bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ernst Julius Öpik, Solar Variability and Climate Change
Authors: Sterken C. 
Published: March 2017

Abstract
This paper covers some aspects of the life and work of the Estonian astronomer Ernst Öpik (1893-1985), who contributed to a very wide range of astronomical disciplines, and whose publications span more than 70 years. He worked in Estonia, the Soviet Union, the United States, Germany and Northern Ireland. His visions on the role of solar variability in global climate change are emphasized, and his opinions on modelling in science are explained, in addition to his views about scientific refereeing and publishing.
Tracing Galaxy Evolution by Their Present-Day Luminosity Function
Authors: Tempel E. 
Published: March 2017

Abstract
Galaxy luminosity functions are derived for different morphological types and various colors of galaxies, to trace the evolutionary effects which a priori should be different for void and supercluster galaxies. We also analyse how the galaxy group content changes in the large-scale environment. One of the principal results is the conclusion that the evolution of spiral galaxies is almost independent of the global environment. Meanwhile, the luminosity function of elliptical galaxies depends strongly on the environment. This shows that the global environmental density is an important factor in the formation of elliptical galaxies. The results of the present study clearly show that, except the local/group environment, the global (supercluster-void) environment plays an important role in the formation and evolution of galaxies.
Stark Broadening of Carbon and Oxygen Lines in Hot DQ White Dwarf Stars: Recent Results and Applications
Authors: Dufour P. , Nessib N. Ben , Sahal-Bréchot S. , Dimitrijević M. S. 
Published: March 2017

Abstract
White dwarf stars are traditionally found to have surface compositions made primarily of hydrogen or helium. However, a new family has recently been uncovered, the so-called hot DQ white dwarfs, which have surface compositions dominated by carbon and oxygen with little or no trace of hydrogen and helium (Dufour et al. 2007, 2008, 2010). Deriving precise atmospheric parameters for these objects (such as the effective temperature and the surface gravity) requires detailed modeling of spectral line profiles. Stark broadening parameters are of crucial importance in that context. We present preliminary results from our new generation of model atmospheres including the latest Stark broadening calculations for C II lines and discuss the implications as well as future work that remains to be done.
Stark Broadening of Several Ar I Spectral Lines in the Visible Spectrum
Authors: Dimitrijević Milan S. , Kovačević Andjelka , Simić Zoran , Sahal-Bréchot Sylvie 
Published: March 2017

Abstract
In order to complete data on Stark broadening parameters for Ar I line in the visible spectrum, we determined Stark widths and shifts due to electron, proton and ionized helium impacts for nine lines (4191.0, 4259.4, 5912.1, 6043.2, 6045.0, 6752.9, 7503.9, 7514.6, 7724.2 Å), using jK coupling and semiclassical perturbation theory. The obtained results will enter the STARK-B database, which is a part of the Virtual Atomic and Molecular Data Center.
Stark Broadening of Several Ne II, Ne III and O III Spectral Lines for the Stark-B Database
Authors: Dimitrijević Milan S. , Kovačević Andjelka , Simić Zoran , Sahal-Bréchot Sylvie 
Published: March 2017

Abstract
In 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.
Statistical Analysis of Langmuir Waves Associated with Type III Radio Bursts: II. Simulation and Interpretation of the Wave Energy Distributions
Authors: Maksimović M. , Vidojević S. , Zaslavsky A. 
Published: March 2017

Abstract
We have modeled electrostatic Langmuir waves by an electric field, consisting of superposition of Gaussian wave packets with several probability distributions of amplitudes and with several Poisson distributions of wave packets. The outcome of the model is that the WIND satellite observations, especially in the low frequency domain (the WAVES experiment), do not allow to conclude whether the input wave amplitude distributions are closer to the log-normal than to the Pearson type I or uniform. The average number of wave packets in 1 s is found to be between 0.1 and 50. Therefore, there is a clear need to measure Langmuir wave energy distributions directly at the waveform level, not a posteriori in the spectral domain. This is planned to be implemented on the RPW (Radio and Plasma Wave Analyzer) instrument in the Solar Orbiter mission.
High Energy Emission of Symbiotic Recurrent Novae: RS Oph and V407 Cyg
Authors: Hernanz M. , Tatischeff V. 
Published: March 2017

Abstract
Recurrent novae occurring in symbiotic binaries are candidate sources of high energy photons, reaching GeV energies. Such emission is a consequence of particle acceleration leading to pion production. the shock between matter ejected by the white dwarf, undergoing a nova explosion, and the wind from the red giant companion are responsible for such a process, which mimics a supernova remnant but with much smaller energetic output and much shorter time scales. Inverse Compton can also be responsible for high energy emission. Recent examples are V407 Cyg, detected by Fermi, and RS Oph, which unfortunately exploded in 2006, before Fermi was launched.
Photometric Activity of the Symbiotic Star CH Cyg During 2008–2011
Authors: Shugarov S. , Kolotilov E. , Komissarova G. , Skopal A. , Zemko P. 
Published: March 2017

Abstract
We present results of UBVRC observations of the symbiotic star CH Cyg before and after optical and X-ray bursts in 2009 at various timescales. Rapid variability was found only during a strong burst (U ~ 9.5 mag) in 2009 October, while during the low state, prior to (U ~ 11 mag) and after (U ~ 9.4 mag) the burst rapid variability was not detected.
Telescope and Researcher Potential of Turkey for Collaboration in CV Studies
Authors: Saygac A. Talat , Alis Sinan 
Published: March 2017

Abstract
Turkish astronomical community has witnessed the construction of several telescopes in the last 10 years. These telescopes and the potential of young researchers in the country motivated this poster presentation which aims to receive attention for collaboration in the field of cataclysmic variables and related objects.
Contribution of the Electron Scattering Process to the Broad Hα Wings
Authors: Sekeráš M. , Skopal A. 
Published: March 2017

Abstract
We modeled the extended wings of the OVI 1032, 1038 Å resonance lines and He II 1640 Å emission line in the spectra of Z And, AG Dra and V1016 Cyg by the electron scattering process. By this way we determined the electron temperature and the electron optical depth of the layer of electrons, through which the line photons are transferred in the direction of the observer. We derived an empirical relationship between the emission measure of the symbiotic nebula and the electron optical depth. This relationship allows us to distinguish the flux contribution in the broad Hα wings, which is due to the electron scattering and that produced by the Hα transition in the moving hydrogen plasma. For example, subtracting the electron scattering contribution from the Hα line profile leads to a reduction in the mass-loss rate by approximately 15 %.
On the Symbiotic X-Ray Binary Nature of the Star CGCS 5926
Authors: Masetti N. , Munari U. , Henden A. A. , Page K. L. , Osborne J. P. , Starrfield S. 
Published: March 2017

Abstract
We report on multiwavelength (from X-ray to optical) follow up observations of a carbon star CGCS 5926, motivated by the fact that it is positionally coincident with a faint X-ray source of the ROSAT catalog, thus suggesting its possible symbiotic X-ray binary (SyXB) nature. Our optical spectroscopy confirms that this is a carbon star of type C(6,2). This allows us to infer for CGCS 5926 a distance of ~5 kpc. BVRCIC photometry of the star shows variability of ~0.3 mag with a periodicity of 151 days, which we interpret as due to radial pulsations. the source is not detected with the Swift satellite in X-rays down to a 0.3-10 keV luminosity of ~3 × 1032 erg s−1. This nondetection is apparently in contrast with the ROSAT data; however, the present information does not rule out that CGCS 5926 can be a SyXB. This will be settled by more sensitive observations at high energies.
High-Resolution Spectroscopy of the Hydrogen-Deficient Binary υ Sgr
Authors: Kipper Tõnu , Klochkova Valentina G. 
Published: March 2017

Abstract
The high resolution spectra of hydrogen-deficient binary υ Sgr are analyzed. The atmospheric parameters are Teff = 12300±200 K, log g = 2:5±0:5 and ξt = 5 - 15 kms−1 depending on the element. For Fe II ξt = 9:3 ± 0:3 kms−1. Iron is slightly underabundant (-0.2 dex). Nitrogen is overabundant with [N/Fe]ͬ ≈ 1.0, carbon and oxygen are underabundant with [C/Fe] ≈ -1.6 and [O/Fe] ≈ -1.1. The s-process elements Y, Zr and Ba are overabundant about 0.5 dex. Quite large number of emission lines, both permitted and forbidden, originating from low excitation levels of neutral and ionized metals, are identified. Radial velocities of these emission lines indicate that an accretion disk in the system is present.
Discovery, Observational Data and the Orbit of the Amor Group Asteroid 2010 BT3
Authors: Černis K. , Zdanavičius J. , Wlodarczyk I. , Stonkutė E. 
Published: March 2017

Abstract
A project devoted to astrometric and photometric observations of asteroids at the Molėtai Observatory is described. One of its most important results is the discovery of the asteroid 2010 BT3 belonging to the Amor group of the near-Earth objects. The results of astrometric and photometric observations of the asteroid are presented. The brightness variations of the asteroid are found to be about 0.2 mag in R. The orbit of the asteroid was computed from 96 observations. This orbit, combined with the apparent brightness, gives the absolute magnitude 21.34 mag and the diameter between 160 m and 360 m, taking albedos of S-type and C-type asteroids, respectively.
Cross Catalogue Matching with Virtual Observatory and Parameterization of Stars
Authors: Malkov O. , Dluzhnevskaya O. , Karpov S. , Kilpio E. , Kniazev A. , Mironov A. , Sichevskij S. 
Published: March 2017

Abstract
Virtual Observatory facilities allow users to make a fast and correct cross-matching of objects from various surveys. They yield multi-color photometry data (color indices) on registered objects and make it possible to determine stellar parameters. A method of catalogue cross-matching, as well as its application to various areas in the sky and preliminary results of stellar parameterization, are discussed in the paper. We also make a critical analysis of modern stellar spectral atlases.
Large Astronomical Surveys, Catalogs and Databases
Authors: Mickaelian A. M. 
Published: March 2017

Abstract
We review the status of all-sky and large astronomical surveys and their catalogued data over the whole range of electromagnetic spectrum, from gamma-ray to radio, such as ROSAT in X-ray, GALEX in UV, SDSS and several POSS1/2 based catalogs (APM, MAPS, USNO, GSC) in optical, 2MASS and WISE in NIR, IRAS and AKARI in MIR/FIR, NVSS and FIRST in radio range and others. Present astronomical archives contain billions of objects, Galactic as well as extragalactic, and the vast amount of data in them permit new studies and discoveries. Cross-correlations result in revealing new objects and new samples. Very often, dozens of thousands of sources hide a few very interesting ones that are needed to be discovered by comparison of various physical characteristics. Most of the modern databases currently provide VO access to the stored information. This permits not only open access but also fast analysis and managing of these data.
Spectral Analysis Via the Virtual Observatory: The Service Theossa
Authors: Ringat E. , Rauch T. , Werner K. 
Published: March 2017

Abstract
In the framework of the Virtual Observatory, the newly developed service TheoSSA provides access to theoretical stellar spectral energy distributions. In a pilot phase, this service is based on the well-established Tübingen NLTE Model-Atmosphere Package for hot, compact stars. We demonstrate its present capabilities and future extensions.
Digital Archive of the Astrograph Plates Stored at the Inasan Zvenigorod Observatory
Authors: Vereshchagin S. V. , Chupina N. V. 
Published: March 2017

Abstract
The plate collection of the Zvenigorod 40-cm Carl Zeiss astrograph, obtained in 1972-2003, contains direct photographs of star fields, comets, asteroids, Pluto, and Mars. The electronic library of images from photographic plates was created from scanning the astronomical negatives. We present information on programs scheduled at the telescope and the structure and maintenance of the plate stacks. We also list the plates with images of asteroids and comets. Access to all our plate lists is provided at the web sites of the Institute of Astronomy (INASAN) and WFPDB. It is possible to select plates by the date of observation, by the coordinates of the sky area, by the object type. Preview images can be inspected.
High-Resolution Spectroscopy of Cool Carbon-Rich and Metal-Poor Star HD 209621
Authors: Matrozis E. , Začs L. , Barzdis A. 
Published: March 2017

Abstract
Element abundances for HD 209621 obtained earlier display significant discrepancies, especially in the case of CNO and neutron-capture elements. Therefore we performed a detailed analysis of chemical composition of this star using a new high-resolution spectrum. Atmospheric parameters and abundance pattern are updated, and the mechanism of nucleosynthesis is examined. Abundances for 11 elements are calculated for the first time. The method of atmospheric models and spectral synthesis was used. The following values of atmospheric parameters are derived: Teff = 4400 K, log g = 1.0 (cgs) and ξt = 1.9 kms−1. The iron abundance of the star was found to be low, at [Fe/H] = -1.91±0.10. The carbon to oxygen ratio is high, C/O ≃ +2.0. Low carbon to nitrogen ratio, [C/N] ≃ -0.8, and low carbon isotopic ratio, 12C/13C = 17 ±5, are in agreement with the theory of nucleosynthesis of intermediate-mass AGB stars. The barium to europium ratio is high, [Ba/Eu] = +0.28, and is typical for carbon-enhanced metal-poor CEMP-r/s stars. The observed abundance pattern of neutron capture elements is reproduced well by the scaled solar system abundances.
Photometry and Classification of Stars in the Direction of Clusters NGC 7129 and NGC 7142 in Cepheus. I. Magnitudes, Color Indices and Spectral Types of 2140 Stars
Authors: Maskoliūnas M. , Zdanavičius J. , Zdanavičius K. , Straižys V. 
Published: March 2017

Abstract
In a 1.5 square degree area, centered at RA = 21:44:30, DEC = +65:58, we have determined magnitudes and color indices for 2140 stars in the Vilnius seven-color system down to V = 17 mag. This area includes a star-forming region with the open cluster NGC 7129 embedded in a dense dust cloud TGU 645 (LDN 1181), close to the Cepheus Flare, and a distant old open cluster NGC 7142 seen through a semi-transparent window. For most of the stars spectral and luminosity classes in the MK system, determined from the photometric data, are given.
Variability Survey of Massive Stars in OB-Associations: Preliminary Results on the Cygnus Region
Authors: Laur J. , Tuvikene T. , Eenmäe T. , Kolka I. , Leedjärv L. 
Published: March 2017

Abstract
We present V - and I-passband photometry of massive stars in the Cyg OB1 and Cyg OB2 associations, based on about 80 observing nights spanning 300 days in the 2011 season. The variability of 22 supergiants and 48 OB-stars with luminosity classes III-V is analyzed. We report two new variable OB stars and 15 variable supergiants of which four are new discoveries. The light variations of Schulte 12 are interpreted as microvariability. We also present light curves of the red supergiants BC Cyg and BI Cyg which exhibit brightness drop of more than 0.4 mag during the season.
Modeling the Supply Process Using the Application of Selected Methods of Operational Analysis
Authors: Chovancová Mária , Klapita Vladimír 
Published: March 2017

AbstractSupply process is one of the most important enterprise activities. All raw materials, intermediate products and products, which are moved within enterprise, are the subject of inventory management and by their effective management significant improvement of enterprise position on the market can be achieved. For that reason, the inventory needs to be managed, monitored, evaluated and affected. The paper deals with utilizing the methods of the operational analysis in the field of inventory management in terms of achieving the economic efficiency and ensuring the particular customer’s service level as well.
The Influence of Selected Drying Methods on the Physical Properties of Dried Apples cv. Jonagold Grown in Different Locations in Europe
Authors: Michalska Anna , Lech Krzysztof , Figiel Adam , Łysiak Grzegorz P. 
Published: March 2017

Abstract
The aim of the study was to determine the influence of four different growing locations of apples cv. ‘Jonagold’ in Europe on the drying kinetics and the physical properties of dried apple slices. The drying methods applied in the study (freeze-drying, convective drying, microwave-vacuum drying and combined drying) significantly affected the drying time, which was the shortest in the case of microwave vacuum drying. The geographical origin of the apples affected the chemical and physical properties of the raw material used for drying, and, consequently, the drying time. Water activity of dried samples was connected with the final dry matter, regardless of the geographical origin of the apples. Freeze-drying resulted in the lightest in colour products (L*), whereas microwave-vacuum dried products had the highest levels of yellow pigments (b*). The highest chroma and browning index values were noted for microwave-vacuum dried samples and were strongly influenced by the drying temperature. The mechanical properties of the apple slices were more dependent on the drying method and temperature of the process than on the geographical origin when the temperature exceeded 83 °C.
Analysis of Transmission Characteristics with Improved Modulation Formats Based on ROF Coherent System
Authors: Li Li , Li Zhi-Rui 
Published: March 2017

Abstract
Radio over Fiber (RoF) is one of the solutions to the “last mile” because of its bandwidth advantage offered by fiber and the mobility and flexibility of wireless systems. In this paper, the transmission performance of DSB, SSB and OCS with three modulation formats is established, and a new single-sideband modulation single-mode optical fiber transmission model is proposed, and simulated analysis is done to the system. In this paper, 40 GHz millimeter-wave signal was generated by external modulation, and the received signal is received by coherent demodulation. In this paper, Matlab and VPI are used for combine programming simulation, DCF method was used to compensate the chromatic dispersion. Through the analysis of dispersion performance, Q value and bit error rate, we can see that the modified SSB modulation has the best transmission performance for 120 km links.
A Scheme for UDWDM-PON Broadband Access Network Using a Mode Locked Laser Diode and Optical Injection Locking
Authors: Chakraborty Meenakshi , Chattopadhyay Taraprasad 
Published: March 2017

Abstract
This paper describes an useful scheme of ultra-dense wavelength division multiplexed-passive optical network (UDWDM-PON) meant for the bidirectional transmission of analog video signals to the users in the Optical Network Unit (ONU). Each user has a dedicated wavelength which carries a group of analog video channels. This PON scheme is bidirectional with a long distance of transmission of 100 km typically over a single optical fiber. The video channels designated for a particular user in the ONU can be continuously tuned by a post-detection tunable bandpass filter. Intermodulation distortion (IMD) resulting from a mixing of analog video channels carried by a single wavelength has been calculated for a group of three video channels which lies in the range of –30 dB to –85 dB typically for a set of values of parameters used in practice. This IMD level is fairly acceptable for analog video signal transmission and reception in practice. The novelty of this scheme is that it is long reach.
Research Article. A new gravity laboratory in Ny-Ålesund, Svalbard
Authors: Breili K. , Hougen R. , Lysaker D. I. , Omang O. C. D. , Tangen B. 
Published: March 2017

Abstract
The Norwegian Mapping Authority (NMA) has recently established a new gravity laboratory in Ny-Ålesund at Svalbard, Norway. The laboratory consists of three independent pillars and is part of the geodetic core station that is presently under construction at Brandal, approximately 1.5 km north of NMA’s old station. In anticipation of future use of the new gravity laboratory, we present benchmark gravity values, gravity gradients, and final coordinates of all new pillars. Test measurements indicate a higher noise level at Brandal compared to the old station. The increased noise level is attributed to higher sensitivity to wind.We have also investigated possible consequences of moving to Brandal when it comes to the gravitational signal of present-day ice mass changes and ocean tide loading. Plausible models representing ice mass changes at the Svalbard archipelago indicate that the gravitational signal at Brandal may differ from that at the old site with a size detectable with modern gravimeters. Users of gravity data from Ny-Ålesund should, therefore, be cautious if future observations from the new observatory are used to extend the existing gravity record. Due to its lower elevation, Brandal is significantly less sensitive to gravitational ocean tide loading. In the future, Brandal will be the prime site for gravimetry in Ny-Ålesund. This ensures gravity measurements collocated with space geodetic techniques like VLBI, SLR, and GNSS.
Crystal structure of a diaqua-bis(3,5-di(1H-imidazol-1-yl)pyridine-κN)-bis(2-(4-carboxy-phenyl)acetato-κO]manganese(II), C40H36MnN10O10
Authors: Ju Feng-Yang , Guo Wen-Bo , Li Yun-Ping 
Published: March 2017

Abstract
C40H36MnN10O10, monoclinic, P21/c (no. 14), a = 21.8966(12) Å, b = 7.2586(4) Å, c = 12.2346(6) Å, β = 98.232(1)°, V = 1924.52(18) Å3, Z = 2, R
gt(F) = 0.0327, wR
ref(F
2) = 0.0847, T = 296(2) K.