Far-ultraviolet stellar photometry: A field in Orion
Far-ultraviolet photometry for 625 objects in Orion is presented. Thesedata were extracted from electrographic camera images obtained duringsounding rocket flights in 1975 and 1982. The 1975 images were centeredclose to the belt of Orion while the 1982 images were centeredapproximately 9 deg further north. One hundred and fifty stars fell inthe overlapping region and were observed with both cameras. Sixty-eightpercent of the objects were tentatively identified with known starsusing the SIMBAD database while another 24% are blends of objects tooclose together to separate with our resolution. As in previous studies,the majority of the identified ultraviolet sources are early-type stars.However, there are a significant number for which no such identificationwas possible, and we suggest that these are interesting objects whichshould be further investigated. Seven stars were found which were brightin the ultraviolet but faint in the visible. We suggest that some ofthese are nearby white dwarfs.
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Broad-band photometry of selected southern ultraviolet-bright stars.
Not Available
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The globular cluster system of the Galaxy. I - The metal abundances and reddenings of 70 globular clusters from integrated light measurements
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1980ApJS...42...19Z&db_key=AST
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A classification of star clusters in the Magellanic Clouds
Four-color photometry of the integrated light from 61 star clusters inthe Magellanic Clouds, together with a rediscussion of Danziger'smultivariate spectrophotometric data for some of these same clusters,have made possible for the first time an intelligible classificationscheme for their integrated spectra. It is found that the integratedspectra of populous star clusters in the Magellanic Clouds may bearranged in a one-dimensional sequence in such a way, that on traversingthe sequence, all spectral features behave regularly - not necessarilymonotonically, but as smoothly as can be expected from the magnitude ofobservational error. The character of the spectral variations along thesequence suggests that both cluster age and chemical composition varysmoothly as the sequence is traversed. The newly discovered sequence isdistinctly different from the analogous one for star clusters of theGalaxy, and this fact is interpreted as indicating that the relationbetween epoch and average chemical composition of the interstellarmedium is qualitatively different in different stellar systems.
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Interaction between the Barnard Loop Nebula and the interstellar magnetic field
New observations of the linear interstellar polarization of starlightare used to study the geometric structure of the interstellar magneticfield in the vicinity of the Barnard Loop Nebula in Orion. The observedcomplex field structure cannot be explained by a simple radial expansionof a conducting gaseous shell into an initially parallel field. Asatisfactory fit of the observations can be obtained by assuming thatthe interstellar gas in Orion is suspended in an interstellar 'magneticpocket'. It is suggested that the formation of the observed denseinterstellar clouds and very young stars in the Orion aggregate is aresult of the local structure of the interstellar magnetic field.
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UBV photometry of star clusters in the Magellanic Clouds.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1968AJ.....73..569V&db_key=AST
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UBV-Helligkeiten von acht Sternpaaren am Äquator
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