bluuebunny/crossref_metadata_2025 huggingface dataset:
Plans for A New Edition of the Bright Star Catalogue
Authors: Hoffleit Dorrit , Jaschek Carlos
Published: July 2016

Almost any star catalogue becomes obsolescent as soon as it comes off the press. It is now twelve years since the third edition of the Yale Bright Star Catalogue was published in 1964. In the intervening years numerous important new results have appeared, notably the Jaschek et al Catalogue of MK Spectral Classes, the Lick Double Star Catalogue, the U.S. Naval Observatory Catalogue of UBV Magnitudes, the Abt and Biggs Bibliography of Radial Velocities, the Third Edition and three Supplements of the General Catalogue of Variahle Stars, the SAO Catalogue with proper motions reduced to the FK4 system, several new lists of spectroscopic binaries, and a great many shorter compilations. Consequently well in excess of 20,000 entries in the third edition of the Bright Star Catalogue need up-dating.
Retrieval Techniques and Graphics Displays using A Computerized Stellar Data Base
Authors: Mead Jaylee , Nagy Theresa A.
Published: July 2016

A computerized astronomical data retrieval system, based on the Goddard Cross Index of star catalogs and operable from a remote terminal, has been developed. It permits retrieval of stellar data as a function of the object’s identification numbers, descriptive parameters (magnitude and/or spectral type), or position in the sky. In addition, software has been developed to retrieve the full data entry from any of the eleven catalogs currently included in the Goddard Cross Index, such as the Yale Bright Star Catalog (YBS), the Boss General Catalog (GC), and others all in one computer run.

Four catalogs (Smithsonian Astrophysical Observatory Star Catalog (SAO), The Revised New General Catalogue of Non-stellar Astronomical Objects (RNGC), Reference Catalogue of Bright Galaxies, and Two-Micron Sky Survey) have been sorted by Palomar Sky Survey plate area and precessed to the epoch of the specific plate. For any set of coordinates covered by the Palomar Survey and the Whiteoak Extension, the computer can provide all the plate numbers on which the position can be found. These plate areas can be immediately accessed by computer; listings or plots to any desired scale of any or all of the objects from the four catalogs can be provided.
Survey of Existing Facilities
Authors: Jaschek C.
Published: July 2016

The purpose of the present paper is to present a review of the existing data centers.

If one knows nothing about a subject, one makes an enquiry, and this is exactly what I have done. The list of addresses to start with was provided by Dr. G.A. Wilkins, chairman of the Working Group on Numerical Data of IAU Commission 5, who had collected a list of data services. I want to thank all colleagues who have answered the questionnaire, which is the basis of the present paper; the answers (and the questionnaire itself) are reproduced in Appendix A of this paper.
Dynamics of the Solar Atmosphere Review of Current Observational Investigations in the Visible
Authors: Deubner Franz-Ludwig
Published: July 2016

This review does not attempt to cover the whole range of motions in the solar atmosphere. An extensive review of this more general topic was given in 1975 by Beckers and Canfield, and the interested reader is referred to this paper for some of the items missing in the following presentation.
Structure of the Quiet Chromosphere and Corona
Authors: Gabriel A.H.
Published: July 2016

The scope of this review is limited to include regions from the upper chromosphere above 5 104K out as far as the temperature maximum. The quiet atmosphere is defined as excluding magnetic active regions, but including structures associated with normal supergranule boundaries.
Observational tests in cosmology
Authors: Gunn James E.
Published: July 2016

Nous testons les trois paramètres sans dimension décrivant les modèles cosmologiques de Friedmann: le paramètre de décélération 90, la densité Ωo, et le paramètre temps τo = Ho to. N’importe quel choix de deux de ces paramètres, compte-tenu de l’échelle donnée par la constante de Hubble, décrit un modèle d’univers dans le cadre de la relativité générale avec une constante cosmologique non nulle. L’état actuel des observations et des développements théoriques sont passés en revue. Quelques hypothèses sont proposées. Seuls les tests pour τo sont valables à l’heure actuelle toutefois des doutes subsistent. Les données et l’état de compréhension actuels suggèrent fortement que τo est petit, probablement inférieur à 0.1. Par contre, les tests pour 9o et τo requièrent tous deux de meilleures observations et un gros travail théorique avant de pouvoir espérer des réponses définitives.
Time delay effects for measuring cosmological distances
Authors: Chang K. , Refsdal S.
Published: July 2016

Lorsqu’une galaxie compacte et massive se situe entre un observateur O et une source de lumière S, il se peut que par déflection gravitationnelle, la lumiére suive différents trajets de durées différentes pour parvenir à l’observateur. Si la source est variable il est possible de mesurer la différence de temps Δt entre les durées des trajets. Cela nous donne la possibilité de déterminer les distances cosmologiques d’une façon purement géométrique. Les probléms liés à la distribution inconnue des masses et les possibilités observationnelles sont discutés.
Anomalous redshifts in galaxies and quasars
Authors: Arp Halton
Published: July 2016

Les associations apparentes entre galaxies et quasars sont récapitulées. Les probabilités d'associations accidentelles sont discutées et les relations entre la séparation des quasars et la nature de la galaxie associée sont présentées. De nouveaux cas d'associations apparentes entre galaxies de faible décalage vers le rouge et de grand décalage sont présentés et discutés. Le phénomène des décalages systématiquement plus grands pour les galaxies non elliptiques dans les amas et les groupes de galaxies est abordé. Enfin de récentes évidences sur les galaxies compagnons de M 31 et M 81 montrent que parmi les douze compagnons certains, tous ont un décalage spectral plus grand que la galaxie principale.
The Hubble constant from Tully-Fisher’s relation
Authors: Heidmann J.
Published: July 2016

Nous dérivons la distance de l’amas Virgo et la constante de Hubble à partir de la relation de Tully et Fisher en utilisant les formules de réduction de Heidmann, Heidmann et de Vaucouleurs. Nous trouvons la même valeur que celle de Tully et Fisher et que celle déduite de la relation diamètre-luminosité de Heidmann.
HI observations of interacting groups of galaxies
Authors: Shostak G. S.
Published: July 2016

Nous testons l’idée d’Arp à savoir que des groupes multiples de galaxies en intéraction sont éjectés hors de systèmes brillants proches de nous. Les observations à 21 centimètres indiquent que, si ceci est le cas, les membres du groupe en intéraction ont pour la plupart des masses HI comparables ou inférieures aux galaxies naines, bien que la largeur des raies et la morphologie de ces galaxies suggèrent des masses totales normales. D’autres conséquences de l’hypothèse d’éjection sont brièvement discutées.
Non-cosmological redshifts
Authors: Narlikar J.V.
Published: July 2016

L’introduction de lignes d’univers brisées dans la théorie de la gravitation de Hoyle et Narlikar permet de rendre compte de la création de matière. Cette matière qui se compose de masses inertielles plus petites se manifeste par des décalages spectraux vers le rouge anormaux. Un test basé sur les largeurs de raie est proposé afin de discriminer entre les décalages cosmologiques et les décalages gravitationnels des QSO.
Optical and Near-IR Field Luminosity Functions
Authors: Loveday Jon
Published: July 2016

We present preliminary measurements of the bJ and K-band luminosity functions (LFs) of field galaxies obtained from optical and K-band imaging of a sample of galaxies selected from the Stromlo-APM Redshift Survey. The bJ LF is consistent with that previously published from photographic data. The K-band LF has been estimated over a range of 12 magnitudes and is reasonably well fit by a Schechter function with faint-end slope α = −1.2.
A dichotomy between HSB and LSB galaxies
Authors: Verheijen Marc , Tully Brent
Published: July 2016

A complete sample of spiral galaxies in the Ursa Major cluster is imaged at various optical wavelengths and in the Near-Infrared K′-band. HI rotation curves were obtained for all gas rich systems. The Near-Infrared surface brightness distribution of disk galaxies turns out to be bimodal; galaxies avoid a domain around mag/arcsec2. This bimodality is particularly striking when only the more isolated, non-interacting systems are considered. The Luminosity Function of the HSB family of galaxies is truncated well above the completion limit while the Luminosity Function of the LSB family is still sharply rising at our limiting magnitude. Near-Infrared mass-to-light ratios suggest that HSB galaxies are close to a kinematic maximum-disk situation while LSB galaxies are dark matter dominated at all radii. Assuming equal Near-Infrared mass-to-light ratios for both HSB and LSB systems, we find that the gap in the surface brightness distribution corresponds to a situation in which the baryonic mass is marginally self-gravitating. We finally conclude that the luminosity-line width relation is a fundamental correlation between the amount and distribution of dark matter mass and the total luminosity, regardless of how the luminous mass is distributed within the dark mater halo.
Found: High Surface Brightness Compact Galaxies
Authors: Drinkwater M.J. , Phillipps S. , Jones J.B. , Gregg M.D. , Parker Q.A. , Smith R.M. , Davies J.I. , Sadler E.M.
Published: July 2016

We are using the 2dF spectrograph to make a survey of all objects (“stars” and “galaxies”) in a 12 deg2 region towards the Fornax cluster. We have discovered a population of compact emission-line galaxies unresolved on photographic sky survey plates and therefore missing in most galaxy surveys based on such material. These galaxies are as luminous as normal field galaxies. Using Hα to estimate star formation they contribute at least an additional 5% to the local star formation rate.
HST WFPC-2 Imaging of Four Nearby LSB Galaxies
Authors: O’Neil Karen
Published: July 2016

Between May, 1996 and January, 1997 HST WFPC-2 images of four nearby LSB galaxies were taken through both the 8140Å and 3000Å filters. The first galaxy imaged, UGC 12695, is a nearby (z~0.021) LSB disk galaxy. UGC 12695 has an unusual morphology, consisting of a Y-shaped nucleus surrounded by a faint spiral arm. Additionally, numerous HI regions are spread throughout the galaxy. One of the surprising discoveries with the WFPC2 imaging was that a number of what were previously believed to be structural peculiarities in the galaxy are actually background galaxies. Once the effects of these galaxies are removed, the resultant U—I color of UGC 12695 is only −0.2, making it possibly the bluest galaxy in the local universe. When combined with the metallicity studies of McGaugh (1992), these colors indicate UGC 12695 to be a highly unevolved galaxy.

The other three galaxies imaged - V1L4, V2L8, and V7L3 - are dwarf elliptical galaxies located in the Virgo cluster. The intent of their images was to determine the galaxies’ small scale structure and place limits on the density and type of giant branch stars within each galaxy. Placed at the distance of the Virgo cluster, luminosity fluctuations indicate the galaxies to contain only from 4 – 13 stars per pixel, coinciding with a K/M giant ratio ranging from 6 to ∞ (no M giant stars). Additionally, we found no evidence for stellar clumping in these galaxies although an extremely red, extremely small bulge was found at the core of V2L8.
The star formation histories of Low Surface Brightness galaxies
Authors: Bell E.F. , Bower R.G. , de Jong R.S. , Rauscher B.J. , Barnaby D. , Harper D.A. , Herald M. , Loewenstein R.F.
Published: July 2016

Near-infrared images of a sample of red, blue and giant low surface brightness disk galaxies (LSBGs) were combined with optical data with the aim of constraining their star formation histories. Most LSBGs have strong colour gradients consistent with mean stellar age gradients. We find that LSBGs have a large range of ages and metallicities, spanning those observed in normal disk galaxies. In particular, red and blue LSBGs have very different star formation histories and represent two independent routes to low B band surface brightness. Blue LSBGs are well described by models with low, roughly constant star formation rates, whereas red LSBGs are better described by a ‘faded disk’ scenario.
A new catalogue of multiple galaxies in the Local Supercluster
Authors: Makarov D. I. , Karachentsev I. D.
Published: July 2016

A new approach is suggested which makes use of the individual properties of galaxies, for the identification of small galaxy groups in the Local Supercluster. The criterion is based on the assumption of closed orbits of the companions around the dominating group member within a zero velocity sphere.

The criterion is applied to a sample of 6321 nearby galaxies with radial velocities V0 ≤ 3000 km s−1. These 3472 galaxies have been assigned to 839 groups that include 55% of the sample considered. For the groups identified by the new algorithm (with k ≥ 5 members) the median velocity dispersion is 86 km s−1, the median harmonic radius is 247 kpc, the median crossing time is 0.08(1/H), and the median virial-mass-to-light ratio is 56 M⊙/L⊙.
Dark Matter in Groups and Clusters of Galaxies
Authors: Einasto Jaan , Einasto Maret
Published: July 2016

We compare the characteristics of stellar populations with those of dark halos. Dark matter around galaxies, and in groups, clusters and voids is discussed. Modern data suggest that the overall density of matter in the Universe is ΩM = 0.3 ± 0.1, about 80 % of this matter is nonbaryonic dark matter, and about 20 % is baryonic, mostly in the form of hot intra-cluster and intragroup gas, the rest in stellar populations of galaxies. All bright galaxies are surrounded by dark matter halos of external radii 200 − 300 kpc; halos consist mostly of non-baryonic matter with some mixture of hot gas. The Universe is dominated by dark energy (cosmological constant) term. Dark matter dominates in the dynamical evolution of galaxies in groups and clusters.
Mass Distribution in Compact Groups
Authors: Perea J. , del Olmo A. , Verdes-Montenegro L. , Yun M. S. , Huchtmeier W.K. , Williams B. A.
Published: July 2016

New redshift surveys of galaxies in the field of compact groups have discovered a population of faint galaxies which act as satellites orbiting in the potential well of the bright group. Here we analyze the mass distribution of the groups by comparing the mass derived from the bright members and the mass obtained from the satellite galaxies. Our analysis indicates the presence of a dark halo around the main group with a mass roughly four times that measured for the dominant galaxies of the compact group.

We found that heavier halos are ruled out by the observations when comparing the distribution of positions and redshifts of the satellite galaxies with the distribution of satellites of isolated spiral galaxies. The results agree with a picture where compact groups may form a stable system with galaxies moving in a common dark halo.
Small Satellite Probes of Spiral Galaxies
Authors: Erickson Lance , Gottesman Steve , Hunter James
Published: July 2016

Small, bound satellites of larger spiral galaxies are employed in the determination of the statistical presence of mass beyond the rotation disk of the largest (primary) galaxy. Optical and neutral hydrogen data are combined to develop mass estimates using the small bound groups. The resulting distribution of the internal/external mass ratios provides limits on halo mass models, and a glimpse at this mass estimation technique.
The evolution of groups and clusters
Authors: Gottlöber S. , Klypin A. , Kravtsov A. V. , Turchaninov V.
Published: July 2016

Using high resolution N-body simulations we study the formation and evolution of clusters and groups in a ΛCDM cosmological model. Groups of galaxies already form before z = 4. Merging of groups and accretion leads to cluster formation at z ≲ 2. Some of the groups merge into large isolated halos.
The Visual Absolute Magnitude of the Central Objects in Be Stars
Authors: Moujtahid A. , Zorec J.
Published: July 2016

Using the circumstellar envelope parameters (mean temperature, extent and opacity) derived by fitting theoretical energy distributions to those observed in a sample of 20 Be stars, we estimate the respective magnitude difference ΔV = V – V* of the continuum flux excess produced by their circumstellar envelopes. Using then the HIPPARCOS parallaxes of these stars and the ISM E(B-V) colour excesses derived with the surrounding normal B stars, we estimate the visual absolute magnitude of the central objects in the program Be stars. In most cases the results obtained are in good agreement with the absolute magnitudes obtained from the photospheric (λ1, D) components derived in the BCD spectrophotometric system. There are, however, strong discrepancies in 4 program stars which deserve further studies. The magnitude excess seems to be ΔV ≲ 0 for the higher effective temperatures only. There is no correlation between ΔV and Vsin i, as would be expected if the circumstellar envelopes were strongly flattened.
X-ray Emission from Isolated Be Stars
Authors: Cohen David H.
Published: July 2016

I discuss the X-ray observations of Be stars, and how their properties compare to non-emission B stars. I focus on several specific stars that show high flux levels and variability but also report on several interesting survey results. The Be X-ray properties are discussed in the context of wind-shock X-ray emission from normal OB stars as well as in the context of general mechanisms that have been proposed to explain the Be phenomenon. Finally, I conclude with a discussion of the spectral diagnostics that will be available from the new generation of X-ray telescopes.
Watching Binary Systems with Be Components with the GI2T-REGAIN Spectro-Interferometer
Authors: Thureau N. , Bonneau D. , Mourard D. , Stee P. , Vakili F. , Harmanec P.
Published: July 2016

Our program aims at observing selected bright multiple Be stars using the technique of long-baseline optical spectro-interferometry with the GI2T-REGAIN interferometer. These observations - combined with spectral and photometric observations and with appropriate modelling - will bring new constraints on the nature and evolutionary stage of multiple Be stars through an accurate determination of their basic physical properties.
Multimode Detections from Surveys
Authors: Aerts C.
Published: July 2016

In this study we present an overview of the search for multiple frequencies in variable Be stars from surveys. We review the recent ground-based photometric surveys and conclude from them that multiperiodicity is not detected. The photometric experiment on board Hipparcos, on the other hand, does allow us to derive multiple periods for a few Be stars. We present the results of our frequency searches in the Hipparcos data for 50 λ Eri stars.

Further we review the recent spectroscopic campaigns dedicated to some stars. It seems that all of these campaigns point to multiperiodic phenomena, although for most of them the time base is insufficient to derive the periods with high accuracy. Moreover, the spectroscopic periods are often not the same as those found from the photometry. This clearly demonstrates the necessity of long-term simultaneous photometric and spectroscopic campaigns. We present the preliminary results of such a campaign for the λ Eri star HD 105382.

We close with reflections on the cause of the variability observed in the λ Eri stars and on the best viewpoint for further research in this area.
Fundamental Parameters of Be Stars Derived from Near-Infrared Spectra
Authors: Houziaux L. , Frémat Y.
Published: July 2016

Because of their spectral peculiarities, stellar parameters of objects undergoing the Be phenomenon cannot be determined in the same way as for normal B stars. In particular, the use of the first lines of the Hydrogen series is hampered by the presence of emission components. On the other end, the recently generalized use of CCD detectors, well adapted to the deep red spectral region, provides a large amount of quantitative and well calibrated flux measurements with spectral resolutions around 0.1 nm. We propose to use the shape of the continuum and line flux distribution in the range of the higher Paschen lines of Hydrogen to determine first the effective temperature and superficial gravity of Be stars where, in most cases, the photospheric spectrum is not disturbed by line or continuum emission.
Influence of the Plasma Opacity in the Calculations of IR Emission Due to Dielectronic Recombination of Mg II
Authors: Cruzado Alicia , Ringuelet Adela E.
Published: July 2016

In an earlier work (Cruzado, Di Rocco & Ringuelet, 1998), we showed that the dielectronic recombination of Mg II atoms contributes strongly to the infrared flux. In the present paper we aim at investigating whether the approximations made before could have biased our conclusions.
Continuum Flux Excess in Be Stars Determined from Spectral Lines
Authors: Zorec J. , Ballereau D. , Chauville J.
Published: July 2016

We study the continuum flux excess at λ4471 by comparing the observed He I λ4471 line profiles with non-LTE model line profiles. Assuming that emission of the Hγ line is formed nearly in the same regions of the circumstellar envelope as those where the visible continuum flux excess rises, we estimate the continuum opacity needed to account for the veiling of the He I λ4471 line. The flux excess so derived is then studied as a function of the stellar aspect angle in an attempt to determine the degree of incidence of the envelope geometry near the central star on the continuum flux of Be stars.
Discrete Structures in the CS Envelope of the Be star ζ Tau
Authors: Ballereau D. , Chauville J. , Cao H. , Floquet M. , Hubert A.M. , Zorec J.
Published: July 2016

The recent cycle of the V/R ratio and RV variations in ζ Tau has been found similar to that reported by Delplace (1970). As a rule, in both cycles, singly-ionized metallic shell lines display discrete components when the descending branch of RV curve of Balmer lines crosses the stellar RV value; a narrow sharp feature is mainly superimposed on a broad and bluer one, both being slowly varying over some months; very weak additional components are suspected on stronger Fe II lines. On another hand, in the ascending branch of RV curve (RV ≥ RVstar), secondary shell components varying in intensity are conspicuous on V and R emissions of the first Balmer lines.
Global One-armed Oscillations in the Be/X-ray Binary LS I +61° 235/RX J0146.9+6121
Authors: Reig P. , Negueruela I. , Coe M.J. , Fabregat J. , Tarasov A.E.
Published: July 2016

We present results of our long-term monitoring of LS I +61° 235 in the optical and infrared bands. This Be/X-ray binary exhibits V/R variability in the Hα line, which can be explained in the framework of the Global One-armed Oscillation model: a high density perturbation moves around inside the circumstellar disc of the Be star. The V>R and V<R peaks occur when the perturbation moves towards and away from the observer, respectively. In this work we show that the perturbation also affects the He I λ6678Å and Paschen lines. We also report on a correlation between the infrared emission and the V/R variability.
Confirmation of a Moving Component in the Hα Emission Line of LS I+61°303
Authors: Zamanov Radoslav K. , Martí Josep
Published: July 2016

We report our attempts to detect and confirm a narrow moving component in the Hα emission line of LS I+61°303. The existence of this spectral feature was already suspected in the past. As a result, we find that this component does exist and that its radial velocity varies in agreement with the radio period of the system. We interpret it tentatively as due to a denser region, or bulge, orbiting near the outer edge of the Hα emitting disk.
Pulsar Timing at Urumqi Astronomical Observatory
Authors: Wang Na , Wu XinJi , Zhang Jin , Manchester R. N. , Yusup Aili , Cheng K. S.
Published: July 2016

A pulsar timing system has been set up using the 25-m Nanshan telescope of the Urumqi Astronomical Observatory. It uses a dual polarization receiver operating at 18 cm and a filterbank receiver. The data acquisition system is based on a PC using the Windows NT operating system. Timing properties of about 100 pulsars will be monitored with this system.
Detection of new emission components in PSR B0329+54
Authors: Gangadhara R. T. , Gupta Y. , Lorimer D. R.
Published: July 2016

To study the structure of emission beam, we have analysed the single pulse data of PSR B0329+54 at 325 and 606 MHz. In order to unambiguously detect the weak emission components, we have developed a new data analysis technique, which we term “window-thresholding”. By applying this technique to the data, we have detected three new emission components, and also confirmed the presence of a component which was proposed earlier. Hence our analysis indicates that PSR B0329+54 has nine components, which is among the highest of all the known pulsars. The symmetric distribution of pulse components about the pulse centre, indicates that the emission beam is conal.
Difference and similarity in physics of millisecond and normal pulsars
Authors: Soglasnov V. A.
Published: July 2016

MSP are very similar to NP, but need higher accelerating voltage, because of different emitting agent.
WAPP — Wideband Arecibo Pulsar Processor
Authors: Dowd A. , Sisk W. , Hagen J.
Published: July 2016

The WAPP is a new Pulsar Processor for Arecibo Observatory. Key features are wideband operation (100 MHz) and good time resolution (16 microseconds).
Fine Phase Resolved X-ray Spectroscopy of the Crab Pulsar with BeppoSAX
Authors: Massaro E. , Litterio M. , Cusumano G. , Mineo T.
Published: July 2016

We present the results of a phase resolved spectroscopy of the Crab pulsar in the band 0.1 - 200 keV based on many observations performed with BeppoSAX. The spectrum was found soft in the main peak and significantly harder in the Interpeak region. This behaviour is explained by means of a two component model.
Coherent Mechanisms of Pulsar Radio Emission
Authors: Lyutikov Maxim , Blandford Roger , Machabeli George
Published: July 2016

Relativistic plasma masers operating on the anomalous cyclotron-Cherenkov resonanceω−k||υ||+ωB/ϒres= 0 and the Cherenkov-drift resonanceω−k||υ||−kx/ud= 0, are capable of explaining the main observational characteristics of pulsar radio emission. Both electromagnetic instabilities are due to the interaction of the fast particles from the primary beam and from the tail of the secondary pairs distribution with the normal modes of a strongly magnetized one-dimensional electron-positron plasma. In a typical pulsar both resonances occur in the outer parts of magnetosphere atrres≈ 109cm.
Radiating Regions in Pulsar Magnetospheres: From Theory to Observations and Back
Authors: Usov Vladimir V.
Published: July 2016

We discuss plausible locations of radiating regions in the magnetospheres of pulsars and argue that the mechanisms of pulsar radiation at different frequencies are closely connected with the locations of the radiating regions, especially in the radio range. If the region that is responsible for the bulk of the non-thermal radiation at some frequency is localized in the pulsar magnetosphere then the nature of this radiation will be either determined or, at least, restricted significantly.
Some Peculiaritiers of the Relativistic Electron-Positron Plasma Dynamics in the Pulsar Magnetosphere
Authors: Nanobashvili Irakli S.
Published: July 2016

Some aspects of relativistic electron-positron plasma dynamics in the pulsar magnetosphere are discussed. Namely it is shown that if we take into account the influence of centrifugal force, this gives rise to the new dynamical effect of plasma particle radial braking in the pulsar magnetosphere. Also the possibility of aperiodic instability development in the pulsar magnetosphere is demonstrated. The mechanism for the toroidal magnetic field generation is proposed. Besides, the possible changes of the pulsar magnetosphere structure caused by above mentioned processes is considered.
Kitab as One of the Five Stations of the ILS: History and Present
Authors: Ehgamberdiev Sh.A. , Eshonkulov S.K. , Litvinenko E.A.
Published: July 2016

The Tashkent Astronomical Observatory (Ulugh Beg Astronomical Institute of the Uzbek Academy of Sciences since 1966) was involved to the International Latitude Service (ILS) in September 1899, when the regular latitude measurements were started at Tschardjui (ϕ = +39°08′11″,λ = −63°29′). Because of the Civil War in Central Asia, the latitude observations were ended at Tschardjui in May, 1919. A new latitude station was established at Kitab (Uzbekistan) at latitude ϕ = +39°08′40″ and longitude λ= −66°53′, in November 1930. The Kitab Latitude Station was equipped with two visual zenith telescopes (1929, 1957) and the photographic zenith tube removed from the Pulkovo observatory in 1978. The Kitab station provided the ILS with more than 250000 instantaneous latitude measurements. Since the early 90s Kitab has hosted the ground-based beacons of GPS, PRARE and DORIS satellite tracking systems, providing the IERS data center with precise coordinates at sub daily frequency.
Time and Polar Motion in Early NASA Spacecraft Navigation
Authors: Muller Paul M.
Published: July 2016

Inclusion of Polar Motion and UT1 data (corrections) is essential to achieving the full accuracy in NASA (and other) spacecraft navigation. Tracking station locations are routinely determined to the meter-level and must be available inertially (on the rotating Earth) to equal accuracy a priori in real-time. This implies knowledge of UT1 to 2.5ms and polar motion to lm (and for practical use for the first time accurately predicted and disseminated to the navigation computer programs). This was essential from 1965 onward as we prepared for Apollo, for Apollo itself, and all subsequent missions. This paper presents the history behind the author’s “discovery” circa 1965 at JPL that UT1 and polar motion were not then included in NASA’s Orbit Determination models and programs; how this omission was being “observed” in station location determinations (and errors) from spacecraft radio tracking data; how it was rectified; the essential nature of these data in precision spacecraft navigation including Apollo; and how this became undoubtedly the highest and most critical application of these data in history. There followed widespread recognition of the many observers present and past who tirelessly and often with little visibility outside of professional astronomy made the necessary observations and calculations. As an historical paper, there is room for a few interesting anecdotes and personalities in NASA, as well as the late and much missed Dr. Markowitz then head of the USNO time service, and his successor Dr. Klock, with both of whom the author had the honor, professional benefit, and great personal pleasure of working during this time.
Nature and Properties of the Chandler Motion and Mechanism of its Damping and Excitation
Authors: Ferrándiz J.M. , Barkin Yu. V.
Published: July 2016

The analytical studies of the Chandler motion of the Earth’s pole on the basis of the special approach to the problem, using the canonical and noncanonical equations in the Andoyer elastic variables (Barkin, et al. 1995; Barkin, 1996; in press) have been fulfilled. The Earth is considered as an isolated celestial body with the anelastic (in general case) external envelope (the mantle) and an invariant central part (the core).

The interpretation of the Chandler motion of the body, deformed by its own rotation, was given in the case of an elastic envelope. It was shown that the body rotates as a fictitious rigid body with different moments of inertia. The analytical solution of the problem let us explain the next properties of the motion of the deformable bodies: 1) observed period of the Earth’s polar motion; 2) ellipticity of the pole trajectory and difference of the eccentricities of the Chandler and Euler motions; 3) nonuniform velocity of the counter-clockwise polar motion along the Chandler ellipse; 4) orientation of this ellipse (its minor axis is located in the meridian plane, at 14.5 W degrees).

The influence of the dissipation on the damping of the Chandler polar motion was studied. The analytical solution of the problem was obtained for the simplest treatment of the delay of the tides caused by the Earth’s rotation (Getino & Ferrándiz 1991; Kubo, 1991). This model explains the characteristic behaviour of the amplitude of the Chandler motion in the periods 1905–1920, 1943–1960 (Vondrák, & Cyril, 1966). The excitation of the Chandler motion can be explained by the upper and lower envelope displacements (Barkin, 1999) with Moon-Sun forced attraction with a period of 412 days, close to the Chandler period.
The Oscillation of a System Earth – Moon
Authors: Kurbasova G. , Rykhlova L.
Published: July 2016

Internal links in the Earth-Moon system are determined by gravitational interaction. According to the least compulsion principle of Gauss, the deviation of “free motion” of heliocentric orbits of two material points with Earth and Moon masses is determined by the sum of the products of each material points’ deviation from its free motion and its mass.

By solving the minimization problem using the Lagrange multiplier method, Lagrange equations of the first kind were obtained in vector form. With acceptable assumptions (introduction of non-dimensional time τ = nt, where n is the sidereal rotation of the Moon, and the lunar orbit is considered to be circular) the linkage coefficient (Lagrange multiplier) is:

where v1and v2 are proper frequencies of the Earth and the Moon and μ is the Moon/Earth mass ratio.
The Quality of Sub-daily Polar Motion Estimates based on GPS Observations
Authors: Weber R. , Rothacher M.
Published: July 2016

Since June 1992 the International GPS Service (IGS) has provided time series of its products comprising, among others, very accurate polar motion estimates. While the products of the pilot phase were based on data from about 30 permanent stations, the network now consists of about 140 globally distributed tracking sites (Neilan, 1998).

Several efforts have been undertaken at the CODE Analysis Center of the IGS aiming at the optimization of the global processing strategy, including satellite orbit and troposphere modeling. In addition, the time resolution of the ERP series has been increased to two hours or even one hour. This paper deals with sub-daily polar motion and LOD series of four months in late 1996, which have been calculated in a reprocessing step very recently. The investigations performed allow for comparisons of the new series with results stemming from intensive VLBI tracking campaigns and for the detailed study of the influence of the processing strategy and parametrization on the ERP series.
Multiperiodicity In RRs and & Scuti Stars: An Observational View
Authors: Fitch W.S.
Published: July 2016

On reviewing the observational literature of the recent past on RRs (or dwarf Cepheid or AI Velorum) and δ Scuti stars, it appeared that most present controversy is centered on three specific questions:

(1) Are δ Scuti stars really periodic, or only quasi-periodic?

(2) Are tidal modulations responsible for the slow cyclic variations observed in many of these stars, or not?

(3) Are there any real physical differences between the members of these two groups, or are they actually the same kind of object?

I would like to restrict this review primarily to these questions; and since some of our recent observational results bear directly on questions CI) and (2), and indirectly on question (3), I hope I will be forgiven for describing briefly here some of our current relevant findings.
Discussion Sur Les Resultats De Theories Planetaires
Authors: Bretagnon P.
Published: July 2016

La construction de théories planétaires précises est un travail long et, pour ce qui nous concerne, n’est pas encore achevée. Aussi, les résultats dont nous parlerons ici ne sont que des résultats provisoires. Nous développerons quelques aspects des difficultés que nous avons rencontrées et les conséquences de ces difficultés sur l’orientation des méthodes utilisées pour résoudre les problèmes suivant qu’il s’agit des planètes intérieures ou des grosses planètes.
Improvement of Orbits of Satellites of Saturn Using Photographic Observations
Authors: Sinclair A.T.
Published: July 2016

A programme of photographic observations of the satellites of Saturn, and the method of reduction and analysis are described. The observations have been used to update existing theories of Tethys, Dione, Rhea and Titan. A new theory of the motion of lapetus has been fitted to the observations.
Orbital Stability in the Elliptic Restricted Three Body Problem
Authors: Williams C.A. , Watts J.G.
Published: July 2016

Based on the concept of orbital stability introduced by G. W. Hill, a method is presented to facilitate the determination of the orbital stability of solutions to the planar elliptic restricted problem of three bodies. The invariant relation introduced by Szebehely and Giacaglia (1964) contains an integral which is expanded here about a Keplerian solution to the problem. If the expansion converges, it can be used to determine the conditions for Hill stability. With it one can also define stability in a periodic sense.
Models of AGB Stars Envelopes and Atmospheres
Authors: Forestini M.
Published: July 2016

The possible existence of a hot CN-cycle at the bottom of the AGB convective envelopes (“hot-bottom burning” or HBB) encounters some revealing difficulties with observations (e.g. Reid and mould, 1985). On the other hand, existing models disagree with each other about it.
Pre-Planetary Nebulae and R Corona Borealis Stars
Authors: Schönberner Detlef
Published: July 2016

With the advent of the IRAS satellite a completely new class of stellar objects became evident; viz., objects which are obviously in a rapid transition from the very tip of the asymptotic giant branch (AGB) into the planetary-nebulae region. These so-called pre-planetary nebulae (PPN) are characterized by stellar spectra indicative of supergiants mainly of F and G spectral types in conjunction with a large infrared excess due to a cool circumstellar dust shell. At the same time theoretical calculations through the AGB, with the inclusion of mass loss, and also through the following evolutionary stages down to the white-dwarf sequence, became available (Schonberner 1979, 1983; Wood and Faulkner 1986). These calculations predict evolutionary lifetimes of several 1000 years in the transition region between the tip of the AGB and the planetary-nebulae region. Thus a direct comparison between theory and observation now appears possible in the very early phase of this post-AGB evolution.
Formation of Helium Lines and Continua in a Late-Type Giant Star
Authors: de La Reza Ramiro , Batalha Celso
Published: July 2016

Due to the atomic structure and properties of neutral helium, its spectrum can be an excellent diagnostic of the hot components of the atmosphere of a late-type giant star. Having this in mind, we have studied the formation of the helium lines and continua in the K giant star β Cet. For that purpose different NLTE atmospheric models were constructed. We have also solved the NLTE problem for the formation of lines and continua for a model helium atom consisting of twelve bound levels and three ionized stages.
Relativistic Hierarchy of Reference Systems and Time Scales
Authors: Brumberg V.A.
Published: July 2016

Relativistic hierarchy of reference systems (RS) developed in recent years by different authors is examined in detail. Metric expressions and transformation relations for solar system barycentric RS (BRS), heliocentric RS (HRS), Earth-Moon local RS (LRS), geocentric RS (GRS), topocentric RS (TRS)and Earth satellite RS (SRS) may be obtained explicitly in harmonic coordinates of GRT. The time coordinate of any RS involves the corresponding time scale. Particular attention is given to the closed form representation of GRS avoiding expansions in powers of the geocentric coordinates. GRS has been constructed in both versions of dynamically non-rotating GRS (DGRS) or kinematically non-rotating GRS (KGRS). DGRS and KGRS differ in their space axes orientation by the amount of the geodesic precession. Similarly, taking into account the motion of the Sun around the center of the Galaxy one should distinguish between dynamically non-rotating BRS (DBRS) and kinematically non-rotating BRS (KBRS) differing in their space axes orientation by the amount of the galactic precession. Reduction to the galactic time and the galactic space axes may be needed in the nearest future.
Link between Hipparcos and VLBI Celestial Reference Frames
Authors: Arias E.F. , Lestrade J.-F.
Published: July 2016

The celestial frame of HIPPARCOS astrometric satellite will be materialized by the positions and proper motions of about 120000 stars relative to arbitrary origins. As the HIPPARCOS reference frame is not naturally related to fixed directions in space, it has to be linked to an inertial frame of similar quality. The technique of VLBI determines the coordinates of extragalactic radio sources precise at the milliarcsecond level in an equatorial frame. The precision expected for HIPPARCOS normal mission is 0.002ʺ for the positions, yearly proper motions and parallaxes.
A Global VLBI/LLR Analysis for the Determination of Precession and Nutation Constants
Authors: Charlot P. , Sovers O.J. , Williams J.G. , Newhall X X
Published: July 2016

Two decades of LLR data and one decade of VLBI data are combined in a global analysis to yield improved estimates of the Earth’s precession and nutation. In this analysis, LLR provides a strong determination of precession, while VLBI is stronger in fixing nutation terms with short periods. In all, 24 nutation amplitudes are estimated. The largest correlation coefficient, between precession and 18.6 yr out-of-phase nutation in longitude, is 0.88. With the exception of some 9 yr and 18.6 yr terms, formal uncertainties are 0.1 to 0.2 milliarcseconds.
The Establishment of the Radio/Optical Reference Frame
Authors: Russell J.L. , Johnston K.J. , DeVegt C. , Zacharias N. , Ma C. , Shaffer D. , Jauncey D. , Reynolds J. , White G. , Hughes J. , Hindsley R.
Published: July 2016

This 5-yr program which began in 1987 is to establish a link between the radio and optical reference frames, using about 400 extragalactic sources which are compact and flat spectrum in the radio and which are observable in the optical. An overview of the program is presented at this meeting by Johnston et al. Various specific aspects of it are also discussed in Ma et al., McCarthy et al. and Reynolds et al.

The observations have been continuing in both hemispheres and in both the radio and the optical. We have observed 348 sources with VLBI. There is at least one astrograph plate available for 369 sources and at least one prime focus plate available for 138 sources. Altogether there are 450 sources with some data.
Periodic Variations in the Coronal Green Line Intensity and their Connection with the White-light Coronal Structures
Authors: Minarovjech Milan , Rybanský Milan , Rušin Vojtech
Published: July 2016

We present an analysis of short time-scale intensity variations in the coronal green line as obtained with high time resolution observations. The observed data can be divided into two groups. The first one shows periodic intensity variations with a period of 5 min. the second one does not show any significant intensity variations. We studied the relation between regions of coronal intensity oscillations and the shape of white-light coronal structures. We found that the coronal green-line oscillations occur mainly in regions where open white-light coronal structures are located.
Low Frequency Radio Emission from the ‘Quiet’ Sun
Authors: Ramesh R.
Published: July 2016

We present observations of the ‘quiet’ Sun close to the recent solar minimum (Cycle 22), with the Gauribidanur radioheliograph. Our main conclusion is that coronal streamers also influence the observed radio brightness temperature.
Call K Imaging to Understand UV Irradiance Variability
Authors: Kariyappa R.
Published: July 2016

To identify and understand the underlying physical mechanisms of total solar and UV irradiance variability and to estimate the contribution of various chromospheric features to UV irradiance, detailed analysis of spatially resolved data is required. The various chromospheric features have been segregated and different parameters have been derived from CaII K Spectroheliograms of NSO/Sac Peak and Kodaikanal Observatory and compared with UV irradiance flux measured in MgII h and k lines by NOAA 9 satellite. The important results of this detailed analysis of CaII K Images of 1992 together with UV irradiance data will be discussed in this paper.
The Space Stellar Photometry Mission COROT: Asteroseismology and Search for Extrasolar Planets
Authors: Baglin Annie , Vauclair Gérard ,   the COROT team
Published: July 2016

The main scientific objectives, asteroseismology and search for extrasolar planets for the COROT photometric mission are presented, and its interest in terms of stellar variability. A description of the payload, details of the scientific program, the ground based preparatory observations and bibliography can be found athttp://www.astrsp-mrs.fr/corot/pagecorot.html.
Microwave Enhancement in Coronal Holes: Statistical Properties
Authors: Gopalswamy N. , Shibasaki K. , Salem M.
Published: July 2016

We report on the statistical properties of the microwave enhancement (brightness temperature, area, fine structure, life time and magnetic field strength) in coronal holes observed over a period of several solar rotations.
Frequency Redistribution Effects in the Formation of Lyman α in Prominences and Their Influence on the Ratio of Hα to Lα
Authors: Milkey R.W. , Heasley J.N. , Schmahl E.J. , Engvold O.
Published: July 2016

The effect of partial frequency redistribution in the formation of Lyman α in the chromosphere has been discussed by Milkey and Mihalas (1973) and others, and it has been shown that in this case the coherency of scattering in the wings of the line substantially influences the line profile. Although there are non-negligible sources for La photons within a prominence, a large fraction of the emergent line photons are due to scattering of photons incident on the surface of the prominence so that one expects that in a prominence the frequency redistribution processes will play an important role in determining the emergent intensity.
The Ecology of Prominences
Authors: Zirin H.
Published: July 2016

Why did God create prominences? Surely not simply for the entertainment of solar physicists, although that is an important role. Surely not just as a “solar planetary nebula”, on which we could test radiation models. And certainly not just to help those of us with Hα filters, but no magnetographs, to find the magnetic neutral lines on the sun. Nor were they solely created to be a major source of flares, or to cool off post-flare coronal condensations. In addition to these important roles the prominence must have other organic purposes in the solar scheme. Although I will not be able to tell you these by the end of my talk, I hope you will keep the problem in mind as you listen to me.
Models of Thermodynamic Properties of Prominences
Authors: Milkey R.W.
Published: July 2016

The focus of discussion in Working Group 3 was on the Thermodynamic Properties as determined spectroscopically, including the observational techniques and the theoretical modeling of physical processes responsible for the emission spectrum. Recent advances in observational techniques and theoretical concepts make this discussion particularly timely. It is wise to remember that the determination of thermodynamic parameters is not an end in itself and that these are interesting chiefly for what they can tell us about the energetics and mass transport in prominences.