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X-Ray Continuum with an Iron Emission Line from the Radio-Quiet Quasar PHL 909
Ghosh, K. K.; Soundararajaperumal, S.
Results of the spectral analysis of the X-ray (0.1 - 10 keV) spectrum of the radio-quiet quasar, PHL 909, are presented. A spectrum of this quasar which was observed on 1984/349, was obtained from the EXOSAT archives. Different models were used to fit the ME and LE+ME data. Fit parameters to the ME data show a steep spectral index for this quasar …
Ultraviolet Colors of Old LMC Clusters
Cowley, A. P.; Hartwick, F. D. A.
New ultraviolet spectra for five red LMC globular clusters have been obtained with IUE. These have been supplemented with archival spectra for eleven old LMC clusters. These data strengthen and extend the UV-color vs. age relation for clusters older than 10^9 years, but do not offer much precision in age determination, presumably because the ultra…
The Composite Nature of the Peculiar Star HR 6560 (HD 159870)
Wegner, Gary; Cowley, Charles R.
Ground based high dispersion photographic spectra and ultraviolet spectra obtained with the International Ultraviolet Explorer (IUE) satellite are described and employed to determine the nature of the peculiar star HR 6560 (HD 159870). Previously this object had been described as both a composite system and a strong Fm star. We inter-compare the U…