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Article
Faint Features of Interacting Galaxies Revealed by the Digital Coaddition of 13 Tech-Pan Films of the Virgo Cluster
We have digitally coadded APM scans of 13 Kodak TechPan films of the SE region of the Virgo Cluster of galaxies. The ≈6.2°×6.2°field of the R-band films combined with the resolution of ≈2 arcsec pixel- results in...
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Article
Truncated Collimated Flows in Abell 30, Abell 78 and the Honeycomb Nebula
Localised collimated flows of ionized gas are found in two hydrogen deficient planetary nebulae, Abell 30 and Abell 78 as well as in the Honeycomb complex of interlocking shells in halo of 30 Dor in the Large ...
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Article
Observational tests of the Interacting Winds Model of Planetary Nebulae
Numerical simulations of the evolution of Planetary Nebulae (PNe) based on the Interacting Stellar Winds models have become highly sophisticated, producing synthetic images and spectra in a number of prominent...
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Article
Smoke rings around supernova 1987a
Detailed observations of the [Oiii]5007 Å emission from the elliptical rings around SN 1987A suggest a model wherein the two faint, outer rings are due to emission from two circular toroids moving outwards (at ≤ ...
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Article
Circumstellar shocks
The presence of shocks in a wide variety of circumstellar phenomena will be illustrated and discussed.
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Article
Circumstellar matter in the symbiotic binary CH cyg during its current outburst
We present optical high-resolution spectroscopy and UBV photometry of the symbiotic binary CH Cyg during the current outburst which began in 1992 February.
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Article
Investigating the kinematics of the faint, giant haloes of Planetary Nebulae
Some interesting results from a current program of high resolution spectroscopy of the faint, giant haloes of Planetary Nebulae are presented. Observations of optical emission line profiles show that these hal...
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Article
Recent optical observations of circumstellar and interstellar phenomena
Complex motions are found over the shells which comprise the Honeycomb nebula. Evidence is presented for an episodic jet from Eta Carinae. The compact globules with radial spokes in the Helix nebula have both ...
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Article
High-speed flows in the vicinity of the Trapezium stars
[OIII] 5007 Å line profiles at high spectral and spatial resolution have been obtained at a single slit position near the Trapezium cluster in the Orion Nebula (M42, NGC1976) using the Manchester Echelle Spect...
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Article
An evolutionary model for the wolf rayet nebula NGC 2539
The main outer ring of the WR nebula NGC 2539 expands radially with velocity ≈ 26kms−1. The dynamics are modelled as the interaction of the winds from the O progenitor and the present WR stage with clumpy molecul...
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Article
Book reviews
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Article
Expanding shells within the Helix nebula (NGC 7293)?
Filter photographs and Fabry-Pérot interferograms of the Helix nebula reveal evidence of approximately spherical expansion. Heliocentric radial velocities from +44 to −51 km s−1 have been detected over the centre...
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Article
The [Sii] electron density distribution over the planetary nebula NGC 7009
Electron densities have been measured from [Sii] 6716/6731 Å line ratios for a grid of points over the surface of the planetary nebula NGC 7009 using a photon counting detector. The radial dependence of the elect...
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Article
High velocities in the interstellar complex of M17 (NGC 6618)
High-velocity features over a velocity range of 180 km s−1 have now been definitely identified on the profiles of the Hα line from the Hii region M17. A photon-counting image tube on the intermediate grating spec...
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Article
A giant Hii ring and energetic stellar winds in the large magellanic cloud
A large ring, ≃ 50 pc diameter, of Hα+[Nii] emission in the LMC has been investigated using several instruments. It is suggested that stellar winds from O and B stars could play a vital role in the formation of t...
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Article
A new large supernova remnant in the southern sky?
A faint filamentary structure on a Southern Schmidt plate is thought to be a supernova remnant.
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Article
The design, construction and performance of a large Hα and [Nii] interference filter for the SRC 48-inch Schmidt
The design, construction and performance of a 15-in. square mosaic interference filter is described. This is designed to improve the sensitivity of the SRC 48-in. Schmidt for the detection of gaseous nebulae i...
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Article
A survey of the unusual motions in M17 with a Fabry-Perot monochromator
The results of the most extensive survey ever undertaken of the profiles of the [Oiii] line over M17 are presented. These were obtained with an optically-contacted, pressure-scanned, single-etalon Fabry-Perot mon...
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Article
Observations of major ionization fronts in M42 and M8
Image tube filter photographs taken in the light of the low ionization energy [Nii] and high ionization energy [Oiii] lines of the core of M42 are presented. These were taken with the 98-in. Isaac Newton telescop...
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Article
Electronographic measurements of the ionised helium abundance in the core of the Orion Nebula
Measurements have been made with an electronographic image tube spectrograph of two helium and three hydrogen lines at twenty nine positions in the dense core of the Orion Nebula.