bluuebunny/crossref_metadata_2025_split huggingface dataset:
Latitude Star System of the ILS and the Conventional International Origin
Authors: Sato K. , Wako Y. 
Published: July 2016

AbstractThe essential characteristics of the methods of finding declination corrections for the observed latitudes of the International Latitude Service (ILS) are discussed in the paper.As the z term always includes the errors in the adopted mean latitudes of the stations, the declination system corrected by the z term method is not an absolute one but is internally consistent as it is in the case of the chain method. This method, however, can exclude the proper motion errors which introduce an error in the secular motion of the mean pole.The adopted mean latitudes of the ILS stations which define the CIO should equally be corrected by an amount of(for the epoch of 1961.0), which was inferred from declination errors in the preliminary AG catalogue with reference to the Melchior-Dejaiffe catalogue.
1.1.5 Star Counts in the Background Sky Observed from Pioneer 10
Authors: Tanabe H. , Mori K. 
Published: July 2016

AbstractStar counts in the sky region observed by Pioneer 10 at 4.64AU from the sun, where the contribution of zodiacal light is negligible, were made using the Palomar Sky Survey Atlas. Brightness of the integrated starlight derived from our star counts agrees, in general, with the Pioneer 10’s observation.
1.1.15 The Thermal Emission of the Dust Corona During the Eclipse of June 30, 1975
Authors: Léna P. , Viala Y. , Hall D. , Soufflot A. 
Published: July 2016

AbstractObservations of the F-corona have been made in the 10 µ region of the infrared during the eclipse of June 30, 1973. Use of the supersonic aircraft “Concorde 001” permitted 74 min of observation during totality and greatly reduced problems due to sky noise. The plane of the ecliptic was scanned over heliocentric distances of from 3 to 19 solar radii off the east limb. Bright features previously observed at shorter wavelengths, notably emission at 4 solar radii are evident on the 10 µ scans, strongly indicating that the radiation is due to thermal emission by dust. The specific intensity in the 4 R⊙ feature is 5 µ W cm−2 sterad−1 µ−1; higher than the intensity 22 arcmin above the ecliptic. Spectra were taken at one region in the ecliptic and tentatively attributed to silicate-type material. Complete details may be found in Astron. & Astrophys. 37, 75-79 and 81-86, 1974.
1.1.16 The Color Characteristics of the Earth-Moon Libration Clouds
Authors: Roach J. R. 
Published: July 2016

AbstractThe 0S0-6 Zodiacal Light experiment has provided evidence for the backscatter of light from the Earth-Moon libration regions at 5000 A. Additional measured data at 4000 A and 6100 A show similar characteristics. The combined three-color data lead to libration region color indices slightly bluer than the average surrounding sky background. The differential b-v for the L4 region is approximately −0.05.
1.1.18 Presentation of Zodiacal Light Instrument Aboard the D2B Astronomical Satellite
Authors: Maucherat M. , Cruvellier P. 
Published: July 2016

AbstractThe french astronomical satellite D2B is to be launched on September 1975. During the dial of the orbit, one axis of the satellite points to the Sun, with an accuracy of ± 30 arcmin; during the night of the orbit, the satellite keeps this stabilization by gyroscopic effect. The perpendicular axes -one of them is the optical axis of the Z.L. (Zodiacal Light) instrument- roll around the Earth-Sun direction, once every 4 minutes. Because of the Earth’s motion around the Sun, the celestrial sphere will be scanned along ecliptic meridians, every orbits; the complete exploration of the sky will be achieved after six months. The Z.L. instrument is a photometer analyzing galactic and zodiacal fluxes, in the range λλ 3100-750, in five spectral intervals 200-500 wide, with a field of 2.8°□. For a single scan, the limit of detection by the instrument will be the 6th visual magnitude for early-type stars (0-B).
1.2.3 Scattering in the Earth’S Atmosphere: Calculations for Milky Way and Zodiacal Light as Extended Sources
Authors: Staude H.J. 
Published: July 2016

AbstractThe results of detailed calculations on first order Rayleigh- and Mie-scattering in the Earth’s atmosphere illuminated by the Milky Way and the Zodiacal Light are presented. The influence of various independent parameters, as optical depth of the Rayleigh- and Mie-component and position of Milky Way and Zodiacal Light, is discussed. Linear and circular polarization of the scattered light are considered. The results are compared uith the procedures commonly applied in reducing photometric observations of extended sources of the night sky. It is shown that a substantial part of the discrepancies between the brightness distributions of Zodiacal Light resp. Milky Way given by different authors is due to an inaccurate treatment of the atmospheric scattered light.
5.1 Sources of Interplanetary Dust
Authors: Whipple Fred L. 
Published: July 2016

AbstractAttention is centered on cosmic dust measures made by sensors on Pioneers 8 and 9 in Earth-like orbits. The conclusion follows Zook and Berg that the particles are largely “β-meteoroids,” interplanetary impact debris expelled by solar radiation pressure. An analysis of periodic comet orbits and comets observed during the missions failed to yield correlations, except possibly for debris from Comet Encke. A treatment of β-meteoroids from this stream is presented.
5.4 Orbital Evolution of Circum-Solar Dust Grains
Authors: Lamy Ph. 
Published: July 2016

AbstractThe orbital evolution of circum-solar dust grains is obtained by numerical integration of the equations of motion which includes the grains’ interactions with the solar radiation field and the solar wind. Our past solution (Lamy, 1974) is improved by avoiding a classical approximation for the Poynting-Robertson term and leads to an important revision of the orbital behaviour. Results are presented for obsidian grains whose inward spiraling is stopped by the effect of sublimation.
Multiplicity of Solar-Type Stars
Authors: Abt Helmut A. 
Published: July 2016

AbstractA systematic search for binaries in a sample of 123 bright field stars of types F3-G2 IV or V is described. Combination of the results for 25 newly discovered spectroscopic binaries with those of 21 spectroscopic, 23 visual, and 25 common-proper-motion pairs previously known brings to 88 the total number of companions identified in the sample. The distribution of the 88 periods shows a single maximum; the median period is 14 years.The frequencies of singles: doubles: triples: quadruples are found to be 42: 46: 9: 2. Less than half of the stars are thus observed to be single. Estimates of the completeness of this search lead to a determination of the number of systems missed and to a determination of their secondary masses.Analysis of the secondary-mass distributions, observed and predicted from completeness estimates, indicates the existence of two types of binaries.For systems with periods less than about 100 years, the distribution of secondaries varies with the cube-root of the secondary mass. These systems must be the result of fission. Two-thirds of their primaries have companions of stellar mass. Extrapolation of the cube-root relation implies that the remaining one-third of the primaries have non-stellar secondaries, i.e., close companions whose masses are less than 0.07 solar masses.For systems with periods larger than roughly 100 years the distribution of secondaries follows that given by the van Rhijn function. They must be the result of condensations that contracted separately but are bound gravitationally. Roughly three-fourths of all primaries in the sample have such distant companions, all of which are likely to be themselves close fission-systems. Evidently single stars are rare among solar-type dwarfs.
Etoiles Multiples Et Amas Ouverts
Authors: Dommanget J. 
Published: July 2016

AbstractIt is generally suspected that multiple systems and galactic clusters are objects of different kinds. Their frequency distribution as a function of the number of components, n, as well as their sizes and their masses, show important differences between both categories and also the probable existence of a limit lying between n = 10 and n = 20 components. The basic difference between these objects seems to be that the multiple systems finally appear to be components of the stellar medium in th same way as single and double stars, whereas the galactic clusters are groups of components of a particularly dense part of this medium.
The Stein 2051 System
Authors: Strand K. Aa. 
Published: July 2016

AbstractAn investigation is currently being made of the parallax, proper motion, orbital motion, and mass ratio of the nearby binary star Stein 2051 [04h 11m.4, + 58°49’; (1900); mv = 11.08 and 12.44] based upon photographs taken with the Sproul Observatory 61-cm refractor, the 155-cm astrometric reflector of the U.S. Naval Observatory, and the 33-cm Vatican Carte du Ciel astrograph.A parallax of 0”185 reduced to absolute has been obtained from the material of the Sproul and Naval Observatories which covers the period 1965 to 1975.Since an arc of only 64° in the orbital motion of the visible components has been described from the 1908 epoch of the earliest Vatican plate, and since the separation has increased from 6.” 3 at that time to 7.“ 3 at present and still on the increase, the period of the orbit can only be roughly estimated to be in excess of 300 years.With all plates measured in the same reference frame it has been possible to determine the individual motions of the two components and the mass ratio between them. Preliminary results indicate a perturbation in the orbital motion of the red component with a period of 20 years and a semi-major axis of 0’.’065. The mass ratio between the red dwarf system and the white dwarf is 0.5.A mass of 0.22 M⊙ of the red component has been determined based upon comparison of its luminosity (Mv = 12.42) with the red dwarfs Krüger 60 A (Mv = 11.82), o2 Eri C (Mv = 12.73) and Krüger 60 B (Mv = 13.48) which have the same spectral type (M4) and known masses of 0.26, 0.19, and 0.16 respectively in units of solar masses. Its dark compainion has a mass of 0.02 M⊙ The white dwarf of spectral type DC and Mv = 13.78 has a mass of 0.48 M⊙ as determined from the mass ratio of 0.5 mentioned above.
A Review of the Dynamics of Classical Triple Stars
Authors: Harrington R. S. 
Published: July 2016

AbstractFour ways of studying the dynamics of triple systems are outlined, namely the analytical, the qualitative, the numerical, and the observational approach. A discussion of the stability of classical (revolutional, hierarchical) triples summarizes the results of analytical developments, based on the application of von Zeipel’s method to the general three-body problem, and of numerical experimentation. Finally, a summary is given of recent investigations concerning the dynamics of triples other than the revolutional systems.
Thoughts on the Form of Presentation of Star Catalogue Data
Authors: Eichhorn H. 
Published: July 2016

AbstractThe reductions of the direct measurements necessary for obtaining the published positions and proper motions of stars are rather involved. The transformation from equatorial coordinates to galactic coordinates – and proper motion components – is rather simple, and due to the exact definition of the galactic system, galactic coordinates and proper motion components can be given with the same accuracy as equatorial ones. Since it is data in the galactic system which are primarily of interest for the galactic astronomer, it is proposed that much data be henceforth published in catalogues of star positions and proper motions. One may assume that the minority of astronomers who need the data in the equatorial system will be least likely to make mistakes in transforming them back to the more direct form in which they were observed.It is further suggested that the SAOC could be used as a base for continuous improvement and updating of a comprehensive catalogue of star positions, to be updated by the incorporation of newly available material every other year or so. Procedures by which this would be accomplished are indicated.
The Catalogue of Stellar Identifications
Authors: Ochsenbein F. , Egret D. , Bischoff M. 
Published: July 2016

Collecting all the data and references for a given star is generally a very time-consuming task, because the star may have many identifications. It is therefore a very first need to know the various identifications which may be used in the primary literature concerning a given star, in order to retrieve the whole set of information about the star.The Catalogue of Stellar Identifications (CSI), which tries to solve this problem of cross-identifications, is therefore the fundamental file of the Stellar Data Center. It was created five years ago by J. Jung (1971), who was the first Director of the Center, with the help of Madame Bischoff and Madame Morin. The CSI was first a merging of some fundamental catalogues: SAO, HD, AGK2, CPC (Cape Photographic Catalogue for 1950), YZ (Yale Zone Catalogue), and GC. For each star, the information was the following:
The Influence of Acquisition Techniques on the Compilation of Astronomical Data
Authors: Westerhout Gart 
Published: July 2016

With the increasing use of electronic rather than photographic data collection, and on-line minicomputers at the telescope, two factors will necessitate a reconsideration of the way in which data are stored at the telescope.1) Many of the electronic data collecting methods produce data in a final or semifinal (digital) form and usually with a large dynamic range; high-data-rate digital recording devices at the telescope are increasingly necessary.2) Minicomputers allow quality control of data and often complete data reduction either in real time or with a very short time delay. We shall consider both these factors in some detail, emphasizing some of the many possibilities inherent in the increasing availability of one- and two-dimensional array detectors and mass storage devices. But let us first briefly examine the “classical” data gathering techniques. As in the later discussion, we shall subdivide the field into high-resolution spectroscopy, low-resolution spectroscopy (including multicolor photometry), surface photometry of extended objects, and positional astronomy.
Data Storage Requirements in Relation to Radio Interferometry Observations
Authors: Walter H. G. 
Published: July 2016

SummaryPreliminary results of a search for observational data of radio sources are presented. Emphasis is put on those items which are imperative to make such a data collection amenable to astrometrical exploitation with a view to the identification of optical and radio positions, and the selection of suitable radio stars as reference points for other galactic and extragalactic objects.
The Critical Evaluation of Stellar Data
Authors: Underhill Anne B. , Mead Jaylee M. 
Published: July 2016

AbstractMany catalogues of astronomical data appear in book form as well as in a machine-readable format. The latter form is popular because of the convenience of handling large bodies of data by machine and because it is an efficient way in which to transmit and make accessible data in books which are now out of print or very difficult to obtain. Some new catalogues are prepared entirely in a machine-readable form and the book form, if it exists at all, is of secondary importance for the preservation of the data.In this paper comments are given about the importance of prefaces for transmitting the results of a critical evaluation of a body of data and it is noted that it is essential that this type of documentation be transferred with any machine-readable catalogue. The types of error sometimes encountered in handling machine-readable catalogues are noted. The procedures followed in developing the Goddard Cross Index of eleven star catalogues are outlined as one example of how star catalogues can be compared using computers. The classical approach to evaluating data critically is reviewed and the types of question one should ask and answer for particular types of data are listed. Finally, a specific application of these precepts to the problem of line identifications is given.
Main Features of The Stellar Bibliographic File
Authors: Ochsenbein F. , Spite F. 
Published: July 2016

SummaryDue to the increasing amount of the literature about stellar studies, the gathering of the published information about a given star becomes a tedious and time consuming task. For enabling an automatic retrieval of information, a bibliographic file has been built in machine readable form through collaboration between Paris and Strasbourg Observatories. The file begins with the year 1950, and is kept up to date. Knowing the name of a star, a program prints the titles of the papers quoting this star. However, only the main journals were covered at first, and some other limitations have been imposed. The first part of this file will be very soon published on microfiches. Meanwhile the information can be obtained from the Strasbourg Stellar Data Center, (Centre de Données Stellaires).
Galactic evolution and the interpretation of cosmological tests
Authors: Tinsley Beatrice M. 
Published: July 2016

Resume:L’évolution galactique influence l’interprétation des tests cosmologiques en modifiant les relations entre la magnitude apparente, le diamètre angulaire, le décalage spectral, etc…, prédits par divers modèles. On considère plusieurs tests. Il se peut: (l) que l’évolution stellaire et dynamique dans les galaxies elliptiques rendent ensemble le diagramme de Hubble peu sensible au modèle cosmologique; (2) que la relation éclat-décalage dépende non seulement de l’évolution de luminosité mais aussi de la cosmologie; (3) que les dénombrements de galaxies à magnitude limite démontrent l’évolution galactique et renseignent sur le décalage au moment de la formation des galaxies. En général, les galaxies lointaines renseignent plus sur leur propre évolution que sur le modèle cosmologique.
Anomalous redshifts in groups of galaxies
Authors: Heidmann J. 
Published: July 2016

Nous passons en revue les données d’observation sur les décalages spectraux anormaux dans les groupes de galaxies, incluant les paires, mais laissant de côté les aspects traités par d’autres: associations galaxie-quasar, amas de galaxies et théories.La premiére partie traite des études individuelles sur les paires: paires connectées, compagnons en bout de bras spiral, paires serrées, paires superposées, puis des multiplets et des chaines.La deuxeéime partie traite des études statistiques sur les compagnons des galaxies principales, les paires et les groupes.
Dwarf Galaxies as Low Surface Brightness Galaxies
Authors: Skillman Evan D. 
Published: July 2016

AbstractBecause of the weak correlation between surface brightness and luminosity, as galaxy surveys reach to lower surface brightnesses, increasing numbers of dwarf galaxies are found. Thus, studies of dwarf galaxies are relevant to our understanding of the low surface brightness universe. In particular, studies of nearby LSB dwarfs may help to answer questions concerning: (1) star formation in low abundance and low mass surface density envrionments, (2) star formation histories of galaxies and the relative youth of LSB galaxies, and (3) the chemical evolution of LSB galaxies. HST WFPC2 photometry of the resolved stars in nearby dwarf galaxies is particularly useful for all three questions.H II region abundances remain the best probe of current ISM abundances. Current evidence favors total mass (or luminosity) as the primary factor for determining the present day chemical abundance in both LSB and HSB galaxies. It remains possible that mass surface density (or surface brightness) may be a second controlling parameter.
Gas-rich LSB Galaxies – Progenitors of Blue Compact Dwarfs?
Authors: Salzer John J. , Norton Stuart A. 
Published: July 2016

AbstractWe analyze deep CCD images of nearby Blue Compact Dwarf (BCD) galaxies in an attempt to understand the nature of the progenitors which are hosting the current burst of star formation. In particular, we ask whether BCDs are hosted by normal or low-surface-brightness dI galaxies. We conclude that BCDs are in fact hosted by gas-rich galaxies which populate the extreme high-central-mass-density end of the dwarf galaxy distribution. Such galaxies are predisposed to having numerous strong bursts of star formation in their central regions. In this picture, BCDs can only occur in the minority of dwarf galaxies, rather than being a common phase experienced by all gas-rich dwarfs.
Morphological aspects of star formation in dwarf galaxies
Authors: Brosch Noah , Heller Ana , Almoznino Elchanan 
Published: July 2016

AbstractWe studied the morphology of star formation in dwarf irregular galaxies and found that, in general, this takes place on one side of a galaxy and far from the center. This is mainly true for low surface brightness galaxies; in high surface brightness dwarf irregulars the star formation tends to be more centrally concentrated, as well as being more intense. We discuss possible star formation triggers in dwarf irregular galaxies, and evaluate the reasons for the peculiar distribution of star forming regions of these galaxies. Stochastic star formation, interactions with external gas, and tidal interactions appear to be ruled out as responsible for the asymmetric pattern of star formation. We conclude that asymmetry of a dark matter halo or of an asymmetric underlying stellar distribution may trigger an asymmetric pattern of star formation.
HI in Karachentsev Objects Properties of new nearby Dwarf Galaxies
Authors: Huchtmeier W.K. 
Published: July 2016

AbstractThis is a report on HI observations of newly discovered nearby dwarf galaxies, most of which of low surface brightness, from the first section of the Karachentsev catalog. Observations were performed using the 100-m radiotelescope at Effelsberg, the Nançay radiotelescope, and the compact array of the Australia Telescope. We observed 220 galaxies with a detection rate of about 60%. 35 of the observed galaxies are located within the Local Volume (i.e., within 10 Mpc). The smallest detected galaxies have diameters around 0.3 kpc and HI-masses of a few times 106 solar masses. We confirm a correlation between HI column density and surface brightness of gas-rich disk galaxies.
Using weak Mg II lines to chart Low Surface Brightness Galaxies
Authors: Le Brun V. , Churchill C.W. 
Published: July 2016

AbstractWe report the detection, based on HST and Keck data, of two peculiar absorbers in the Lyα forest of the quasar PKS 0454+039. These clouds, at redshiftsz= 0.6248 and 0.9315 respectively, display both Mg II and Fe II absorption lines in addition to the Lyα line. Based upon photoionization models, these are inferred to be photoionized by the intergalactic UV background, and to have H I column densities in the range 15.8 ≤N(H I) ≤ 16.8. Furthermore, if one supposes that the relative abundances of heavy elements is similar to that of depleted clouds of our galaxy, the abundances of these two absorbers are greater than the solar value, which is a unique case for absorbers which are not associated to the quasar. We tentatively suggest that these absorbers may select giant low surface brightness galaxies.
What We Don’t Know About the Universe
Authors: Impey Chris 
Published: July 2016

AbstractDespite progress on many fronts in cosmology, outstanding questions remain. What is the nature of the dark matter? Is the inflationary big bang model viable? Must we accept a non-zero cosmological constant? Do we know the true population of galaxies? What is the range of star formation histories in the universe? Can gravity alone explain the large scale structure we observe? Studies of the low surface brightness universe may provide the answers to many of these questions.