bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Search for 43.122 GHz SiO Emission from Symbiotic Stars
Authors: Hall P. J. , Wark Robin M. , Wright Alan E. 
Published: July 2016

AbstractDuring the second half of 1986 tests were made of a new Q-band (43 GHz) receiver designed for the Parkes radio telescope. As part of the trial observation program 12 symbiotic stars were examined for SiO maser emission. No significant new emission was detected from any of the candidates, although several previously known SiO sources (including one symbiotic star) were confirmed. We conclude that potential SiO maser action near the Mira star in most symbiotic systems is prevented by the presence of the hot companion star.
2.3 metre multi-colour photometry of a new AM Herculis variable
Authors: Tuohy I. R. , Ferrario L. , Wickramasinghe D. T. , Hawkins M. R. S. 
Published: July 2016

AbstractWe present UBVRI photometry of the faint and highly erratic cataclysmic variable discovered by Hawkins (1983) from a sequence of U.K. Schmidt plates. Observations using the ANU 2.3 m telescope over two nights in September 1986 show pronounced and repeatable modulation at a binary period of 108.6 min. Dramatic colour differences are evident in the folded UBVRI light curves: in the U band, a single sinusoidal peak is present, while at longer wavelengths, a second red peak dominates at a phase separation of Δϕ = 0.5. This behaviour is strongly suggestive of cyclotron emission from two magnetic accretion funnels in an AM Herculis binary system. Furthermore, the binary period lies in the narrow range of 100-115 minutes that characterizes most of the AM Herculis variables lying on the short side of the 2-3 hour period gap. We conclude therefore that the object is almost certainly a new AM Herculis system, and develop a model in which the blue and red components originate from two non-diametrically opposed cyclotron regions that are characterized by differing electron temperatures and opacities. Predictions are made regarding the linear and circular polarization properties of this important new magnetic variable.
The Lyman Far Ultraviolet Spectroscopic Mission (Invited Paper)
Authors: Tuohy Ian R. , Dopita Michael A. 
Published: July 2016

AbstractThe Lyman mission will undertake the first sensitive high resolution spectroscopic observations in the largely unexplored 912-1216Å region. This astrophysically critical wavelength interval is exceedingly rich in diagnostic spectral lines such as the Lyman series of atomic hydrogen and deuterium, the Lyman and Werner bands of molecular hydrogen and deuterium, and the resonance lines of numerous important species including CIII, NI-III and OVI. Lyman will have a major impact in all areas of modern astrophysics, with the most fundamental contribution being the determination of light element abundances in the local interstellar medium and in the intergalactic medium at low redshift. The mapping of hot gas (T ∼ 3 × 105K) and molecular hydrogen and HD in the disk and halo of our galaxy represent additional major objectives for which Lyman is uniquely qualified.The Lyman payload will comprise a grazing incidence telescope and three spectroscopic instruments: the prime spectrograph operating between 912-1250Å with a resolution of λ/ Δλ ∼ 30,000, a far ultraviolet spectrograph (1200-2000Å;λ/ Δλ ∼ 10,000), and an extreme ultraviolet spectrograph (100-900Å; λ /Δλ ∼ 300). Observations will be conducted from a highly efficient 48 hour elliptical orbit which will allow long un-interrupted exposures and real time operations. It is anticipated that Lyman will be launched by Ariane in 1996, and will have an operational lifetime of at least 5 years. Data reception and spacecraft control will be undertaken from ground stations in Spain and in Australia.Lyman is currently being studied at Phase-A level by Australia in close coordination with the European Space Agency. The scientific involvement is the responsibility of the Lyman Science Working Group, composed of members representing the various astronomical institutions in Australia. Funding to support the technical and scientific aspects of the mission is provided via the Australian Space Board and the Department of Industry, Technology and Commerce in recognition of the major opportunity that Lyman presents to the Australian aerospace industry.
Ultraviolet Observations of SN 1987A
Authors: Panagia N. 
Published: July 2016

AbstractThe IUE observations of SN 1987A are presented and the most important results are briefly summarised. The photometric observations of SN 1987A are discussed in some detail in the context of the supernova energetics. Adding the information from spectroscopy and neutrino observations, it is concluded that SN 1987A is a ‘normal’ Type II explosion (i.e. core collapse of a massive star) with an unusually compact initial configuration, just as expected for the progenitor Sk −69°202.
SN 1987A in the UV: the Progenitor Star, the Reddening and the Possible Detection of a UV Light Echo
Authors: Gilmozzi Roberto 
Published: July 2016

AbstractSome special issues to which IUE observations have provided crucial insight are presented. The arguments leading to the definitive identification of Sk−69°202 as the progenitor of the LMC supernova are reviewed, and a preliminary determination of the reddening toward SN 1987A, based on the IUE spectra of stars 2 and 3, is discussed. Recent observations at the predicted position of the SN ultraviolet light echo are reported, and evidence, albeit circumstantial, is provided that a UV echo has been detected. Some consequences of this result are explored. The relevance of this observation lies in the fact that a UV echo, if really detected, would give direct information of the spectrum of the SN at the time of the shock breakout.
Absolute Spectrophotometry of SN 1987A and the Hα Bochum Event
Authors: Hanuschik Reinhard W. 
Published: July 2016

AbstractSpectrophotometric optical fluxes of SN 1987A have been measured at high accuracy with the 61cm telescope equipped with a rapid spectrum scanner. This highly homogeneous data set covers the wavelength range 3200-8700Å at 10Å resolution. Selected wavelength regions, e.g. around Hα, have also been measured at 3Å resolution. The Hα line shows an undisturbed P Cygni-type profile until March 15, superimposed by variable fine-structure thereafter, developing within a few days into a blue-shifted, peak-like flux excess and a red-shifted flux deficiency. This fine-structure is intrinsic to Hα. Similar fine-structure is also observed in Na I-D, in Paschen-α and possibly in Hβ. We discuss our observations in terms of the ‘mystery spot’, and of models involving a jet and interactions with surrounding pre-existing material, and we propose density inhomogeneities, or occupation number deficits due to NLTE effects, within the inner regions of the envelope as origin.
Review of Speckle Observations of Supernova 1987A
Authors: Meikle W.P.S. 
Published: July 2016

AbstractSN 1987A is sufficiently close to allow a unique examination of the morphology of a supernova, using speckle interferometry. Several groups [Center for Astrophysics (CfA); Imperial College (IC); Mount Stromlo and Siding Spring Observatories/Anglo-Australian Observatory (M/A)] have reported optical speckle observations. At Hα, both CfA and M/A have determined the angular extent of the emission, and reasonable agreement is obtained. The speckle-derived values are consistent with those obtained from line profiles. IC has also succeeded in resolving the supernova at Hα. At wavelengths other than Hα, at early epochs, angular diameters obtained by CfA are larger than those derived from photometric and spectroscopic measurements, possibly due to scattering effects. At later epochs, the diameters exhibit little variation between the wavelengths examined. CfA reports significant asymmetry in the late epoch data.Several attempts have been made to re-observe (at optical wavelengths) the companion object, but none have succeeded. The nature of this phenomenon is still controversial, but the evidence indicates that the companion was real, with emission from dust apparently being the least problematic explanation. Support for this may lie in IR speckle observations (Haute Provence/Lyon) which, on about day 115, indicated the presence of one or more resolved components at an angular displacement comparable to that of the optical companion.
High Energy γ-ray Observations of SN 1987A
Authors: Sood R.K. , Thomas J.A. , Waldron L. , Manchanda R.K. , Rochester G.K. , Sumner T.J. , Frye G. , Jenkins T. , Koga R. , Ubertini P. , Bazzano A. , La Padula C. , Staubert R. , Kendziorra E. 
Published: July 2016

AbstractSN 1987A has been observed with a combined high energy γ-ray (50-500 MeV) and hard X-ray (15-150 keV) payload during a balloon flight on 5 April 1988 from Alice Springs, Australia. The γ-ray observations, along with our earlier ones on 19 April 1987 are the only such observations of the supernova to date. The γ-ray detector characteristics are described. The preliminary results of the recent flight and their implications in terms of the known supernova parameters are discussed.
Simple Perspectives on SN 1987A
Authors: Fu Albert 
Published: July 2016

AbstractThis conference has shown that the accumulated wealth of data on SN 1987A has enabled us to learn an unprecedented amount of physical information about a single supernova event and supernovae in general, as well as to confirm much of the heretofore established theory. While some difficult problems remain, I discuss some particularly simple and useful theoretical notions concerning the bolometric and γ-ray light curves which can be gleaned from our current body of knowledge, drawing primarily upon results of analytic work performed by W.D. Arnett and myself. Also, the work of Lamb, Melia and Loredo (1987) on neutrinos from the supernova is discussed briefly.
Chromospheres of M Dwarf Stars with Incipient Hα Emission
Authors: Robinson R. D. , Cram L. E. 
Published: July 2016

AbstractWe present observations of Hα and CaII resonance lines in 4 stars having Hα features which place them intermediately between the non-(e) and (e) classifications of dK/dM stars. There is considerable variety in the shape of the Hα line, presumably due in part to differences in rotation rates. As expected, the energy fluxes in the CaII emission lines lie between those typical of non-(e) and (e) stars. There is some evidence (especially from the binary Gl 876A) that the energy fluxes in the CaII and Hα emission lines do not vary from star to star according to a simple proportionality. An intriguing result is the apparent detection of spatially displaced chromospheric emission in Gl 907.1 and Gl 890.
A Search for Non-Radial Oscillations on Late-Type Stars
Authors: Edmonds P. D. , Cram L. E. 
Published: July 2016

AbstractThe detection of non-radial oscillations on late-type dwarf stars may require the measurement of Doppler shifts of order 10 cm s−1. We report observations using the coudé echelle spectrograph of the 3.9 m Anglo-Australian Telescope which reveal a noise level in a 1 minute integration about a factor of one hundred greater than this. We then discuss a method of imposing a set of stable reference features on stellar spectra to permit Doppler measurements of the required accuracy. The method exploits a voltage-tuned solid Fabry-Perot interferometer whose passbands are fixed by a servo-control system to the light from a HeNe laser whose frequency is polarization-stablized. The desired wavelength stability demands careful control of the voltage, temperature and tilt of the etalon.
From the Sun to the Universe—The Woolley and Bok Directorships at Mount Stromlo
Authors: Hyland A. R. , Faulkner D. J. 
Published: July 2016

AbstractThe twenty years following the Second World War saw great changes in the research interests of the Observatory at Mount Stromlo, with the early emphasis on solar and geophysical phenomena giving way to stellar and galactic astrophysics. This paper traces the development of the astrophysical research work during the directorships of Woolley, who initiated the change of direction, and of Bok, who continued it. Apart from the shift in the Observatory’s research interests, these years were distinguished by (i) an outstanding period of telescope acquisition, which saw the commissioning of the 74 inch reflector, the 50 inch (formerly the Great Melbourne Telescope), the Yale/Columbia refractor (relocated from South Africa), and the Uppsala Schmidt; (ii) an Australia-wide site-testing programme and the consequent establishment of Siding Spring Observatory with the 40 inch, 24 inch and 16 inch reflectors (the site has subsequently, of course, also become the home of the Anglo-Australian Telescope, the U.K. Schmidt, and the ANU 2.3 m Advanced Technology Telescope); (iii) the incorporation of several major technological developments into the instrument complement of the Observatory, including photo-electric photometry, coudé spectroscopy, spectrum scanners, polarization instruments, and digital computers; (iv) the establishment of the link with the Australian National University and the consequent transformation of the Commonwealth Observatory into the Mount Stromlo Observatory; and (v) the setting up of a large and vigorous graduate school, comprising, at Bok’s departure, about fifteen PhD students on course.
Elliptical Galaxies—Getting to the Heart
Authors: Sadler Elaine M. 
Published: July 2016

AbstractElliptical galaxies are at first sight a remarkably homogenous class of objects, yet some of them produce large and enormously powerful radio sources while others remain more or less quiescent. Why should this be so? What prompts the nucleus of an elliptical galaxy to become ‘active’? What, if anything, do elliptical galaxies have in common with the bulges of spirals? Here, I review some of the radio and optical properties of nearby elliptical galaxies, with special emphasis on events which take place within the central kiloparsec.
VLBI in the 1990s
Authors: Kellermann K. I. 
Published: July 2016

Abstract
Radio telescopes in more than 20 different countries on five continents are being used for VLBI observations of galactic and extragalactic radio sources, as well for applications to geodesy and geophysics. New radio telescopes and networks of radio telescopes dedicated to VLBI which are being built in the United States, the U.S.S.R., Italy, China, Poland, the U.K. as well as in Australia will greatly improve the sensitivity, resolution, image quality, and frequency coverage of the existing networks. The Mk II VLBI recording system, which is based on consumer type Video Tape Recorders, is widely used but the sensitivity is limited. Broad band recording systems are expensive, but are becoming more popular due to their much greater sensitivity. They are expected to dominate VLBI systems in the 1990s.
The first tests of an earth-to-space VLBI system took place in 1986, and by the mid 1990s dedicated VLBI antennas will be launched into earth orbit by the U.S.S.R. and by Japan in collaboration with Australia and other countries throughout the world. Space VLBI missions will give an order of magnitude improvement in resolution over the ground based VLBI networks operating at the same wavelengths.
Universal Gravity: was Newton Right?
Authors: Wright Alan E. , Disney M. J. , Thomson R. C. 
Published: July 2016

Abstract
We question Newton’s inverse square law of universal gravitation in the light of recent, alternative formulations. In addition, we present numerical simulations of galaxy interactions which were used in an attempt to distinguish between an inverse square law and an inverse linear law. We conclude that an inverse linear relation is as compatible with the observational data on interacting galaxy systems as the inverse square law.
Investigating the Halo of the LMC
Authors: Hughes Shaun M. G. , Wood Peter R. , Reid Neill 
Published: July 2016

Abstract
Recent results have shown that Long-Period Variables (LPVs) with periods in the range 100 to 250 days have ages ~ 10 Gyr. We have studied the kinematics of a sample of such variables in the Large Magellanic Cloud (LMC). A comparison with the kinematics of other populations (H I gas, CO molecular clouds, planetary nebulae, CH stars and old clusters) indicates that all populations younger than the old LPVs are dominated by a single common rotating disk, with the kinematics of the old LPVs being the first to indicate the presence in the LMC of a spheroidal population, with little or no rotation and a velocity dispersion ~ 6 times larger than that of the H I gas.
The ATNF Logo Revisited
Authors: White Graeme L. 
Published: July 2016

Abstract
The Logo of the Australia Telescope National Facility (ATNF) depicts a linear array of six antennas in the Southern Hemisphere. Precision measurement of this image implies that the Compact Array is located at latitude 37° south and azimuth 176°; this corresponds (surprisingly) to an approximately north-south array. Furthermore, the ATNF Logo was apparently prepared at LST 04h 00m.
Temporal and Spatial Characteristics of Solar Flares from Observations
Authors: Wang Jia-Long 
Published: July 2016

AbstractTemporal and spatial characteristics of solar flares are briefly reviewed in this paper. The global, temporal and spatial behaviours of flares are given first. Besides the 154-day periodicity, an 80-day periodicity of occurrence rate of large hard X-ray bursts for the period 1980 February – 1985 December, and the delay of the peak occurrence rate of large flares are pointed out, then the gregariousness of major flares is shown. In the third section, the time process and spatial structure of individual flares are shown and described according to space and ground-based observations. In the last section two problems on flare properties are discussed. (i) Previous classifications of solar flares are based generally on observations in a single spectral region. A new classification of flares based on observations in multi-spectral regions is given. (ii) Energy released in part of a loop seems to be not enough for a whole flare, and a qualitative model in which the energy is supplied by the untwisting of magnetic fields is proposed.
Sources of Enrichment
Authors: Dopita M. A. 
Published: July 2016

AbstractThe relative importance of the stellar sources contributing to the production matrix of the heavy elements up to iron is reviewed. Three main element groups may be distinguished: (a) oxygen and the alpha-process elements; (b) the iron-peak group; (c) helium, carbon and nitrogen. Each of these is produced in stars of a different mass range and in different ways, and it is shown that an examination of metallicity-metallicity relationships can be used to constrain models of the history of star formation, stellar evolution, and the initial mass function in galaxies.We can conclude that in the case of our local solar neighbourhood the initial Fe/O ratio was set by Type II supernovae, but that Type I½ supernovae were never important. Iron is produced by the Type I deflagration supernovae on a time-scale comparable to the infall time-scale of the gas. Carbon is produced by dredge-up in low-mass stars, but nitrogen is shown to be produced both in the stellar winds of massive stars, and in higher mass stars which give rise to the Type I planetary nebulae.
G54.4–0.3: Interaction of a Supernova Remnant with the Interstellar Medium
Authors: Junkes Norbert 
Published: July 2016

AbstractIn our study of the extended supernova remnant G54.4–0.3, we find a CO emission shell at about 40km s−1 radial velocity, in striking alignment with the radio continuum shell. The correspondence in position and size argues strongly for a physical connection, and allows derivation of the kinematic distance as well as the mass and density of the CO shell. The correlation with an OB association supports the value derived for the kinematic distance. Model calculations suggest that the formation of the CO shell results from a stellar wind and that the supernova remnant has expanded into the wind bubble located inside the shell.
An Explanation for the Solar Neutrino Problem—a New Mechanism of Thermonuclear Reaction
Authors: Wang Hongzhang 
Published: July 2016

AbstractA new mechanism of thermonuclear reaction is briefly introduced. It shows that a certain amount of thermonuclear reaction can take place in dense, low temperature (T < 1 × 105 K) plasmas. As most regions in the Sun are at moderate and low temperature, a sufficient amount of fusion energy is generated there. Therefore, the current standard solar models, in which the solar central temperature must be slightly lower than 15 × 106 K, must be modified, and this would make the flux of high-energy neutrinos conform with the observational results.
Supernova Rates, Starbursts and Galaxy Inclinations
Authors: van den Bergh S. 
Published: July 2016

AbstractThe supernova rate in spirals of types Sc and Sd shows a sharp peak in face-on galaxies with inclination i ≤ 25°. This suggests that most supernovae in late-type galaxies occur in rich clusters or associations that are located at the base of chimney-like structures formed by a previous generation of supernovae. These chimneys are transparent because most of the dust contained in the rising column of gas within them had previously been destroyed in the hot bubble surrounding supernovae.
Inhomogeneities in Globular Clusters
Authors: Chun Mun-Suk 
Published: July 2016

AbstractInhomogeneities in globular clusters are reviewed with the observational evidence for chemical abundance variations from star to star in individual clusters and the large-scale structural variation of clusters. The reality of the radial colour gradient is tested in 47 Tuc (NGC 104). The result shows that the observed radial colour gradient comes from the integration of the calculated colours of individual stars. The cause of this radial colour variation is the result of the concentration of evolved stars and the reddening of the main sequence in the central region. We propose that the CNO abundance gradient in the early stage of a cluster’s formation is the interpretation of the observed radial colour gradient.
New Zealand Astronomy in the 1990s
Authors: Cottrell P. L. 
Published: July 2016

AbstractThere has been a dramatic increase in astronomical research output in New Zealand over the last decade. This is set to increase with the advent of a number of new pieces of astronomical hardware over the last five years. These include the 1m telescope and associated instrumentation at Mount John and the JANZOS collaboration, with its instrumentation on Black Birch. Black Birch is also the site of the US Naval Observatory’s southern hemisphere astrometric station, where, using a transit circle instrument, they are collecting data which will form part of the International Reference Star Catalogue. As well as these ‘professional’ programs there is also a large network of amateur astronomers, who can provide extremely useful input into certain astronomical programs at the various observatories around the country and the world.A brief overview of the existing New Zealand astronomical scene will be followed by discussion of a number of new initiatives being proposed, which includes an automatic patrol telescope being developed by Carter Observatory, an expansion of the JANZOS collaboration and initial discussion about the possibility of an eastern arm for the Australia Telescope some where in New Zealand. In addition, for programs which require a long timebase of observations, extreme southerly latitudes or longitudinal coverage, New Zealand could provide a unique opportunity.