bluuebunny/crossref_metadata_2025 huggingface dataset:
Commanding Rape: Sexual Violence, Command Responsibility, and the Prosecution of Superiors by the International Criminal Tribunals for the Former Yugoslavia and Rwanda
Authors: LaViolette Nicole
Published: June 2019

Evidence indicates that individuals responsible for mass rapes in the former Yugoslavia and Rwanda were acting on orders from their superiors. The international criminal tribunals for the former Yugoslavia and for Rwanda have indicated their intention to prosecute individuals responsible for sexual violence and their superiors. The prosecution of superiors rests on the doctrine of command responsibility — a doctrine Well-established in international criminal law. This article presents the difficulties that arise in applying the doctrine of command responsibility to cases of wartime sexual assaults. Relying on a feminist analysis of international humanitarian law, the author identifies the imbalance that exists between the principle of military necessity and the principle of humanitarianism — an imbalance that makes rape the least condemned and punished of war crimes. In the absence of traditional military command structures, as was the case in Bosnia and Rwanda, a superior is well-placed to deny his authority over those who committed wartime rapes. Despite this challenge, the author asserts that the Tribunal for the former Yugoslavia, in theCelebicicase, developed a realistic approach to the doctrine of command responsibility and reasonably concluded that a camp commander was criminally responsible for rapes committed by his subordinates.
Competing Cultures: Canada and the World Trade Organization — The Lessons fromSports Illustrated
Authors: Tawfik Myra J.
Published: June 2019

This article explores the impact of the WTO on Canadian cultural sovereignty. More specifically, it provides an assessment of the recent WTO decision inCanada — Certain Measures Concerning Periodicalsin an effort to demonstrate that the multilateral trade framework is not only incompatible with, but in fact threatens, the continued viability of a distinct Canadian culture.
The Rule of Law and Human Rights in the Balkans
Authors: Green L. C.
Published: June 2019

The author considers the application of relevant human rights provisions to the Balkans both historically and in terms of contemporary issues. In particular, he discusses the legality of the measures taken under the auspices of NATO in respect of Kosovo and queries whether such measures are able to remedy such a breakdown of civil administration and respect for human rights. In the author's view, in such circumstances, administration of a country by the United Nations itself provides the only viable alternative.
La structure constitutionnelle du droit international public
Authors: Kolb Robert
Published: June 2019

Sommaire

Cet article traite du droit international comme un droit de principes (“droit constitutionnel”) bien plus qu’un droit de réglementation détaillée (“droit administratif”). Après un survol de l’origine historique et de la raison d’être de cette caractéristique du droit international, des exemples sont donnés pour illustrer comment le développement de normes autour de grands principes sert parfois les fins de la flexibilité progressive (par exemple à travers le principe du patrimoine commun), parfois en revanche vise à laisser une matière dans l’espace politique, à la discrétion des États (par exemple l’autodétermination). Puis sont abordées les conséquences de cette caractéristique, notamment, la place importante de l’action politique en droit international, la pauvreté normative du droit international, sa codification difficile, la création différée du droit (les principes génèrent la pratique des États), les flottements conceptuels et terminologiques fréquents, l’absence d’une rule of law. Enfin est explorée la tendance récente à préciser le corpus de droit international, à la fois sur le plan normatif et celui des institutions internationales, aptes à formuler en temps et lieu du droit nouveau.
The Aircraft Cases: Canada and Brazil
Authors: Behboodi Rambod
Published: June 2019

The disputes between Canada and Brazil over subsidies to the regional aircraft industry were the first cases under Part II (covering prohibited subsidies) of the Agreement on Subsidies and Countervailing Duties (SCM Agreement) of the World Trade Organization (WTO). The PROEX case, involved the scope of the concept of “special and differential treatment” under Article 27 of the SCM Agreement, and the interpretation of the first paragraph of Item (k) of the Illustrative List of Export Subsidies as set out in Annex I to the SCM Agreement. The Canada — Aircraft case involved, for the first time, Article 1 of the SCM Agreement, which defines what practices constitute a subsidy, and Article 3, which prohibits subsidies “contingent, in law or in fact, upon export performance.” The case also dealt with important procedural issues relating to WTO dispute settlement. The author reviews critically these decisions with respect to both substantive and procedural issues.
A Hesitant Embrace: The Application of International Law by Canadian Courts
Authors: Brunnée Jutta , J. Toope Stephen
Published: June 2019

Canadian courts are approaching the task of mediating the relationship between international law and domestic law with newfound energy. Yet, for all their declared openness to international law, courts are still inclined to avoid deciding cases on the basis of international law. This does not mean that international law is given no effect or that its broad relevance is denied. The avoidance strategy is more subtle: even when they invoke or refer to international law, Canadian courts generally do not give international norms concrete legal effect in individual cases. Although international law is brought to bear on a growing range of questions, its potential impact is tempered — and we fear largely eviscerated — because it is merely one factor in the application and interpretation of domestic law. Within the Canadian legal order the question of “bindingness” of international law is closely intertwined with the manner in which it comes to influence the interpretation of domestic law. In the case of norms that are binding on Canada under international law, Canadian courts have an obligation to interpret domestic law in conformity with the relevant international norms, as far as this is possible. By contrast, norms that do not bind Canada internationally (for example, soft law or provisions of treaties not ratified by Canada) can help inform the interpretation of domestic law and, depending on the norm in question and the case at issue, may even be persuasive. Courts may, and in some cases should, draw upon such norms for interpretative purposes, but they are not strictly speaking required to do so. However, especially following the Supreme Court’s decision inBaker, there appears to be a trend towards treating all of international law, whether custom or treaty, binding on Canada or not, implemented or unimplemented, in the same manner — as relevant and perhaps persuasive, but not as determinative, dare we say obligatory. Our concern is that if international law is merely persuasive, it becomes purely optional, and can be ignored at the discretion of the judge. We argue that it is not enough to treat all normative threads in this fashion — over time this approach risks weakening the fabric of the law.
An Overview of International Fisheries Disputes and the International Tribunal for the Law of the Sea
Authors: McDorman Ted L.
Published: June 2019

Although there have been few international adjudications dealing directly with fishing disputes in the past, all but one of the cases before ITLOS have been fisheries cases. This article first reviews the different ways in which a fisheries dispute can get before ITLOS and considers the disputes that have been on the docket of ITLOS so far. These have resulted in five decisions on requests for prompt release, two decisions on request for provisional measures, but only one decision on the merits of a dispute. The conclusion is that ITLOS has played a useful role in fisheries dispute settlement particularly when contrasted with the history of international dispute settlement for fisheries disputes.
Les actes unilatéraux étatiques en droit international public: Observations sur quelques incertitudes théoriques et pratiques
Authors: Barsalou Olivier
Published: June 2019

Sommaire

En 1997, la Commission du droit international (CDI) entreprenait l’étude des actes unilatéraux étatiques. Phénomène paradoxal, les actes unilatéraux des États traduisent cette ambivalence entre souveraineté et justice qui marque les fondements du droit international public et plus globalement, la société internationale contemporaine. Les travaux du rapporteur spécial Víctor Rodríguez Cedeño n’ont pas échappé à la nature équivoque du droit international. Celle-ci se reflète dans la série de trois critères développés par le rapporteur spécial qui permettent d’identifier un acte unilatéral étatique: l’imputabilité, l’intention et la notoriété. En effet, ces critères, a priori clairs et précis, se révèlent, à la lumière de la pratique internationale contemporaine, insuffisants pour guider le juge international devant lequel est portée une affaire relative à l’interprétation d’un acte unilatéral étatique. Cela crée une situation marquée par l’incertitude et l’imprévisibilité dans les rapports juridiques entre États.
Searching for Accountability: The Draft UN International Convention on the Regulation, Oversight, and Monitoring of Private Military and Security Companies
Authors: Perrin Benjamin
Published: June 2019

The proliferation of private military and security companies has attracted significant public and scholarly attention during the last decade. This comment examines the United Nations Draft International Convention on the Regulation, Oversight and Monitoring of Private Military and Security Companies (Draft Convention). It discusses the significance of the Draft Convention and then describes the approach taken to the regulation of this controversial topic. Several problematic elements of the Draft Convention are identified including the definition of prohibited activities, State responsibility for the conduct of private military and security companies and the proposed International Criminal Court referral mechanism. Finally, specific policy recommendations are made for the government of Canada as a home state and contracting state of private military and security services, irrespective of the progress of negotiations on the Draft Convention.
Canada in the United Nations Treaty Series: A Global Perspective
Authors: Rohn Peter H.
Published: June 2019

How complete is the United Nations Treaty Series (UNTS)? What does an answer to this question mean for our understanding of the law of treaties? If the UNTS is not complete, which treaties are missing? If there are gaps, do they show any patterns? Are some signatories, treaty topics or time periods more gap-prone than others? If we take Canada as a test case, for example, do all post-1945 treaties of Canada actually show up in the UNTS? If there is a gap, can we identify it? If identified, can the gap be explained? How does Canada compare with other countries in UNTS fidelity? Finally, and most importantly, what does the Canadian test case mean for the UNTS as a whole and for the law of treaties?

These questions have come up repeatedly in connection with the UNTS Project at the University of Washington since 1963. There is no comprehensive answer for all of them, but many new details have been found and some patterns have emerged.
The Practice Concerning Treaty Succession in the Commonwealth
Authors: Lawford Hugh J.
Published: June 2019

Although a number of learned articles and even books have appeared recently on the subject of state succession, relatively little has been written about the practical problems faced by a new state seeking to establish the scope of its treaty obligations. An examination of these practical, even mundane, problems indicates that some of the current theoretical arguments are unreal, and that a shift of emphasis in discussion would be desirable.

The practical problems in defining a new state’s treaty obligations are illustrated well by the cases of new Commonwealth countries.

Since mid-1961, a research project at Queen’s University at Kingston, Ontario, has sought to determine which of the old British treaties continue to apply to Canada. Surprisingly enough, even an older Commonwealth country like Canada has not yet been able to reach a firm decision on this question. Thus, Professor (now Dean) Maxwell Cohen of McGill University was obliged to tell the Duke Conference on Canadian-American Treaty Relations in 1961 that existing Canadian publications were inadequate, and to urge that Canada's treaties be collected and published.
Direct Satellite Broadcasting: A Case Study in the Development of the Law of Space Communications
Authors: Gotlieb A. E. , Dalfen C. M.
Published: June 2019

The purpose of this article is to show how legal norms are evolving in an activity newly opened for man by very recent and farreaching technological developments.

The 1963 Radio Regulations of the International Telecommunication Union (ITU) define a “broadcasting satellite service” as “a space service in which signals transmitted or retransmitted by space stations, or transmitted by reflection from objects in orbit around the Earth, are intended for direct reception by the general public.” Direct satellite broadcasting thus refers to the transmission of messages directly to the houses or communities of the general public via artificial space satellites. While such a system does not exist at present, it is expected that it will be feasible within less than a decade.
Newfoundland and the League of Nations
Authors: Gilmore William C.
Published: June 2019

In recent years considerable scholarly interest has been shown in the protracted dispute between the Canadian federal government and its counterpart in Newfoundland and Labrador concerning ownership and jurisdiction over the mineral resources of the continental shelf adjacent and geologically appertaining to the Province of Newfoundland. It is to be expected that the promise of commercial deposits of oil and natural gas indicated during the 1980 drilling season, and the much-publicized discussions between the two governments as to the basis for a possible political solution to the question, will stimulate increased study of the pertinent issues in academic as well as governmental circles.
The Evolution of Canadian Agreements for Co-Operation in Nuclear Weapons and Technology
Authors: Mazer Brian M.
Published: June 2019

The actions of india on May 18, 1974 reinforced the fears of forecasters of horizontal proliferation of nuclear weapons. The Indian detonation of a nuclear device gave tremendous credence to the “Nth” power theory, but more importantly revealed the inadequacy of moral suasion and the need for only peaceful uses of nuclear energy as the basis for nuclear non-proliferation. Since Canada had co-operated with India in the construction of the CIRUS reactor from which the plutonium for the Indian explosion was produced, much attention has been focused upon Canadian actions in co-operation and transfer of nuclear energy technology. The impetus provided by the action of India has produced an insistence by Canada and other nuclear energy suppliers for stricter safeguards to avoid further state action in obtaining nuclear explosive capability.
Des normes régionales et universelles pour les droits de la personne
Authors: Desjardins Alice
Published: June 2019

Les droits de la personne, quelle que soit la forme dans laquelle ils trouvent expression, sont parmi les questions les plus difficiles à traiter. Il importe d’abord de leur donner un sens, en les définissant, et déjà certains d'entre eux, comme le droit à la vie privée, représentent, sous un concept parfois simple, des valeurs multiples et variables d'une groupe social à un autre. Dans d’autres cas, comme dans celui du droit à la vie, les droits expriment une valeur universelle et fondamentale, mais à l’égard desquels les civilisations ont souvent été incapables de donner leur pleine signification.
Individual Radio Pulses from NP 0531
Authors: Sutton J. M. , Staelin D. H. , Price R. M.
Published: June 2019

Observations with a swept frequency machine show that the shapes of individual pulses from NP 0531 are truncated exponentials with widths proportional to λ~4, consistent with the broadening arising from scattering in the interstellar medium. A histogram of pulse intensity reveals two different populations. The very strong pulses are associated only with the main pulse and interpulse.
Timing Observations of the Crab Nebula Pulsar at the Arecibo Observatory
Authors: Roberts J. A. , Richards D. W.
Published: June 2019

Timing observations of the Crab pulsar were made between 10 May 1969 to 3 July 1970. Arrival times were corrected to the barycentre of the solar system; a further correction was made for the effect of dispersion. The only jump in period occurred in September 1969, although small irregularities in the period occurred at other times. A third order polynomial fitted all the observed data to within ±0.15 pulse periods.
Timing of the Pulsar NP 0527
Authors: Richards D. W. , Roberts J. A.
Published: June 2019

Timing measurements have been made of NP 0527 in order to examine its physical relationship with NP 0532. 18 months of timing data have been used to obtain an accurate frequency, rate of change of frequency and position. The calculated ‘slowdown age’ of the NP 0527 is 3.0 × 106years which rules out an origin in the supernova explosion of 1054 A.D. The upper limit of its transverse velocity is 0.046c which is significantly less than the value necessary if it had a common origin with NP 0532.
The Non-Thermal Continuum from the Crab Nebula: The ‘Synchro-Compton’ Interpretation
Authors: Rees M. J.
Published: June 2019

The continuum emission from the Crab Nebula may be radiation from relativistic electrons moving in the electromagnetic wave field radiated by the rotating magnetic dipole of the pulsar. This radiation, called Synchro-Compton radiation, would show ordering over the whole nebula, as is observed in measurements of polarisation. The properties of this radiation are described in an Appendix.
Radiation from Pulsars
Authors: Lerche I.
Published: June 2019

We suggest that an oscillating interface, carrying a steady current between a rotating, radiating, magnetic dipole and an external plasma is the source of pulsar radiation produced over a broad band of high frequencies (108–1018 Hz). The efficiency of the radiation mechanism is so high that the oscillation energy goes mainly into radiation in each cycle of the oscillation.
High-Resolution Studies of Neutral Hydrogen in NGC 5383 and M101
Authors: Allen R. J. , Goss W. M. , Sancisi R. , Sullivan W. T. , Van Woerden H.
Published: June 2019

Maps with 0′.5 resolution are presented of the distribution of neutral hydrogen in two galaxies. The barred spiral NGC 5383 contains much hydrogen, in strong differential rotation, in its outer parts; some H I concentrations with possibly anomalous velocities are observed in the regions of bar and nucleus. In the giant Scd spiral M101, the H I distribution corresponds closely with the optical spiral pattern, except for a lack of hydrogen in the central region.
Fundamental problems and basic tests of stellar evolution theory — The case of carbon stars
Authors: Iben Icko
Published: June 2019

Carbon stars are thought to be in the asymptotic giant branch (AGB) phase of evolution, alternately burning hydrogen and helium in shells above an electron-degenerate carbon-oxygen (CO) core. The excess of carbon relative to oxygen at the surfaces of these stars is thought to be due to convective dredge-up which occurs following a thermal pulse. During a thermal pulse, carbon and neutron-rich isotopes are made in a convective helium-burning zone. In model stars of large CO core mass, the source of neutrons for producing the neutron-rich isotopes is the 22Ne(α, n)25Mg reaction and the isotopes are produced in the solar system s-process distribution. In models of small core mass, the 13C(α, n) 16O reaction is thought to be responsible for the release of neutrons, and the resultant distribution of neutron-rich isotopes is expected to vary considerably from one star to the next, with the distribution in isolated instances possibly resembling the solar system distribution of r-process isotopes. After the dredge-up phase following each pulse, the 13C is made by the reactions 12C(p,γ) 13N(β+ v) 13C in a zone of large 12C abundance and small 1H abundance that has been established by semiconvective mixing during the dredge-up phase. There is qualitative accord between the properties of carbon stars in the Magellanic Clouds and properties of model stars, but considerably more theoretical work is required before a quantitative match is achieved.

The observed paucity of AGB stars more luminous than MBOL ∼ −6 is interpreted to mean that the AGB lifetime of a star more luminous than this is at least a factor of ten smaller than the AGB lifetime of stars less luminous than this, or, at most 105 yr. Since, with current estimates of the 22Ne(α, n)25Mg reaction rate R22, only AGB model stars more luminous than MBOL ∼ −6 can produce s-process isotopes in the solar system distribution, it is inferred that either (1) the current estimates of R22 are too small by one to two orders of magnitude, allowing less luminous AGB stars to contribute, (2) the solar system distribution is not equivalent to the average Galactic distribution, being rather the consequence of a unique injection into the protosolar nebula of matter from a massive intermediate-mass AGB star, or (3) the estimates of the temperatures in the convective shell that are given by extant models are too low by, sav, 10 or 15 percent.

The absence of carbon stars more luminous than MBOL ∼ −6 is suggested to be due primarily to the fact that ∼ 106 yr of AGB evolution is necessary to produce surface C/O > 1, rather than to be due to the burning of dredged-up carbon into nitrogen at the base of the convective envelope during the interpulse quiescent hydrogen-burning phase. Thus, the positive correlation between the nitrogen and helium abundances in planetary nebulae is perhaps primarily a consequence of the second dredge-up episode rather than a consequence of processes occurring during the thermally pulsing phase.
Two nonstandard solar models: With mixed interiors and with enhanced heavy element opacity
Authors: Pamyatnykh A. A. , Sapsaj I. K.
Published: June 2019

We present and briefly discuss basic characteristics of a standard solar model as well as those for two series of nonstandard models computed with Paczyński's stellar evolution code.
Constraints on stellar evolution by observation of white dwarfs
Authors: Weidemann V.
Published: June 2019

The recent observation of white dwarfs in the open cluster NGC 2516 and the determination of their surface gravity and effective temperatures (Reimers and Koester, 1982) has enabled the establishment of the initial-final mass relation for low and intermediate mass stars which was published a few months ago and is presented here (Fig. 1 of Weidemann and Koester, 1983a). The most important conclusions drawn are:

1.

The limiting mass for white dwarf progenitors is 8–9 M⊙ rather than 5–6 M⊙, with supernova production beyond;

2.

The rather flat run of the initial-final mass relation in the main range of star production, 1–5 M⊙, explains the observed narrow mass distribution of white dwarfs and central stars of planetary nebulae around 0.6 M⊙;

3.

High mass white dwarfs exist, as shown in the rich, young cluster NGC 2516, but are extremely rare in general.
Tidal effects in close binary stars
Authors: Zahn Jean-Paul
Published: June 2019

This review addresses the question of what can be learned about the stellar interiors from the study of the tidal effects in close binary stars.
Cepheid period changes and stellar evolution
Authors: Fernie J.D.
Published: June 2019

The question of whether or not the period changes observed in some classical cepheids are due to evolution across the HR diagram remains controversial. On the one hand, it is known that the stars are indeed evolving across the diagram and are therefore changing their radii and must therefore be changing their periods. On the other hand, only a fraction of cepheids appear to have period changes, and some of these seem to be in the form of sudden jumps. Is it then that the evolutionary changes are too small to be detected, and the observed changes due to something else? This note explores the question.
Some Difficulties in the Theory of Nutation
Authors: Jeffreys Harold
Published: June 2019

Fedorov (1958) made a splendid discussion of data on the nutations; Vicente and I made a theory, taking account of a fluid core and of an elastic shell. The agreement was far better than had been found before, but some inconsistencies remained.
Nutation and the Oppolzer's Terms
Authors: Fedorov E. P.
Published: June 2019

Two fundamental frames of reference are used in the study of the rotation of the Earth: the nonrotating celestial coordinate system XYZ attached to the directions to stars and/or extragalactic sources, and the terrestrial coordinate system xyz attached in “a prescribed way” to several points (observatories) on the surface of the Earth or to the pencil of unit vectors drawn from an arbitrary origin parallel to the local verticals at these points.
Nearly Diurnal Free Polar Motion Derived from Astronomical Latitude and Time Observations
Authors: Yatskiv Ya. S.
Published: June 2019

The first attempts to take into account the dynamic effect of a liquid core on the rotation of the Earth were made as far back as the end of the 19th century.
The Earth's Constitution and the Nutations
Authors: Vicente R. O.
Published: June 2019

The theoretical researches on this subject were first developed in a consistent theory, in 1765, by Euler, who studied the theory of the motion of a rotating rigid body. Bradley shortly before, in 1737, had discovered the first forced nutation, with a period of 18.6 years, which was explained by d'Alembert.
On the Nature of the Nonhydrostatic Quadrupole Excess Moment of the Earth
Authors: Ruzmaikina T. V.
Published: June 2019

I wish to discuss an effect that is caused by the secular decrease in the Earth's rotation. I shall show that this deceleration induces mass flows across level surfaces and that these flows redistribute temperature and density in the Earth and produce an excess equatorial bulge. This mechanism does not require large lower mantle viscosity, unlike mechanisms discussed by Munk and MacDonald (1960) and McKenzie (1966). Therefore it does not suffer from the difficulties pointed out by Goldreich and Toomre (1969).
Rotation Curve and Mass Model for the Edge-On Galaxy NGC 5907
Authors: Casertano S.
Published: June 2019

The rotation curve of the edge-on disk galaxy NGC 5907 can be interpreted in terms of a two-component model, consisting of a truncated exponential disk and of a spherical halo. About 60% of the total mass inside the edge of the disk turns out to be in the halo. Indicative masses for disk and halo are 9 and 13.5·1010 solar masses respectively.
Fourier Analysis of Spiral Tracers. A Progress Report
Authors: Considère S. , Athanassoula E.
Published: June 2019

Fourier analysis of the observed distribution of spiral tracers (e.g. HII regions) can yield a wealth of information about the spiral structure of a given galaxy. A description of the method has been given by Kalnajs (1975) and, in brief, involves decomposing the observed distribution into components with given angular periodicity m. Component m = 0 corresponds to the axisymmetric part, m = 1 to either a one-armed spiral or an asymmetry, m = 2 to a spiral or a bar, etc. Each component is then analysed into a superposition of logarithmic spirals. This does not imply that the observed spirals are assumed to be logarithmic, but rather that logarithmic spirals are convenient building blocks.
Periodic Orbits and Warps
Authors: Mulder W. A.
Published: June 2019

Orbit calculations were done in a rotating triaxial system with a density distribution in accordance with recent observations of spiral galaxies. A search was made for simple closed orbits which are tilted with respect to the plane of the galaxy. A family of stable prograde tilted orbits was found which can explain warps as stationary phenomena.
Instabilities of Hot Stellar Discs
Authors: Athanassoula E. , Sellwood J. A.
Published: June 2019

We use computer simulations to determine the dominant unstable modes of stellar discs having the surface density distribution of Toomre's (1963) model 1 and large random motions in the plane. Particles in the models have their initial coordinates chosen from distribution functions to ensure that the configurations would, in the limit of infinitely many particles, be stationary solutions of the Vlasov and Poisson equations. The 40,000 particles in our simulations are constrained to move on a plane and we use a polar grid based Fourier method to determine the force field (Sellwood 1982). The surface density is smoothly tapered to zero at six scale lengths and the softening length is 1/30th of the outer radius of the disc.
Stabilizing a Cold Disk with a 1/r Force Law
Authors: Tohline Joel E.
Published: June 2019

Massive “dark” halos are currently believed to surround individual galaxies and systems of galaxies primarily because: (a) individual galaxies exhibit “flat” rather than Keplerian rotation curves (see the review by Faber and Gallagher 1979); (b) the measured ratio of mass to light in systems of galaxies continues to increase roughly linearly with radius as one observes larger and larger systems (Rood 1982); and (c) rapidly spinning “cold” stellar disks are not dynamically stable if they are fully self-gravitating (Ostriker and Peebles 1973). It can be shown, however, that properties (a) and (b) of galaxies and systems of galaxies can be explained without invoking dark halos if one assumes that the force of gravity has the form
where r is the distance between the attracting bodies of masses M and m, and the scale “a” must assume a value a ∼ 1 kpc. (See Milgrom 1982 and Bekenstein, these proceedings, for a discussion along similar lines.) Newton's Law is retrieved on scales « a but the force is proportional to 1/r on scales » a. Equation (1) should not be adopted in place of Newtonian gravity to explain the dynamical properties of galaxies unless it also explains property (c) without invoking the presence of dark halos.
Periodic Orbits and Gas Flow in Barred Spiral Galaxies
Authors: Sanders R. H. , Teuben P. J. , van Albada G. D.
Published: June 2019

One purpose for studying the gas flow in barred spiral galaxies is to use the observed distribution and kinematics of the gas as a tracer of the underlying gravitational field. By comparing model hydrodynamical calculations with observations of actual systems, one would like to define three basic properties of barred galaxies:

1)

The bar strength. How significant is the deviation from axial symmetry in the region of the bar, measured by some parameter such as qt, maximum aximuthal force in terms of the mean radial force (Sanders and Tubbs, 1980).

2)

The mean radial distribution of matter. Clearly in a system with large deviations from circular motion, the “rotation curve” gives no direct information on the radial mass distribution.

3)

The angular velocity of the bar. Where is the co-rotation radius (or Lagrange points) with respect to the bar axes? Are other principal resonances present?
Kinematics of the Barred Galaxy NGC 1365
Authors: Jörsäter Steven , Lindblad Per Olof , Peterson Charles J.
Published: June 2019

NGC 1365 is a galaxy which has lately received a lot of attention from people studying the structure and dynamics of barred galaxies. This is not surprising since it is one of the best suited objects in the sky. We have obtained a number of long-slit spectra in the red region (Hα, [NII], [SII]) with the ESO 3.6 m (Lindblad and Jörsäter) and with the CTIO 4 m (Peterson) telescopes. In addition, a couple of Fabry-Perot Hα interferograms have kindly been given to us by G. Comte and Y. Georgelin. Some preliminary results are presented here. Fig. 1 shows the positions of measured velocity points. The digits along the vertical axis indicate distance from the nucleus in seconds of arc. The dashed line at P.A. 48 deg indicates the line of nodes as determined from photometry of the outer features of the galaxy (Lindblad 1978). An arbitrary isophote has been sketched to aid the orientation. The emission lines in the bar are surprisingly weak which is the reason for the scarcity of velocity points there. Fig. 2 shows a rotation curve based on the P.A. of the line of nodes of 48 deg and an inclination of 55 deg (Lindblad 1978). Only velocity measurements within 50 deg of the line of nodes have been used in this diagram in order to avoid large projection errors. The distance used is 20 Mpc. The spread is quite large indicating a significant amount of non-circular motion.
Gas and Star Kinematics in Elliptical Galaxies
Authors: Bertola F. , Bettoni D. , Capaccioli M.
Published: June 2019

Since the time it became evident that ellipticals are not rotationally supported, there has been an increasing interest on their dynamical properties, and new models have been formulated. However, the spectroscopic, as well as the photometric and morphological observations, do not provide yet a clear understanding of the structure of these objects, just proving that they are much more complicated than thought before. An obvious way to attack the problem seems to look at the motions of the gaseous component in those few cases where it is present, because of the different response to the same potential field of the gas and star components.
Optical Kinematics of Strong Radio Galaxies
Authors: Simkin S. M.
Published: June 2019

Recent spectroscopic measurements of 5 strong radio galaxies showed that approximately 50% of these objects had internal gas velocities which were notably non-circular. To investigate this, more detailed observations were done for the galaxies in question. Examination of these results suggests that the non-circular velocities tend to fall into a pattern. All of the objects have one kinematical component which fits the classical picture of “circular rotation”. This occurs in BOTH the stellar and ionized gas and displays MUCH HIGHER peak velocities than are found in E galaxies. In addition, all of the objects studied possess a second ionized gas system at a different velocity from that of the rotating gas. Finally, at least one of the objects has an envelope of stars which is either not rotating or has a very different kinematic major axis from that of the stellar population in its inner regions.
SO and Smooth-arm Sa's within the Hubble Sequence
Authors: Sandage Allan
Published: June 2019

SO and smooth-armed Sa galaxies are generic to the Hubble sequence, not formed by environmental stripping.
The Interaction of Supernova Ejecta with an Ambient Medium
Authors: Chevalier Roger A.
Published: June 2019

Plausible environments for supernovae are the interstellar medium with constant density or a circumstellar medium built up by mass loss with ρ ∝ r−n Self-similar solutions for the interaction region between the expanding supernova gas and the ambient gas exist provided that the expanding gas has ρ ∝ r−n with n > 5. The circumstellar medium case is likely to be important for the early evolution of Type II supernovae because their progenitor stars are probably red supergiants. The radio and X-ray emission observed from extragalactic supernovae may be from this interaction region. The early self-similar solutions can also be applied to the young galactic remnants.
Near Infrared Spectroscopy of Galactic and Magellanic Clouds Supernova Remnants
Authors: Dennefeld M.
Published: June 2019

The spectral range redwards of about 7300 Angströms has up to now been rarely explored for any kind of object because of lack of adequate detectors. This situation is changing with the availability of silicon detectors whose response extends up to 1.1μ with reasonable quantum efficiency. We have used the ESO Reticon System behind the Boller and Chivens Spectrograph at the Cassegrain focus of the ESO 3.6m telescope to obtain spectra of several Supernova Remnants in the range 6000–10500 Å. The spectral resolution was 8 å and the dual array allowed a clear sky-subtraction, indispensable because of the presence of numerous atmospheric OH bands in this region. Data reduction was done with standard techniques using wavelength calibration, flat-field correction, response curve determination through observations of standard stars and extinction correction. We present below results based on the first spectra obtained for the Galactic remnants RCW 86, RCW 103 and Kepler SNR and the Magellanic Cloud ones N 49 and N 63A. The Crab Nebula will be discussed separately at the end.
The W28 Supernova and the Surrounding Interstellar Medium
Authors: Zealey W. J. , MacGillivray H. T. , Malin D. , Hartl H.
Published: June 2019

A large shell, 1.5 degrees in diameter, outlined by nebulosity and dust clouds has been found centred on the W28 supernova remnant. Obscuration has been studied over a 2 degree square area centred on W28. The W28 SNR is coincident with a region of reduced obscuration. The densest parts of the obscuration AB≥ 4m is coincident with the molecular clouds associated with M20 and the OH maser to the south of M20.

The observed absorption is interpreted as being the result of the expansion of the W28 SNR into an older pre-existing SNR or stellar wind bubble.
Heating of the Interstellar Medium by Supernova Remnants
Authors: Cox Donald P.
Published: June 2019

We observe the heating of interstellar material in young supernova remnants (SNR). In addition, when analyzing the soft X-ray background we find evidence for large isolated regions of apparently hot, low density material. These, we infer, may have been heated by supernovae. One such region seems to surround the Sun. This has been modeled as a supernova remnant viewed from within. The most reasonable parameters are ambient density no ~ 0.004 cm−3, radius of about 100 pc, age just over 105 years (Cox and Anderson 1982).
The X-Ray Emission of a Clumpy Irregular Galaxy from Thousands of Supernova Remnants?
Authors: Heeschen D. S. , Heidmann J.
Published: June 2019

Clumpy irregular galaxies contain 5–10 “clumps” which are hyperactive HII complexes each equivalent to 100 giant HII regions of the 30 Doradus type (Heidmann 1982). We observed one of them, Mkn 325 (= NGC 7673), with the Einstein IPC in Dec. 1980 (seq.no 10201) for 3,200 s. The reduction was made kindly by D.E. Harris. The source was localized at 23h 25m 12.2s, + 23° 18′ 25″ (1950) in agreement with the optical position, at a quite weak level (14 counts in the 1.4–2.9 kev range). Thus we could not get valuable spectral information, only that the spectrum is rather not soft. Correction for galactic absorption NH = 5 ×1020 at.cm−2 (Heyles 1975) is applied. Fits of power law spectra happen to all go through the point with flux density 4.5 ×10−5 mJy at 3.0 ×1017 Hz (1.24 kev) and they yield a flux (1.1 ± 0.3) x10−13 erg cm−2 s−1 inside 1–3 kev and an X-luminosity (2.2 ± 0.3)×1041 erg s−1 inside 0.5–4.5 kev, for a distance 49 Mpc.
Radio-Source Evolution and the Redshift Cut-Off
Authors: Peacock J. A.
Published: June 2019

The idea that there may be a cut-off in the distribution of quasars at high redshifts (z∼4) has been of some recent interest through the work of Osmer (1982). The observation of such an epoch of quasar creation is potentially of great importance in relation to theories of galaxy formation, but the evidence from optically-selected quasar samples remains uncertain: quite apart from the notorious problems in achieving quantifiable completeness in objective-prism surveys, any observed lack of high-redshift quasars may always be attributed to absorption either by a neutral IGM or by dust in intervening galaxies. Radio-selected samples, however, do not suffer from these problems, and this paper aims to review what studies of extragalactic radio sources can tell us about the numbers of objects at the highest redshifts.
Deep Radio Source Counts and Small Scale Fluctuations of the Microwave Background Radiation
Authors: Danese L. , de Zotti G. , Mandolesi N.
Published: June 2019

Source counts which now extend to surface densities of ∼105 sources/sr make possible a direct evaluation of the radio source contribution to the small-scale fluctuations in the microwave background on scales larger than ∼10′, at wavelengths cm. Comprehensive radio spectral data permit a straightforward and largely model-independent extrapolation of the N(S) relation to shorter wavelengths. On the other hand, Peacock and Gull (1981, hereafter PG) have constructed a set of models which incorporate a wealth of additional data, such as local luminosity functions, luminosity/redshift distributions, luminosity-spectral index correlations; they can therefore be exploited to optimize the extrapolations both to higher frequencies and to fainter flux densities. Only one of these models, however, namely No. 4, is consistent with the recent P(D) results (Wall et al. 1982; Ledden et al. 1980) which provide information on the areal density of sources at s~1mJy; therefore, in the following we shall focus on it.
The Center for Astrophysics Redshift Survey
Authors: Davis M. , Huchra J. , Latham D.
Published: June 2019

We have completed the survey of radial velocities for all 2400 galaxies brighter than 14.5 at high galactic latitude in the northern hemisphere. This data set has already been used to derive a good measure of the local mean mass density, describe the overdensity and the dynamics of the local supercluster and to analyse the dynamics of groups and clusters of galaxies within the sample volume.
A Photometric and Morphological Investigation of Very Remote Clusters
Authors: Kruszewski A. , West R. M.
Published: June 2019

About 500 remote, mainly compact clusters of galaxies have been identified on ESO (R) Schmidt plates; around 40 of these have been observed with the ESO CCD camera on the Danish 1.5-m telescope on La Silla. We describe the method of identifying the clusters and give some preliminary photometric results.
Supernovae as a Cosmological Tool
Authors: Trimble Virginia
Published: June 2019

Cosmology can mean many different things to different people. Sandage (1970) once described it as “the search for two numbers” (Ho and qo). At the other end of the spectrum, it may comprise almost all the interesting bits of astronomy and physics that bear on how the universe got to be the way it is. Supernovae can probe many of these bits because they are bright, have been going on for a long time, and contribute directly to the chemical and, perhaps, dynamical evolution of structure in the universe.
The Ursa Major Supercluster
Authors: Schuch N. J.
Published: June 2019

The Ursa Major supercluster is an association of ten Abell clusters which lie within 7° of each other. The center of the system has equatorial coordinates RA (1950.0) and galactic coordinates l = 143°, b = 60°.
The Indus Supercluster
Authors: Corwin Harold G.
Published: June 2019

A survey of rich galaxy clusters, redshifts for many of those clusters, and galaxy counts by eye to B = 19.0 show the Indus Supercluster to be an annular (in projection) configuration of nine rich clusters at 0.073 < z < 0.080 apparently connected by bridges of galaxies.
The Southwest Extension of the Perseus Supercluster
Authors: Focardi P. , Marano B. , Vettolani G.
Published: June 2019

The main structure of the Perseus supercluster is defined by a long chain of clusters and rich groups of galaxies with very similar radial velocities The redshift survey performed by Gregory et al. (1981) has shown that most of the “field” galaxies are also members of the supercluster.
Evolutionary Effect in Quasars as a Consequence of Galaxy Formation Process
Authors: Shklovsky I. S.
Published: June 2019

Many years ago M. Schmidt established the presence of a strong evolutionary effect in quasistellar objects (QSOs). Though this important problem is not yet fully resolved, there can be no doubt that in earlier epochs of the Universe evolution of the spatial density of QSOs (in the comoving coordinates) was much higher than it is now. Thus, for instance, the spatial density of the optically selected QSO is:

according to Schmidt (1977). Here τ = z/(l+z), whence, for instance, if z = 3, ρ ∼ 1000 ρ0, where ρ0 is the local density.
Can all Quasars be Gravitationally Lensed SY's Nuclei?
Authors: Setti G. , Zamorani G.
Published: June 2019

There has been a good deal of discussion in recent literature about the hypothesis, first put forward by Barnothy and Barnothy (1968), that quasars could be gravitationally lensed nuclei of Seyfert's galaxies (Turner, 1980; Tyson, 1981). Large amplifications (> 3–4 magnitudes) are needed to account for the widespread distribution in the intrinsic optical luminosities of quasars. A direct verification of this hypothesis is difficult to achieve due to the limited angular resolution of ground based telescopes. However, this hypothesis may be tested in a global sense by referring to radiation properties of Sy 1 nuclei which must be preserved, or must change in any predictable way, through the lensing process.
Statistical Analysis of Optically Variable QSOs and Bright Galaxies: A Hint for Gravitational Lenses?
Authors: Bacon R. , Nieto J.-L.
Published: June 2019

Nieto (1979) found an excess of optically variable QSOs (OV) near bright galaxies (m < 15.7): 6 observed versus 1.6 expected for r < 5′. The probability involved was p = 5 × 10−3. Because of the small number of OV QSOs in this sample (N = 41, sample 1), this result needed a confirmation. So the same analysis was repeated with a sample of 112 QSOs (sample 3) from Hewitt and Burbidge (1980). Eleven objects were observed at r < 5′ versus 4.4 expected, so p = 4 × 10−3, the sample made up with 71 objects (sample 2) supporting slightly the result found with the first 41 objects. A notable difference between these two samples 1 and 2 is that the objects included in sample 2 are fainter than the objects included in sample 1. Repeating then the same analysis on samples of QSOs at different brightness levels suggests that the excess is related to the apparent brightness of the QSOs.
The LMC Globular Cluster Hodge 11 (=SL 868)
Authors: Stryker L. L. , Nemec J. M. , Hesser J. E. , McClure R.D.
Published: June 2019

The age of the star cluster H11 has been controversial for a number of years. The color-magnitude diagram (CMD) of Walker (1979) to V=21.5 was interpreted as an “…evolved main-sequence, whose termination point corresponds to an age of about 0.6 Gyr, but with a giant branch which is displaced blueward by about Δ (B-V)o=0.4 from the positions of the giant branches of open clusters of similar age in our Galaxy.” On the other hand, the integrated colors are similar to those of metal-poor globular clusters in the Galaxy (Freeman and Gascoigne 1977, and references therein), and “…incompatible with an age of say 0.3 Gyr.” Searle, Wilkinson and Bagnuolo (1980) classify it as Group VII, the oldest group. The system has no RR Lyrae stars (Graham and Nemec 1984).
Far-UV Photometry of Magellanic Cloud Globular Clusters
Authors: de Boer Klaas S.
Published: June 2019

The International Ultraviolet Explorer (IUE) has been used by me since January 1979 to observe globular clusters in the LMC, under various IUE programs in collaboration with Art Code. A first report was presented at the NASA 2nd IUE conference in 1980 (de Boer 1981a). A comparison of the UV colors for 11 MC clusters with the colors of galactic globular clusters was presented during IAU Colloquium 68 (de Boer 1981b), in a review which accumulates also all references to literature on far-UV photometry of galactic globular clusters. Using the VILSPA data base Cacciari et al (1982) repeated the comparison. The spectra of three clusters with good signal were presented by Code (1982). Data for a few other clusters were reported by Cacciari and Fusi-Pecci (1981) and by Cassatella and Geyer (1982; and this symposium).