Search Publications
E(B-V) extinction values for 24 planetary nebulae derived from IUE data.
Feibelman, W. A.
Excellent agreement was found for E(B - V) values for nine planetary nebulae observed in common by IUE and ANS, derived from a strong 2200A absorption feature. E(B - V) values for seven additional objects with moderately strong 2200A absorption were determined. A third group of eight planetary nebulae for which the 2200A absorption feature is marg…
Luminosities and masses for three central stars of planetary nebulae in the Magellanic clouds from ultraviolet spectroscopy with the IUE.
Gull, T. R.; Stecher, T. P.; Maran, S. P. +2 more
Physical parameters of the central stars of the planetary nebulae (PN) P40, N2, and N5 are determined from UV observations by the IUE spacecraft and emission line-data. The observations took place on May 23 and 26, 1981. Derived properties, such as the H-beta, color excess, nebular hydrogen emission, helium emission, and stellar continuum emission…
Interstellar extinction in the Small Magellanic Cloud.
Nandy, K.; Willis, A. J.; Wilson, R. +5 more
IUE observations of three considerably reddened stars located near the core of the Small Magellanic Cloud and of two comparison stars which are also SMC members are presented. This region contains a considerable amount of dust. The UV spectrum of one of the reddened stars (BBB 338) shows the 2200-A wavelength feature characteristic of the Galactic…
Ultraviolet, visual, and infrared observations of the WC7 variable HD193793.
Savage, B. D.; Fitzpatrick, E. L.; Sitko, M. L.
Low-resolution IUE data are used to explore the ultraviolet extinction toward the Wolf-Rayet star HD 193793 and to search for ultraviolet variability that might relate to the infrared variability. High-dispersion IUE observations are used to investigate the nature of the stellar wind of the star and to search for anomalies in the interstellar line…
On the detection of abundance stratifications in peculiar stars through the curve of growth method
Alecian, G.
Theoretical curves of growth for manganese are computed for an atmosphere with T(eff) = 12,000 K and log g = 4. It is shown that the curves of growth may be strongly affected by the presence in the atmosphere of a plane parallel layer where manganese is overabundant. The theoretical results are compared with observations of the Hg-Mn star Nv Her. …
On excitation through radiative pumping of the Fe II UV-mult. 191 lambda lambda 1785-88 angstrom observed with the IUE during the eclipse of 32 Cyg.
Reimers, D.; Hempe, K.
We show by means of high-resolution lUE spectra of 32 Cyg during and shortly after eclipse - there is a total eclipse of the B star in the UV - that the Fe II UV-multiplet 191 is pumped via the Fe II resonance UV-multiplet 9 λλ1260-76 Å. We show directly from observations 1. that all absorbed multiplet 9 photons are emitted as Fe II UV Mult. 191 l…
Ultraviolet observations of the 1980 eclipse of the symbiotic star CICyg.
Kafatos, M.; Stencel, R. E.; Michalitsianos, A. G. +1 more
The paper presents secular and eclipse variations of ultraviolet lines and continua in the course of nearly a complete orbit of CI Cygni. High-excitation resonance lines show minimal effects of eclipse, while intercombination lines have faded and show pronounced but nontotal eclipse effects. The observations are examined in terms of mass transfer …
On the search for transition zone lines in late A type stars.
Praderie, F.; Crivellari, L.
Observations of the 1400-1800 A region in late A type stars are presented, which were obtained using the IUE satellite at low and high resolution. The calibrated energy distribution is derived and presents a large variation with wavelength in the spectral range due to Si I photoionization discontinuities. Emission lines formed in the transition re…
Magnesium emission variability among late-type giant stars.
Stencel, R. E.; Mullan, D. J.
Profiles of the Mg II h and k emission features in the spectra of 21 late-type giant stars were obtained. Emission strengths were separately measured in the shortward (S) and longward (L) components. Variations in total emission intensity (S + L) can be interpreted as evidence for variations in the rate of mechanical energy deposition in the chrom…
IUE observations of the Lac object AO 0235+164.
Boksenberg, A.; Penston, M. V.; Snijders, M. A. J. +1 more
AO 0235+164 was observed with IUE during its February 1979 outburst. The object was detected in both the short and long wavelength cameras. Hydrogen Lyman-alpha absorption in the z = 0.524 system is detected with equivalent width of 62 + or - 28 A (1-sigma error). From this and previous 21-cm data, the spin temperature of the absorbing material is…