Search Publications
Constraints on the inclination and masses of the HDE 226868/Cygnus X-1 system from the observations.
Hartmann, L.; Davis, R.
Analyses of two high-dispersions IUE spectra of HDE 226868 (the optical counterpart of Cygnus X-1) are combined with studies of low-dispersion IUE spectra to provide a more accurate determination of the variation of C IV stellar wind absorption as a function of orbital phase. By incorporating these observational results into an analysis of the str…
The ultraviolet spectra of three N-type carbon stars.
Johnson, H. R.; Obrien, G. T.
The paper reports the successful detection of the ultraviolet spectra of three N-type carbon stars: BL Ori, TX Psc, and T Ind. Exposures of approximately 2-3 hours with the LWR camera of the IUE Satellite at low dispersion were necessary to record the ultraviolet flux. The shortward extension of the photospheric continuum is well exposed down to a…
Ultraviolet flux distributions of stars in the Orion nebula cluster.
Panek, R. J.
New observations with the IUE have been used to derive the flux distributions of 15 stars in the Orion Nebula cluster, complete over the range 0.12-3.5 microns. Extinction curves are derived for the six stars which are significantly reddened, with E(B-V) greater than 0.2. When normalized to the visual, most of these show the weak far-UV extinction…
Observations of Of-star wind variability.
Grady, C. A.; Snow, T. P., Jr.; Timothy, J. G.
Nightly variations in He II λ4686 have been observed in four Of stars, HD 152408, HD 151804, 9 Sge, and λ Cep. Three of the stars were not previously known to show such variations. In one case, λ Cep, simultaneous observations with IUE showed variations in ultraviolet resonance-line profiles during the same time period as those in He II λ4686. Thi…
Gamma-Ray Sources Observed by Cos-B
Hermsen, W.
The nature of the fine-scale structure in the gamma-ray distribution is not yet disclosed. Considerable debate is going on whether these structures which appear point-like in the data, are mainly diffuse in nature or are genuinely compact objects. Most of the uncertainty is due to the experimental limitations. A status report is presented on the e…
Gamma-ray observations toward NGC 1275 and the origin of the emissionin the infrared, X-rays, and gamma-rays.
Bignami, G. F.; Strong, A. W.
The COS B gamma-ray data used in the present search for possible emission mechanisms in the halo and nucleus of NGC 1275 show a gamma-ray excess at the galaxy's position which, if interpreted as emission from the galaxy, yields consequences concerning the origin of the hard X-rays and the IR-optical emission from the nucleus. These data are studie…
Outer atmospheres of cool stars. XV. High-dispersion ultraviolet studies of active chromospheric G-K dwarfs.
Jordan, C.; Linsky, J. L.; Simon, T. +2 more
The authors have obtained IUE ultraviolet echelle spectra of the three late-type active-chromosphere dwarf stars χ1 Ori, ξ Boo A and ɛ Eri. These are compared with previously published observations of the quiet chromosphere dwarfs α Cen A and α Cen B. The spectra indicate a gross strengthening of chromospheric and transition-region line…
Ultraviolet observations of M 1-2 (= VV8).
Feibelman, W. A.
First IUE spectrograms of the peculiar emission-line object M1-2 (= VV 8) are presented. In the wavelength region 1150-3200 A this object is characterized by emission lines superposed on a moderately strong continuum. Some ultraviolet and optical properties of M1-2 are discussed in the context of symbiotic stars and protoplanetary and planetary ne…
RW Tauri as a weak W Serpentis star.
Plavec, M. J.; Dobias, J. J.
Observations of the short-period eclipsing binary RW Tau made with the LWR and SWP cameras of the IUE satellite and with the ITS scanner at the 3-m Shane telescope of the Lick Observatory in August and October, 1982, are reported and analyzed. At total eclipse, weak excess continuous radiation in the LWR range and emission lines at Si IV (1), C IV…
Possible evidence for the driving of the winds of hot stars by ALFVENwaves.
Underhill, A. B.
Ultraviolet spectra of the supergiants Alpha Cam (09.5 Ia), HD 105056 (ON9.7 Iae), and 15 Sgr (O9.7 Iab) are compared, and it is shown that the terminal outflow velocity, TOV, of HD 105056 is one-half that of the other two stars even though HD 105056 has the highest effective temperature of the three stars. This anomaly, together with the fact tha…