bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gamma-Ray Lines from SN1987A and Interpretation
Authors: Chupp E. L. 
Published: June 2019

AbstractGamma-ray lines from the decay of 56Co in the SN1987A remnant have been detected by satellite and balloon experiments. The observations directly confirm the basic theoretical tenet that 56Ni was explosively synthesized in the aftermath of core collapse of the blue super giant Sanduleak – 69 202. The flux level of the 56Co lines at 847 keV and 1238 keV, from the Gamma-Ray Spectometer (GRS) on the SMM satellite, is consistent with a constant level from 1987 August through 1988 May. The early appearence of the γ-ray lines and the continuum reported by the Ginga and Mir-Kvant satellite experiments require mixing, or clumping of a few percent of the newly synthesized 56Ni in the expanding envelope. Results from balloon experiments, which are in the preliminary stage of analysis, do not give clear evidence for γ-ray line shifts from rest energies with a limit ΔE/E < 0.002, nor is there definitive evidence, at this time, of line splitting, but γ-ray line widths are clearly wider than instrument resolution at ΔE/E < 0.02. The continuum (50-500) keV/line ratio has stayed approximately constant at 8 from 1987 August to 1988 May indicating the origin of the continuum from Compton down-scattering of deeper lying 56Co and lines from 56Co at smaller γ-ray optical depths. Future balloon flights of the most sensitive high-resolution spectrometers, planned for 1988 November and 1989 April, are expected to be able to detect weaker γ-ray lines at a flux level of ~ 10-4 γ cm-2 s−1 for the 847 keV line. SN1987A was just close enough to the Earth to confirm theory with existing instruments. In this report we review only γ-ray line results, since the continuum observations have been reviewed by Professor Trümper in this session.
Interpretation of the CO Bands of Supernova 1987A
Authors: Sharp C.M. , Höflich P. 
Published: June 2019

AbstractModel calculations for the interpretations of the CO bands in the IR are discussed. Spherical symmetry is assumed. Profiles of the physical quantities (i.e. temperature, mass, electron density, abundances, etc.) are given by NLTE models which allow for the representation of observed spectra of supernova 1987A in the optical and near infrared. C and O have to be chosen overabundant by a factor of 25 in the helium-rich layers, or a clumpy density distribution structure of a corresponding factor relative to the mean local value is needed. However, the comparison between the observed forbidden OI line at about 6300 A favours the first interpretation. A factor of about 3 has to be taken into account as uncertainty for the overabundance because of the assumptions of the background model. This implies evidence for strong mixing of the helium rich region with more central layers during the stellar evolution and/or the explosion.
NLTE Calculations of Hydrogen Line Profiles for SN1987A
Authors: Schmutz Werner 
Published: June 2019

The synthetic line profiles presented here are the result of a series of models :-Woosley's (1988) calculation of the stellar explosion yield the luminosity, the density and the velocity structure of the expanding SN as a function of time (Woosley's model 10HM was used)-subsequent Monte Carlo simulations of the radiation transport in the expanding photosphere are based on the atmosphere structure given by the model above for a given time. The calculations take into account tens of thousands of lines and yield the line blanketed continuum flux and the temperature structure.-The previous two models specify the physical condition of the expanding shell. With a third model the NLTE populations of 10 H and 12 He levels are determined and the emergent hydrogen lines profiles are obtained. The method of solving the NLTE problem is described by Wessolowski et al. (1988) and references therein.
What we know about Families of Asteroids
Authors: Zappala’ V. 
Published: June 2019

AbstractAsteroid families are considered for the most to represent fragments of collisional breakup of precursor bodies. If true, this offers the unique possibility to examine the interiors of large bodies and to study the processes of collision on a scale much larger than can be done in laboratory. Indeed, the general features of the mass distributions and of the ejection velocities of the family members can be interpreted in terms of collisional disruption of a parent body followed by self-gravitational reaccumulation on the largest remnant. However, several problems remain open: a) the degree of fragmentation in real families is generally lower than that observed for experimental targets; b) the relative velocities computed including also proper eccentricity and inclination differences are higher by about a factor 4 than those derived from semiaxes differences only; c) only very few of the presently proposed families have distributions of inferred mineralogies consistent with cosmochemistry. Further studies are needed, including better proper elements computation, classification methods, and new investigations on the physics of hypervelocity impacts.
The Origin and Physical Characteristics of Meteoroids
Authors: Olsson-Steel Duncan 
Published: June 2019

ABSTRACTRecent investigations of the terrestrial influx of small meteoroids (sizes l00µm–1 cm) are reviewed, and it is shown that (i) Previous radar measurements have underestimated the influx of these bodies by at least an order of magnitude; (ii) The true height distribution of meteors in the atmosphere indicates a very low bulk density, in general of order 0.01-0.10 gm cm-3; (iii) Several Apollo asteroids have associated meteoroid streams, implying a genetic relationship and hence the possibility that these asteroids are in fact extinct or dormant cometary nuclei; and (iv) Along with the other three retrograde intermediate-period comets, P/Halley most likely originated in the Kuiper Cloud of comets just beyond the planetary region, and not in the distant Oort Cloud as is usually assumed.
Ultraviolet, Visible, and Infrared Spectroscopy of Interstellar Molecules
Authors: Black John H. 
Published: June 2019

ABSTRACTAbsorption line spectroscopy in the ultraviolet, visible, and infrared regions can provide important probes of interstellar chemistry. Significant recent developments include the application of optical absorption line techniques to the study of thick molecular clouds and the improvements in infrared detectors that will eventually lead to effective interstellar spectroscopy in the infrared. Demands for basic molecular data will grow in scope and in level of precision.
Chemical Effects of Interstellar Grains
Authors: Williams David A. 
Published: June 2019

ABSTRACTThe chemical effects of interstellar grains are briefly reviewed. Their dominant chemical role is to catalyze the formation of H2 which is the seminal molecule for efficient gas phase chemistry. In regions of at least moderate extinction grains accumulate molecular mantles of CO, H2O, etc. Solid state chemistry in such mantles may produce molecules of a type or in an abundance not achievable in the interstellar gas. Return of mantle material to the gas can – at least transiently – dominate gas phase chemistry. It is argued that the freeze-out of heavy atomic and molecular species on to grain surfaces limits the time available for chemistry, restricts molecular cloud chemistry to a “young” character, and suggests that chemical models of molecular clouds must have cyclic dynamics. Such models are briefly described.
Wide Field / Planetary Camera-II for the Hubble Space Telescope
Authors: Trauger John 
Published: June 2019

AbstractThe Wide Field / Planetary Camera-II will be available to replace the WF/PC at the first opportunity for in-orbit Shuttle maintenance and refurbishment of the Hubble Space Telescope. It is fundamentally an engineering “clone” of the original radial camera, which nevertheless incorporates a number of science and operational enhancements based on improved technologies. Generic WF/PC performance issues identified and understood early in the WF/PC-II program provide the opportunity for carefully considered, cost effective hardware refinements. The result is improved science performance and operational efficiency for WF/PC-II which will be highly visible to the GO astronomer, and will provide savings in data reduction and calibration overhead.Biased-platinum-gate CCD technology is introduced for the eight imaging sensors, in order to provide long and short term QE stability while obviating the solar UV light channel. Signal chain electronics have been modified in several ways to improve science performance and operational efficiency. The WF/PC set of 48 filters has been reviewed and a number of modifications have been implemented. The WF/PC-II is well into construction at JPL, scheduled for delivery in late 1991.
Voyager: A Retrospective
Authors: Smith Bradford A. 
Published: June 2019

AbstractWithin the brief span of a decade, from 1979 to 1989, the Voyager spacecraft visited the four giant planets – Jupiter, Saturn, Uranus and Neptune – along with their satellites and their rings. The science return from these two spacecraft forever changed our views of this remote region of our solar system. Often overlooked, however, is the incremental gain in knowledge from these encounters over that which had been known in the early 1970s when the Voyager project first came into being. From a post-Voyager perspective, it is astonishing how little was known about the outer planets just a mere two decades ago. Yet, with all of the knowledge that the space program has brought us, there remain a number of unanswered questions and a great many new ones that have been posed as a result of this wealth of new information. Discussed here is summary of the results of the Voyager imaging cameras together with some of the many new questions that subsequently have been raised.
Diffuse Interstellar Clouds
Authors: Lambert David L. , Federman S. R. 
Published: June 2019

AbstractDiffuse clouds are interstellar objects through which starlight is not greatly extinguished. As a result, many studies rely on ultraviolet and visible measurements. The focus of this review is on spectroscopic work involving atomic and molecular lines. From these measurements, the physical and chemical makeup of the clouds is derived. Here we stress that technological advances have influenced our perception of diffuse clouds.
The Interstellar Medium in Nearby Galaxies
Authors: Hulst J. M. Van Der 
Published: June 2019

AbstractRecent observations of the several phases of the interstellar medium in galaxies reveal a wide range of structures and physical properties. The HI structure in nearby galaxies is very filamentary with a large number of shells and filaments suggestive of a close interaction between the star formation in the disk and the surrounding interstellar medium.
Possible Features of IAU Standards
Authors: Seidelmann P. K. 
Published: June 2019

In the past, the IAU has adopted standard values for some constants, primarily for use with solar system ephemerides. The constants adopted in 1976 were specifically adjusted to provide internal consistency. In each case, when constants have been adopted, the changes have reflected accuracy improvements, and the purpose has been to encourage the accomplishment of better science.Over the past 12 years, the Working Group on Cartographic Coordinates has issued triennial reports giving the best values for the sizes and rotations for the planets and satellites. This working group now is an IAU/IAG/COSPAR working group reflecting the different organizations that have recognized the benefits of this group. This is an example of a properly functioning working group, which provides the best values on a regular basis. The IUGG also provides best estimates triennially for values of interest in geodesy and geodynamics.
The Printed Version of the Hipparcos Input Catalogue
Authors: Turon C. , Morin D. , Gomez A. , Crifo F. , Arenou F. , Sellier A. , Marouard M. 
Published: June 2019

AbstractThe data selected for publication and the stellar content of the 118,000 stars constituting the observing programme of the Hipparcos satellite are briefly described.
Double Star Observations with HIPPARCOS: reduction methods and early results by NDAC
Authors: Söderhjelm S. , Evans D.W. , van Leeuwen F. , Lindegren L. 
Published: June 2019

AbstractThe Hipparcos satellite has a predefined observing program given by an Input Catalogue with 118 000 entries. This includes some 10 000 members of known double or multiple systems (with separations above 0.1 arcsec and magnitude-differences below 4-5), which are observably non-single and thus need a more complex reduction procedure. Also, a similar number of hitherto unknown doubles showing deviations from a single-star observation model will be included in the double-star reductions. A key feature in the NDAC reductions is the use of the main reduction results to calibrate and collect the data for individual doubles in ‘Case History Files’. This enables a global solution of both absolute and relative parameters for a double to be carried out later in a single solution. Using provisional data tapes covering small parts of a 14-month interval, tests have been made of major parts of the double star reductions. Comparisons with the main reduction results for single stars indicate that remaining calibration errors are below the 10 milliarcsec level. For known doubles, the solutions are good relative to the Input Catalogue at the expected 0.3 arcsec level, and for a few tens of systems observed with the star-mapper, the agreement is at the 0.05 arcsec level. A few hundred doubles not flagged in the Input Catalogue have also been detected and had their parameters provisionally determined. A detailed paper describing these methods and results has been accepted by Astronomy & Astrophysics.
Blue Stragglers in the Core of the Globular Cluster 47 Tucanae
Authors: Meylan G. , Paresce F. , Shara M. 
Published: June 2019

AbstractHigh resolution imaging observations of the core of the globular cluster 47 Tucanae with the Faint Object Camera (FOC) on the Hubble Space Telescope (HST) reveal a very high surface density of blue stragglers. This discovery supports the hypothesis that they are among the most massive objects in globular clusters, concentrated in the core by mass segregation. Taken together with the presence in 47 Tue of an X-ray source, eleven millisecond and binary pulsars, and two high-velocity stars ejected out of the core, these observations favour the scenario that blue stragglers are either mergers formed through coalescent collisions, or binaries formed through close encounters.
Asteroseismological Probing of the Thermal Evolution of White Dwarf Stars
Authors: Fontaine G. , Wesemael F. 
Published: June 2019

AbstractIt is generally believed that the immediate progenitors of most white dwarfs are nuclei of planetary nebulae, themselves the products of intermediate- and low-mass main sequence evolution. Stars that begin their lifes with masses less than about 7-8 M⊙ (i.e., the vast majority of them) are expected to become white dwarfs. Among those which have already had the time to become white dwarfs since the formation of the Galaxy, a majority have burnt hydrogen and helium in their interiors. Consequently, most of the mass of a typical white dwarf is contained in a core made of the products of helium burning, mostly carbon and oxygen. The exact proportions of C and 0 are unknown because of uncertainties in the nuclear rates of helium burning.
Archiving for Future Extragalactic Image-Databases
Authors: Paturel G. 
Published: June 2019

AbstractOn the experience acquired since 1983 when creating the Lyon-Meudon Extragalactic Database, we discuss the problems of identifying and designating extragalactic objects. We suggest some ways of improvement. The main conclusion is that it is urgent to use images in a standardised format. The IAU could help to organise such a standardisation.
Archiving Asteroid Photometric Data
Authors: Tedesco Edward F. 
Published: June 2019

AbstractCurrent programs which produce asteroid photometric data range from astrometry through visual and near-infrared photometry and spectrophotometry to thermal infrared (8 to 30 micrometers) photometry. These data are published in a variety of places including observatory publications, IAU Circulars, the Minor Planet Circulars, and various journals.
Manterrupting in the German Bundestag: Gendered Opposition to Female Members of Parliament?
Authors: Och Malliga 
Published: June 2019

AbstractThe problem of manterrupting, i.e. men interrupting women to take control of a conversation, claiming superior knowledge, or discrediting women's arguments, has garnered major attention in social and traditional media. Yet scholarly accounts of gendered speech interruption patterns in parliamentary debates are less common. In this article, I argue that manterrupting can be considered a form of resistance against women in politics and, in its worst iteration, prevent female representatives from representing women's interests. This article will analyze the problem of ‘manterrupting’ regarding parliamentary debates in Germany by investigating the nature and extent of male interruptions during parliamentary debates in the 17th legislative period. Drawing on insights from social psychology and masculinity studies, this article finds that in the case of Germany, manterruptions are neither systemic and frequent enough to constitute a form of resistance against women in politics nor do they prevent female representatives from engaging in the substantive representation of women.
The Place of Kastabos in Greek Architecture
Authors: Plommer W. H. 
Published: June 2019

The following article forms the conclusion to my chapter in a projected work on the Temple of Hemithea at Kastabos. The sanctuary is described by Diodorus in Book v, 62—3, and lies about a thousand feet above sea-level on the north-west slopes of the Carian Chersonese, overlooking from the south-east the more easterly isthmus on the long Cnidian Peninsula. It is the first Greek sanctuary of any importance and the first peripteral temple to be explored in the Rhodian Incorporated Peraea (see Fraser and Bean, The Rhodian Peraea and Islands, pp. 123 ff.), of which the whole Chersonese formed part.Our excavation, primarily salvage-work in remote country after a forest-fire had uncovered the remains, formed one stage in the mapping of ancient cities and demes of this neighbourhood by Professor John Cook and Professor George Bean. It established, from a stamped vase-handle and an inscription on a subsidiary building, that this was indeed, as surmised by Cook, the shrine of Hemithea, a local healing-goddess evidently, as Diodorus shows, of considerable local repute. We found that its greatness virtually began in the late fourth century, and was perhaps of fairly short duration.
The Role of the Chorus in Sophocles' Antigone
Authors: Coleman Robert 
Published: June 2019

This essay depends upon certain assumptions, which had better be made explicit at the outset.The first is that in Attic tragedy the choral odes were always intended to have an organic relation to the drama as a whole. They are not mere intermezzi inserted to relieve tension and allow the audience to relax between successive steps in the real business of the drama, but serve rather as lyrical commentaries on what is happening on the stage, inviting us to the emotional response appropriate at that point in the action, and to reflect upon certain ideas and concepts implicit in the events themselves. They form a bridge between successive acts, and their contextual relevance looks back to what has immediately preceded and forward to what is about to come. At this level we need not expect complete consistency between different odes. The Chorus's interpretation of the situation and the emotional reaction it expresses may change quite drastically in the light of a change in situation or the revelation of hitherto unknown facts.
Stesichorus, Fragment 207 P
Authors: Dawe R. D. 
Published: June 2019

Schol. Pind. Ol. x 19, i 315 Dr.κυκνέα μάχη · ὃτι τὸν ἊρɛΞς κύκνΞν Ἡρακλῆς φυγών αὖτις ἀνɛἱλɛ, ΣτησίχΞρΞς ἐν τῶι ɛπιγραφΞμένωι κύκνωι φησίν. 21, p. 316 ɛτράπη μἐν ἐν τῆι μάχηι τΞῦ κύκνΞυ ὁ Ἠρακλῆς. ὁ κύκνΞς υἱὸς ὤν τΞῦ ἌρɛΞς ἐν τῆι παρόδωι τῆς Θɛσσαλίας Ξἰκῶν τΞὺς παριόντας ξένΞυς ἐκαρατόμɛι, έκ τῦν κɛφαλῶν ναὸν τῶι Ἀπόλλωνι (Ἄρɛι coni. Heyne, Boeckh) πΞιῆσαι βΞυλόμɛνΞς. παριόντι τΞίνυν τῶι Ἠρακλɛῖ ἐπɛβΞύλɛυσɛ καὶ σύστάσης μάχης ἐτράπη ɛἰς φυγὴν ὁ Ἡρακλῆς συλλαβΞμένΞυ τΞῦ ἌρɛΞς ὡς παίδι τῶι κύκνωι. ἀλλὰ ὔστɛρΞν αὔτόν μόνΞν γɛνόμɛνΞν ἐνίκησɛν ó ρακλῆς, ita cod. A: fere eadem codd. BCDEQ (ad 19), add. ΣτησίχΞρΞς ɛν τῶι> ἐπιγραφΞμένωι κύκνωι ἱστΞρɛῖ.
Vrbs Avgvrio Avgvsto Condita: Ennius ap. Cic.Diu.I. 107 (=Ann.77–96 V2)
Authors: Jocelyn H. D. 
Published: June 2019

My concern is with the account in Ennius’Annalsof Romulus and Remus and the foundation of Rome, in particular with the verses which Cicero made his brother Quintus quote atDiu.I. 107 (=Ann.77-96 V2)curantes magna cum cura tum cupientes regni dant operam simul auspicio augurioque. ‹… …›†in montef† Remus auspicio se deuouet atque secundam solus auem4 seruat. at Romulus pulcher in alto 80 quaerit Auentino, seruat genus altiuolantum. ‹… … ›certabant urbem Romam Remoramne uocarent. omnibus cura uiris uter esset induperator. †expectant† ueluti, consul cum mittere signum uolt, omnes auidi spectant ad careens oras, 85 quam mox emittat pictis e faucibus currus, sic expectabat populus atque ore timebat rebus, utri magni uictoria sit data regni. interea sol albus recessit in infera noctis. exin candida se radiis dedit ieta foras lux 90 et simul ex alto longe pulcherrima praepes laeua uolauit auis. simul8 aureus exoritur sol, cedunt de caelo ter quattuor corpora saneta auium, praepetibus sese pulchrisque locis dant. conspicit inde sibi data Romulus esse priora, 95 auspicio regni stabilita scamna solumque.
The effects of feeding different starch sources and concentrations on milk production of high yielding Holstein cows
Authors: Lawson R.E. , Moss A.R. , Rymer C. , Blake J.S. 
Published: June 2019

Mansbridge (1995) reported that replacing ground wheat with a mix of ground wheat and maize grain increased milk protein concentration, which led the authors to speculate that increased inclusion of maize grain increased rumen by-pass starch. Indeed, de Visseret al(1990) reported that feeding less rapidly degradable starches has led to increased milk protein concentration.The objective of this study was to examine the effects of starch concentration and source on feed intake, milk yield and milk composition of dairy cows.