bluuebunny/crossref_metadata_2025_split huggingface dataset:
24. Commission des Parallaxes Stellaires et des Mouvements Propres
Authors: Mitchell M. S. A. , Adams MM. , Alden  , Bianchi  , Cecchini  , Davidson C. R. , Fox  , Harper  , Horrocks  , Jackson J. , Jones  , Jordan  , Knox-Shaw  , Lee  , Lindblad  , Lockyer  , Luyten  , Miller  , Moffitt  , Nechvíle  , Russell  , Schlesinger  , Shapley  , Slocum  , Smart  , Maanen van , Van Rhijn  , Voûte  
Published: July 2016

In November 1934 the President circulated a letter to the members of the Commission as follows:Since the 1932 meeting the following projects have been completed, or are nearing completion:(1)The publication of many lists of trigonometric parallaxes.(2)The determination of the spectroscopic parallaxes of 4179 stars at Mt Wilson Observatory by Adams, Joy and Humason.(3)A discussion of systematic errors of trigonometric parallaxes by van Maanen and a re-discussion in the Astrophysical Journal of the same material by Mitchell and by Sterne.(4)The compilation of a second Yale Catalogue to include parallaxes completed before the end of 1934.(5)Substantial progress on the proper motions of 32,000 stars by Boss and his associates at the Dudley Observatory.(6)The publication at the Radcliffe Observatory of the proper motions of 32,000 stars from photographs on 115 Selected Areas.(7)The completion of the dynamical parallaxes of 2000 stars.(8)The completion of the proper motions of 18,000 stars derived from parallax plates at the Leander McCormick Observatory.(9)The publication at the Yale Observatory of the proper motions of 40,000 stars with a probable error less than 0”.010 determined from photographs by re-observing in zones the Astronomische Gesellschaft stars.(10)The determination of the proper motions of 50,000 stars in the Southern Hemisphere by Luyten from Harvard photographs.
Commission 12. (Solar Radiation and Solar Spectroscopy.)
Authors: Abetti  , Minnaert M. 
Published: July 2016

The Chairman referred with sorrow to the loss of Dr St John, the former President of the Commission, who died a few months before the meeting.Solar radiation. The President suggested and Prof. Chapman agreed that it would be interesting to make investigations at high altitudes, especially at wave-lengths of about 2100 A.Solar Spectroscopy. Prof. Russell said that the publication of new tables of the infra red solar spectrum would be delayed by the illnesses of Miss Moore and of Dr Babcock.
Commission 19. (Variation of Latitude.)
Authors: Lambert W. D. , Niethammer T. 
Published: July 2016

Dans l’absence de M. Kimura, Président de la Commission, et de son remplaçant, M. Schlesinger, Président de l’Union, prit le fauteuil de présidence.Il constata qu’il était maintenant nécessaire de considérer la question de transférer le siège du Bureau Central à cause de la mauvaise santé de M. Kimura. M. Tanakadate dit que le gouvernement japonais était prêt de continuer les subventions actuelles pour un an de plus, si l’Union le désirait.
Commission 23. (Carte Du Ciel.)
Authors: Esclangon M. E. , Paloque M. E. 
Published: July 2016

M. le Président rend hommage à ceux de ses membres que la Commission a perdus depuis sa précédente réunion: son vénérable et eminent Président d’honneur Benjamin Baillaud, premier Président de l’Union; et Monsieur Gonnessiat qui fut Directeur de l’Observatoire d’Alger.Il souhaite la bienvenue aux membres nouveaux: MM. Donner, Furuhjelm, Nangle, Paloque, H. H. Plaskett, Stein.Il expose l’état d’avancement du Catalogue et de la Carte, fait ressortir que, malgré les progrès réalisés depuis la réunion de Cambridge, il reste encore beaucoup à faire et insiste sur l’importance qui s’attache à l’achèvement des travaux dans les délais les plus réduits.
12. Radiation and Structure of the Solar Atmosphere
Authors: Gnevyshev M. N. , Athay R. G. , Delbouille L. , Michard R. , Minnaert M. , Müller E. A. , Pierce A. K. , Suemoto Z. 
Published: July 2016

By action of the Executive Committee of IAU, the report for 1970 is restricted to half the length of the 1967 draft report; the bibliography and the abstracting of work already published are essentially eliminated. The report is no longer to serve primarily as a review of accomplishments between General Assemblies but rather as a report of work in progress. These changes were adopted by the Executive Committee in order to reduce the cost of publishing the reports.Several commission members have voiced the opinion that the extensive bibliographies in past reports have been the most valuable contributions of the reports and they have objected to the elimination of the bibliography. Also, material from some observatories and from some national groups that have been submitted for inclusion in this draft report have contained only abstracts of work already published. The rules adopted by the Executive Committee do not permit the report to abstract published works except in evaluating general progress in solar astronomy. We express our regret to these commission members and to these institutions that we have not been able to include the abstracts and bibliography in the present report.
21. Light of the Night-Sky
Authors: Huruhata M. , Elsässer H. , Dufay (†) J. , Ingham M. F. , Lebedinskij (†) A. , Roach F. E. , Weill G. , Weinberg J. L. 
Published: July 2016

Studies of airglow, zodiacal light, and galactic light in this triennium were almost as active as in the last. Results of observations obtained during and after the IQSY were the major contributions in this term. Night Airglow studies during the IQSY were widely reviewed in the Annals of the IQSY, vol. 4, in which the following articles are included:“Night Airglow Observations during the IQSY” (F. E. Roach, L. L. Smith and J. R. McKennan);“Airglow Research during and since the IQSY” (G. Weill);“Hydrogen and Hydroxyl Emissions in the Nightglow” (N. N. Shefov and Yu. L. Truttse).Proceedings of the NATO Advanced Study Institute, July 29-August 9,1968, entitled Atmospheric Emissions, contains some ten significant papers on airglow both in observations and interpretations. Many of them are referred to in the following sections.Many stations have been engaged in airglow observations since the beginning of the IASY in 1969, although the number of stations seems to be a little less than during the IGY. Stations near the equator and in the southern hemisphere, however, are more numerous and active than during the IGY in response to the strong wishes of many airglow researchers. These efforts are being made especially by G. Weill’s group of France, V. J. Dachs’ and Lange-Hesse’s groups of Germany.
26. Étoiles Doubles
Authors: Couteau P. , Dommanget J. , Eggen O. J. , Kulikovsky P. , Muller P. , Strand K. Aa. , Van de Kamp P. 
Published: July 2016

On constate que dans l’ensemble les observations classiques se font en quantité égale à celle de 1964 à 1967. Les observations photographiques sont plus nombreuses.De nouvelles méthodes de mesure sont essayées et détectent des couples inaccessibles aux méthodes classiques. Nous citerons par exemple les observations photoélectriques d’occultation de binaires par la Lune (Rakos), les mesures d’intensité interférométrique par comptage de photons (Twiss). Dans les deux cas des séparations très inférieures à 0”01 sont mesurées. Ces travaux semblent ouvrir la voie à une génération nouvelle de moyens d’observations de binaires.
42. Photometric Double Stars
Authors: Wood Frank Bradshaw , Plavec M. , Batten A. H. , Herczeg T. , Kitamura M. , Larsson-Leander G. , Merrill J. E. , Cesevič V. P. 
Published: July 2016

This report differs from earlier ones because financial limitations require the length to be half that of the preceding one. Thus, bibliographical lists are severely limited and it has not been possible to refer to all published papers or to much of the unpublished work. It is hoped that a more extensive mimeographed report will be available to commission members and others interested by the time of the 1970 General Assembly.For invaluable aid in preparing this report, I am deeply indebted to Drs. Batten, Herczeg, Katherine Kron, Larsson-Leander, Merrill, Plavec, and Cesevič. Most of these wrote sections of the report which appear only slightly altered to prevent duplication or to take account of very recent developments. Since it was necessary to review more than 1400 papers which appeared during the three-year interval, obviously this could not have been written without extensive collaboration. I am especially indebted to Drs. Merrill and Plavec for consultation in the difficult choice of matters to be eliminated.
Comparison of Hipparcos Proper-Motion System to the FK5
Authors: Zhu Zi , Jin Wenjing 
Published: July 2016

AbstractWe present an intensive analysis of the FK5 proper-motion system via the two large astrographic catalogs, the PPM and ACRS catalogs, compared with the Hipparcos proper motions. Regional, magnitude, and color-dependent systematic errors in the PPM and ACRS proper motions are found, and exhibit similar tendencies for both catalogs. The term of the global rotation between the FK5 and Hipparcos proper-motion systems cannot be explained by the constant of the FK5 precessional correction, which is given by the VLBI and LLR observations. Comparing the Hipparcos proper motions with those of the SPM 2.0 Catalog, which provides absolute proper motions of objects measured directly relative to external galaxies, we found neither strong systematic nor large regional errors between the two systems.
Stellar Kinematics from Hipparcos Proper Motions
Authors: Zhu Zi , Jin Wenjing 
Published: July 2016

AbstractFrom Hipparcos proper motions, we have analyzed the local kinematics of the Milky Way from the young 0-B5 stars, classical Cepheids, and the late-type K-M giants. Comparing the derived results, the kinematical discrepancies between each subset of stars have been analyzed, and the possible reasons for the kinematical differences have been discussed.
Geodetic and Geophysical Applications of High Precision Astrometry
Authors: Wilson Clark R. 
Published: July 2016

AbstractHigh precision astrometry has a long history of making fundamental contributions to geodesy and geophysics extending centuries into the past, and has provided the foundation for many exciting developments in geophysics in the last several decades. In the 1970s, geodetic VLBI and laser ranging provided the first direct measurement of plate tectonic deformation of the crust. These techniques have also revolutionized the study of Earth rotation by providing sufficient precision to measure climate variability, internal structure, and physical properties. Astrometry will continue to be important in a variety of geophysical problems because of its unique ability to determine Earth orientation relative to a stable celestial frame.
Estimation of EOP from VLBI: Direct Approach
Authors: Petrov L. 
Published: July 2016

AbstractThe currently adopted strategy of EOP estimation from VLBI is to estimate six parameters: UT1, UT1 rate, pole positions and nutation offsets for each 24-hour session independently. Then the resulting time series of raw Earth orientation parameters are filtered and a regression analysis is performed in order to obtain nutation coefficients, polhode of the pole and other physical parameters. Thus, the latter parameters are obtained indirectly in two stages. An alternative approach of direct estimation of the final Earth orientation parameters is presented. Pole coordinates and UT1 are considered as a sum of three components: the low-period component which is modeled by a cubic spline, the harmonic component which includes forced nutation, precession and sub-daily variations of EOP, and the stochastic component which is modeled by a linear spline with segment length 1-2 hours. All parameters are obtained in a single LSQ solution using all available data.
Time and Standards — An Overview
Authors: Guinot Bernard 
Published: July 2016

AbstractAfter recalling current performances of time and frequency standards and their use to establish time scales, their limitations in astronomical observations and studies are considered. For expressing the value of almost all quantities, the accuracy of the frequency standards is sufficient. However, an improved stability could find applications in observation techniques and the departure of realized time scales with respect to their theoretical counterparts is not negligible for some studies. The paper recalls the basic rule of quantity calculus and advocates its use in spite of its inadequacy to express difference of readings of time scales. In general, adherence to the metrological practice and the use of the SI may facilitate our work and its understanding by the non-astronomers.
The Future of Space Astrometry
Authors: Johnston Kenneth J. 
Published: July 2016

AbstractThe future of space-based astrometric missions appears to be very promising. Three missions were described at IAU Colloquium 180. These are the Full-sky Astrometric Mapping Explorer (FAME), the Space Interferometry Mission (SIM) and the Global Astrometric Interferometer for Astrophysics (GAIA) missions. These missions will substantially improve the accuracy of global astrometric measurements made by the Hipparcos space mission by factors of 20 to 250. A brief summary of these projects is given.
Variability Observations of a Complete Sample of Flat-Spectrum Radio Sources: Preliminary Results
Authors: Gorshkov A.G. , Konnikova V.K. , Mingaliev M.G. 
Published: July 2016

AbstractThis report presents preliminary results of daily observations, over 60 and 100 days, of a complete, flux-limited sample of radio sources with flat spectra. The existence of flicker up to 21.7 GHz was confirmed, for sources with flat spectra, on a time-scale of 4 days. A model explaining the flux density variations of the unique radio source 0524+034, on long and short time-scales, by an intrinsic mechanism is proposed.
The Microarcsecond Quasar J1819+3845: Polarization Observations and Detailed Lightcurve Analysis
Authors: de Bruyn A.G. , Dennett-Thorpe J. 
Published: July 2016

AbstractThe quasar J1819+3845 shows exceedingly rapid variations in both total intensity and linear polarization. These are attributed to interstellar scintillation. The source contains at least two structural components each of which shows variable polarization behaviour. The polarization variations are generally, but perhaps not always, coherent over the 80 MHz band setting. The 6 cm lightcurves in the first few months of 2000 hint at a time-asymmetric behaviour as could be expected from an asymmetric source structure.
Toward Solving the Mysteries of the Exotic Eclipsing Binary є Aurigae: Two Thousand years of Observations and Future Possibilities
Authors: Guinan Edward F. , DeWarf Laurence E. 
Published: July 2016

AbstractThe long period (P = 27.1 yr) eclipsing binary є Aurigae (F0 Ia + disk?) is truly an exotic star. It has a deep eclipse that lasts for nearly two years. This eclipse arises as a huge, cool, flattened disk transits the F-supergiant star. Modeling of the eclipse observations shows that the disk has a radius as large as ∼ 9 AU. Infrared observations indicate that the disk is cool with temperatures between 450 − 1000 K. Yet there is evidence of significant FUV emission also originating from the disk.At present, our knowledge of the mass and luminosity of the binary is still too uncertain to distinguish between two competing models of the system. The high mass model assumes that the F0 supergiant is a normal Pop. I star with a mass appropriate for its spectral type of M ∽ 15 M⊙. It is accompanied by a flattened disk companion with a slightly smaller mass. In this model the disk object is a young proto-stellar or protoplanetary disk. In the low mass model, the F0I star is assumed to be a bloated, old, solar mass post-AGB star. In this case the secondary object is an accretion disk with a mass of 4-5 M⊙. This disk is a remnant of postmain sequence mass transfer that occurred within the last few thousand years. In both models there are still problems explaining the object (or objects) at the center of the disk. Candidates include a pre-main sequence object, a black hole, or a close binary.In this paper we review the properties of ϵ Aurigae and discuss the advances in our understanding of this enigmatic star from observations made since its last eclipse in 1982-1984. With new technologies and advanced instrumentation it is possible that the physical properties of this puzzling binary star will be found during the next decade. Once found, then ϵ Aurigae and its eclipses can be used as a laboratory for exploring (and testing) current astrophysical concepts and theories that include rapid stages of stellar evolution, binary star evolution, and the structure and dynamics of large disks.
Irradiation Effects in Compact Binaries
Authors: Beer Martin E. , Podsiadlowski Philipp 
Published: July 2016

AbstractIrradiation of the secondaries in close binary systems affects their appearance and can drastically change their internal structure and hence long-term evolution. In this paper we review the main effects of external irradiation in close binaries with compact primaries, such as the distortion of the shape of the secondary and the conditions for the occurrence of outer critical configurations, and apply these to normal X-ray binaries, including systems such as HZ Her/Her X-l, Vela X-l and black-hole binaries during outburst (e.g. Nova Sco). Particular emphasis will be given to the role of circulation driven by the external heating and the radiative surface stress. We have developed a three-dimensional fluid dynamics code for modelling these effects. We present initial results of self-consistent calculations for the circulation in irradiated systems and show how the inclusion of these effects is vital to the understanding and interpretation of any system where external irradiation of the secondary is significant.
A Protoplanetary Disk in V645 Cyg As Seen with H2O and Methanol Masers
Authors: Val’tts I.E. , Slysh V.I. , Voronkov M.A. , Migenes V. 
Published: July 2016

AbstractRadio images of maser spots in the infrared source RAFGL 2789, connected with the young stellar object V645 Cyg, have been obtained as a result of radio interferometric observations of the H2O maser at 22 GHz and the methanol maser at 6.7 GHz, with the VLBI arrays VLBA and EVN. It is shown that the position of the masers coincides with the optical object within 02. The maser spots are located along the line North-South, and their position and radial velocity can be described by a model of a Keplerian disk with a maximum radius of 40 AU for the H2O maser and 800 AU for the methanol maser. The H2O and methanol maser spots have not been resolved, and lower limits of the brightness temperature are 2 × 1013 K and 1.4 × 109 k respectively. A model of the maser is suggested in which the maser emission is generated in extended water and methanol envelopes of icy planets orbiting the young star.
The Initial–Final Mass Relation for Close Low–Intermediate-Mass Binaries (Non-conservative Case)
Authors: Chen Xuefei , Han Zhanwen 
Published: July 2016

AbstractEmploying Eggleton’s stellar evolution code, we carry out 150 runs of non-conservative Population I binary evolution calculations with the initial primary mass between 1 and 8 M⊙, the initial mass ratio q = M1/M2 between 1.1 and 4 and the onset of Roche lobe overflow (RLOF) at the early, middle or late Hertzsprung gap. We assume that 50 per cent of the mass lost from the primary during the RLOF is accreted on to the secondary, the other 50 per cent is lost from the system, carrying away the same specific angular momentum as the centre of mass of the primary. We find that the remnant mass depends on when the RLOF begins in the Hertzsprung-gap and the dependency increases with the primary mass. The remnant mass, however, does not depend much on the initial mass ratio, as compared to conservative cases. For qi = 1.1, we fit a formula for the remnant mass as a function of the initial mass M1i of the primary and the radius of the primary at the onset of RLOF with an error less than 2.61 per cent.
The Low State Temperature Distribution and First Chemical Abundances of White Dwarfs in Polars
Authors: Sion Edward M. 
Published: July 2016

AbstractDuring the low optical brightness states of AM Her systems (polars) when accretion has declined to a very low value, the underlying magnetic white dwarf photosphere can be modelled without the complication of thermal bremstrahlung and cyclotron emission from the luminous accretion column. The far ultraviolet spectra can be modelled with high gravity Solar composition photospheres. In this way, I present new temperatures and the first chemical abundance estimates for the white dwarfs in three selected polars from the IUE NEWSIPS archive. For the white dwarf in V834 Cen with Teff = 16,000K, Si/H = 0.1 Solar, C/H = 0.5 Solar, for BY Cam, Teff = 17,000K, Si/H = 0.1, C/H = 5 Solar and for RX J1313-32, Teff = 22,000K, Si/H = 0.1 Solar, C/H = 0.1 Solar. The temperature distribution of 24 white dwarfs in polars with known temperatures above and below the period gap is compared with the distribution of the white dwarf temperatures in dwarf novae during quiescence. In both cases, the magnetic white dwarfs in polars are significantly cooler than the non-magnetics. For all CV white dwarfs, magnetic and non-magnetic with Teff < 12,500K, 91% of the objects (10 out of 11) are magnetics in polars. This suggests that long term accretion heating and cooling of white dwarfs in polars differs from the effects of long term accretion in non-magnetic disk accretors.
VY Sculptoris stars are Magnetic Cataclysmic Variables
Authors: Lasota Jean-Pierre , Hameury Jean-Marie 
Published: July 2016

AbstractWe show that VY Scl stars must be magnetized in order to account for the absence of outbursts during their low and intermediate states. Absence of outbursts during low states requires only rather low magnetic moments but in systems in which the drops and rises of luminosity are slower than it takes for the accretion disc to adjust viscously to the variation in mass-transfer rate preventing outbursts require magnetic moments of Intermediate Polars. We discuss some evolutionary aspects of this conclusion.
The XMM-Newton-MSSL survey of Polars
Authors: Ramsay Gavin , Cropper Mark 
Published: July 2016

AbstractThe XMM-Newton-MSSL survey of polars is a snapshot survey of nearly 40 polars. We present the initial results, with an emphasis on the energy balance in these systems and the number of systems which were observed in a low accretion state. In contrast to the ROSAT results we find that the vast majority of polars show no ‘soft X-ray excess’. We find that half of our sample were observed in low or off accretion states. We find no evidence that these systems were biased towards certain orbital periods.
High Speed Keck Spectroscopy of Flickering in AM Her
Authors: Skidmore Warren , Gomer Richard , Horne Keith , O’Brien Kieran , Oke B. , Pearson K. J. 
Published: July 2016

AbstractWe present fast (72ms) spectroscopy of AM Her obtained at an intermediate brightness state just before a rise to a high state. Interesting features in the line behaviour of AM Her are noted and the variability spectrum is presented and compared to that of SS Cyg.
Discovery of 15-second Oscillations in HST observations of W Sge following the 2001 Outburst
Authors: Araujo-Betancor S. , Knigge C. , Marsh T. R. , Hynes R. I. , Steeghs D. , Long K. S. 
Published: July 2016

AbstractWe report the discovery of 15 s oscillations in HST/STIS far-UV spectroscopic observations of WZ Sge in decline, one month after the start of its 2001 outburst. We discuss the implications of this finding for both the magnetic and pulsating white dwarf models that have been proposed to account for the 28 s oscillations.
XMM observations of the long period polar V1309 Ori
Authors: Schwarz Robert , Reinsch Klaus , Burwitz Vadim 
Published: July 2016

AbstractWe present the first full-orbit X-ray light curve of the remarkable eclipsing magnetic Cataclysmic Variable V1309 Ori obtained with XMM-Newton. The photometric behaviour and the extreme soft-to-hard flux ratio of the bright phase emission suggest that accretion occurs entirely via dense blobs.