuclei of active galaxies. I present results of a spectral variability campaign of the Seyfert galaxies NGC 5548 and Mrk 110.

We have identified and measured the accurate strengths of Bowen fluorescence lines of O III and N III in the spectra of the Symbiotic Nova RR Telescopii. Altogether 29 O III lines, some of them newly identified, have been measured. After re‐determining the inrestellar absorption, we show that the relative line strengths can be accounted for assuming that the ground state transitions as well as the pumping line of the Fowler He II Lyα have huge optical depths resulting in large broadening wings and significant overlap enhancing the fluorescent efficiency. This is also true for the N III lines where resonance scattering optical depths as large as 106 producing broad wings and pumping by more than one line can produce the observed line ratios. Other methods such as continuum fluorescence or recombination are shown not to be effective.

Using double‐peaked lines and assuming that they are emitted from an accretion disc, it is possible to get impression about accretion disc parameters (inner and outer radius, inclination). Here we will present an analysis of accretion disc parameters obtained from five Active Galactic Nuclei (AGN) with double‐peaked lines from the SDSS. The aim of this work is to connect the disc parameters with other characteristics of the host galaxy.

Accurate pressure broadened profiles of alkali resonance doublets perturbed by helium are needed for modelling of the atmospheres of late M, L and T type brown dwarfs for temperatures up to 3000 K. Previous fully quantum‐mechanical calculations of line widths and shifts are extended to consider the line‐wing profiles where impact theory is no longer valid. Results are presented for the Lorentzian line widths of the lithium, sodium and potassium resonance lines calculated using both impact and one‐perturber theory. Excellent agreement between these two approximations is obtained, demonstrating that quantum‐mechanical calculations of the line profiles can be made that are accurate over the whole range of frequencies from the line centre to the line wings.

We have calculated by using the semiclassical perturbation approach Stark broadening parameters for Cr II spectral lines and used the obtained results to investigate the influence of Stark broadening effect in stellar atmospheres. From our investigation we can conclude that newly calculated Stark widths for a number of strong Cr II lines agree with the scarce laboratory data and provide a good fit to the line profiles observed in Ap stars. New Stark parameters are particular important for the study of Cr stratification in Ap stars in 9000–10000 K temperature region, where this stratification may be obtained from the careful study of the line profiles of multiplet 3 Cr II lines only.

Ionized manganese lines are of interest for the analysis and modelling of stellar spectra as well as for the modelling and consideration of sub photospheric layers. Recently, a disagreement of up to 5.7 times is found between experimental and calculated Stark widths and shifts of Mn II lines. As one of possible reasons, the hfs splitting was assumed. In order to investigate the reasons for this, we performed more sophisticated calculations for two Mn II lines, by using the semiclassical perturbation theory. Moreover, we made a detailed analysis of the influence of hfs splitting on the considered experimental results. Also, the obtained results were used for the investigation of the influence of Stark broadening on Mn II spectral line profiles in DB white dwarfs. It was demonstrated the importance to take into account Stark broadening mechanism for the analysis of DB white dwarf spectra. The obtained data and conclusions are of interest for a number of problems in stellar and Solar physics, like spectrum analysis and synthesis, radiative transfer and modelling of sub photospheric layers.

The shift of three argon spectral lines due to the interactions between the excited atoms and atoms in a ground state has been calculated. These lines belong to one spectral series 3p5nd 2[7/2]4−3p54p 2[5/2]3 for n = 5–7. The dependence of the shift coefficient on gas temperature under atmospheric pressure has been obtained. The semi‐classical impact theory has been applied and Kaulakys potential has been used.

Spectra integrated along the line‐of‐sight are the main source of information about the history of galaxies. The spectral energy distribution, and the strength of selected spectral features allow a first diagnostics of the age and metallicity of stellar systems. The next step of refinement is to analyze the shape of the absorption lines.In the recent years, on one side high S/N observations of galaxies and star clusters at medium spectral resolution (R≈1000–5000) became available. On the other side, models of stellar populations gained in precision. We are presenting here the state‐of‐the art in the spectroscopic analysis of stellar populations.In the center of galaxies, the spectra are the composition of several components: A bulge and a disk; an old stellar population, plus a star formation region or a young population, plus a NLR, a BLR of an active nucleus. We are describing how these composite spectra may be analyzed.

In the present work, we have reviewed and compared our experimental and theoretical Au II Stark widths. The interest in Au II resides not only on the knowledge of its atomic structure, or to check the adequacy of theoretical models, but also on its astrophysical importance because its lines are present in spectra of chemically peculiar stars.The plasma source of Au II spectrum was produced by laser ablation on pure gold, using the Laser Induced Breakdown Spectroscopy (LIBS) technique.The theoretical results were obtained using the modified semiempirical approach. Obtained experimental and theoretical results were compared and discussed, in order to prepare the new measurements and to analyze the astrophysical applications for CP star spectra modelling.

We present in this paper quantum‐mechanical calculations for the electron impact Stark linewidths of the 2s3s–2s3p transitions for the beryllium‐like neon. Calculations are made in the frame of the impact approximation and for intermediate coupling, taking into account fine structure effects. A comparison between our calculations and experimental and other theoretical results showed a good agreement. This is the first time that we find such a good agreement between quantum and experimental linewidths of highly charged ions.

In order to investigate hidden disk emission in the single peaked Broad Emission Lines (BEL) we simulated profiles with simplified model consisted of two components: accretion disk and surrounding spherical region with isotropic velocities of clouds. Then, we measured full widths at 10%, 20% and 30% of the maximum intensity and normalized them to the full width at half maximum (FWHM). We compared these measurements for simulated and observed profiles, of a sample of 25 Seyfert 1, Hα and Hβ emission lines, from SDSS database. We found that for these kind of broad single peaked emission profiles, the disk may be present. In this case the inclination of the disk should be i

A sample consisting of 1040 stars, mainly dwarfs of late spectral types, from the solar neighbourhood is studied. Among various spectroscopic data available for all of them we use the line‐of‐sight velocity and metallicity. A clear correlation between these two quantities is found. Based on it we establish the fractions of galactic subsystems in the sample. It is found: 93% for the thin disc, 6% for the thick disc and 1% for the halo. The halo stars are in the present sample the most easy to be separated, they are the metal‐poorest in the sample. For the thin disc the velocity ellipsoid is determined.

A rigorous selection of ARIHIP stars is done where, among others, only the stars having line‐of‐sight velocity are taken into account. In this way a sample of 4614 stars is obtained. It is studied kinematically to find that the velocity dispersion appears to be dependent of both colour index and limiting distance for a group of stars. In the latter case the ratio of the velocity‐dispersion components is affected.

In addition to optical photometry of unprecedented quality, the Sloan Digital Sky Survey is also producing a massive spectroscopic database: recent public Data Release 6 contains 1.27 million spectra of stars, galaxies, quasars and blank sky selected over 7425 square degrees. I summarize the spectroscopic selection criteria, observing and reduction procedures, data access tools, and provide a few examples of diverse scientific results based on these data.

The new astronomical station at the mountain Vidojevica (ASV) nearby the town of Prokuplje will be finished till the end of 2007. A part of the research at the ASV will be dedicated to the stellar spectroscopy. The Astronomical Observatory in Belgrade provided a spectrograph for this purpose. In the town of Belogradchik in Bulgaria, nearby the Bulgarian‐Serbian border, a small astronomical observatory of the size as ASV is situated and equipped similarly as ASV The aim of this paper is to compare the equipment of these observatories and discuss possible cooperation between them, in particular in those areas of astronomy in which the stellar spectroscopy plays an important role.

Carbonaceous compounds are a significant component of interstellar dust and the composition and structure of such materials is therefore of key importance. We present 1.5 μm‐15 μm spectra of a plasma polymerized carbonaceous material produced in RF discharge under low pressure, using C2H2 as a precursor component. The plasma polymerization process described here provides a convenient way to make carbonaceous interstellar dust analogues under controlled conditions and to compare their characteristics to astronomical observations. Here, we focus on a comparison to the IR spectra of interstellar dust in the light of the criteria for “good” carbonaceous interstellar dust analogue. The UV bump at extinction curve 217.5 nm is another key feature for understanding the abundance of carbon in interstellar media. We present here some preliminary results of UV extinction on plasma polymerized astro‐analogue.

Emission lines in X-ray spectra of clusters of galaxies reveal the presence of heavy elements in the diffuse hot plasma (the Intra Cluster Medium, or ICM) in virial equilibrium in the dark matter potential well. The relatively simple physical state of the ICM allows us to estimate, with good accuracy, its thermodynamical properties and chemical abundances. These measures put strong constraints on the interaction processes between the galaxies and the surrounding medium, and have significant impact on models of galaxy formation as well. This field is rapidly evolving thanks to the X-ray satellites Chandra and XMM-Newton. Among the most relevant progresses in the last years, we briefly discuss the nature of cool cores and the measure of the Iron abundance in high redshift clusters. Future X-ray missions with bolometers promise to provide a substantial step forward to a more comprehensive understanding of the complex physics of the ICM., Comment: 8 pages, 3 figures, Proceedings of the VI Serbian Conference on Spectral Line Shapes in Astrophysics, Sremski Karlovci, Serbia June 11-15 2007

The World Space Observatory UltraViolet (WSO‐UV) is an international space mission devoted to UV spectroscopy and imaging. The observatory includes a single 170 cm aperture telescope capable of high‐resolution spectroscopy, long slit low‐resolution spectroscopy, and deep UV and optical imaging. The observatory designed for observations in the Ultraviolet domain where some of the most important astrophysical processes can be efficiently studied with unprecedented capability.Progress of modem astrophysics requires the access to the electromagnetic spectrum in the broadest energy range. The ultraviolet (UV) is a fundamental energy domain since it grants high sensitivity access to the study of both atomic plasmas at temperatures in the 3,000–300,000 K range and molecular plasmas illuminated by UV radiation since the electronic transitions of the most abundant molecules in the Universe (H2, CO, OH, CS, CO2+, C2…) are in this range; the UV radiation field itself is a powerful astrochemical and photoionizing age...

For the gas temperature determination for a discharge at atmospheric pressure, the ro‐vibrational emission spectra of the molecular species are usually used, but exist cases when it is difficult to detect them. In order to analyze the possibility to use the van der Waals broadening of the neutral‐argon lines to determine the gas temperature in an argon surface‐wave sustained discharge (SWD) at atmospheric pressure, the values of the gas temperature inferred from the atomic lines with that ones obtained from the analysis of the OH molecular specie spectrum, were compared. If the Lorentzian broadening of a spectral line depends on axial position, this line is sensitive to the electron density variation. This is in particular the case for the 522.1, 549.6 and 603.2 nm lines. For this reason, these lines could be used to measure the electron density in discharges at atmospheric pressure. For these spectral lines a linear fit is obtained, which intersects the ordinate at a point corresponding to the Lorentzian width for zero electron density. This value can be considered approximately equal to the van der Waals width and is used here to calculate the plasma gas temperature. From our results and the comparison with other authors we can conclude that the method, proposed in this work, gives a possibility to estimate the gas temperature from the van der Waals broadening of atomic lines.

When plasma is in thermodynamic equilibrium, all species have the same kinetic temperature. In practice, plasmas are generally not in equilibrium, so different temperatures can be obtained. We investigated here temperature dependence of Stark widths for neutral atom spectral lines in order to find a more precise method for scaling with temperature.

We detected the presence of Satellite Absorption Components (SACs) which accompany the C IV resonance lines in the spectra of 20 Oe stars of different spectral subtypes, taken with IUE. The values of the apparent rotational and radial velocities, the random velocities of the thermal motions of the ions, as well as the column density and the Full Width at Half Maximum (FWHM) of the independent regions of matter which produce the main and the satellites components of the studied spectral lines were calculated. The variations of these physical parameters are presented as a function of the spectral subtype.

In the spectra of Oe and Be stars, many spectral lines present peculiar and complex profiles due to the fact that the observed absorption features are composed of two or more absorption components (Discrete or Satellite Absorption Components—DACs/SACs). Here we detected the presence the SACs phenomenon in the C IV, N IV and N V spectral lines in 11 spectra of the Oe star HD 149757 (zeta Oph), taken with IUE during a period of 13 years.

DC high E/N swarm experiment (self sustained discharge operating in the Townsend regime) may be modeled directly and exactly as it does not require self consistent calculation of the electric field and is thus open to a simple Monte Carlo simulation that may include complexity at the level of representation of collisional events. Thus such an experiment operating under swarm conditions is the best way to test the mechanism of generation of anomalously large Doppler broadening that was often observed in low pressure discharges.In this paper we show revised results of modeling of Doppler profiles by using a well tested Monte Carlo procedure and revised models of heavy particle collisions. In particular we study the importance of fast H2 and fast H particles, the effect of different models of angular distribution of particles scattered of the surface and of the molecules and we study the role of the energy losses due to vibrational excitation.

This paper presents a study of the usability of the Coulomb cut‐off potential for the calculation of bound‐free and free‐free cross sections. It covers the condition in dense plasma where there is no good theory that covers the optical properties of dense plasma. The presented quantum mechanical model has given a good agreement with the experimental data. The ideas for further development of the presented calculations are shown.

We present Stark broadening parameters (widths) of 5 multiplets of S II, 3 multiplets of S III and 2 spectral lines of S IV calculated using modified semi‐empirical approach (MSE). Needed atomic data (energy levels) have been calculated ab initio using Cowan code. Comparison of energy levels of S II, S III and S IV calculated by Cowan code and energy levels taken from NIST atomic spectra database is given.

Up to now, all direct observational checks of the theoretical [OIII] 5006.843/4958.511 intensity ratio have been made for photoionized gaseous nebulae spectra. However, in some papers analyzing spectra of quasars, galaxies and AGN, this ratio is obtained as by‐product, used as a checking method or may be derived from published results. Recently, taking into account relativistic corrections to the magnetic dipole operator, Storey and Zeippen obtained the line intensity ratio of 2.98. In order to check that new value using the AGN spectra, we present the measurements of flux ratio of [OIII] λ λ 4959, 5007 A emission lines for a sample of 62 AGN, obtained from SDSS Database and from the published observations. We selected the sample using criteria of high signal to noise ratio and that line shapes of 4959 and 5007 are the same. We found that flux ratio is 2.993 ± 0.014, which is in a good agreement with the theoretical value of 2.98 given by Storey and Zeippen (2000).

A review of the studies concerning the local Milky‐Way kinematics which have used line‐of‐sight velocities of stars is given. This review comprises historical aspects, methodics and perspectives, as well.

In order to analyse the stellar spectra we use the Gauss‐Rotation method and we conclude that the SACs/DACs phenomena are able to explain, in a unique way, the complex and peculiar observed profiles. These results arise from the study of the Mg II (λλ 2795.523, 2802.698 A), SiIV (λλ 1393.755, 1402.77 A), and Hα (λ 6562,817 A) region of a great number of Be stars of all spectral subtypes and luminosity classes (64 in the case of Mg II resonance lines and 70 in the case of Si IV resonance limes). For the study of the regions which create the complex Hα line profiles we analyzed the OHP (Observatory of Haute Provence) spectrographs of 120 Be stars of all spectral subtypes and luminosity classes. We present the evolution of some kinematical parameters from the photosphere to the extreme cool envelope.

I review the theory of broadening of metallic spectral lines by neutral hydrogen atom collisions developed by Anstee, Barklem and O'Mara. I discuss why the theory works, while is able to retain the wide range of applicability needed for astrophysical applications. I discuss the present status of large scale calculations for many spectral lines for neutral and singly ionized species. Some examples of application to analysis of cool star spectra will be discussed.

XMM‐Newton and Chandra observations of quasars suggest the presence of high‐velocity outfiows of ionized absorbing material with mass‐outflow rates of up to a few M⊙ yr−1 that are considerably higher than those based on the wind properties derived from UV BALs. Quasar winds might be more powerful than what we previously thought. X‐ray absorption lines produced by outfiowing material detected in several quasars are possibly probing a highly ionized and high velocity component of the accretion disk wind that appears to be distinct from the absorbers detected in the optical and UV wavebands. We present X‐ray absorption line diagnostics that allow us to constraint the properties of the outfiowing wind in quasars.