Search Publications
The type II SN 1979c in M 100 and the distance to the Virgo cluster.
Wills, B. J.; Branch, D.; Falk, S. W. +3 more
Intensity calibrated optical spectrophotometric observations of supernova 1979c in M100 were obtained between April 22, 1979 and November 24, 1979. The time development of the spectrum appears typical for type II events, except perhaps that the H-alpha feature never appears in P Cygni form. Synthetic spectra computed using a blackbody photosphere …
NGC 7714 - The prototype star-burst galactic nucleus
Sramek, R. A.; Weedman, D. W.; Feldman, F. R. +3 more
New X-ray, ultraviolet (IUE), optical, and radio (VLA) observations are presented for the bright nucleus galaxy NGC 7714. All data are explainable as resulting from intense star-formation activity in this nucleus - a star burst. The X-ray and radio luminosities are explained by supernova remnants arising from the massive stars, and approximately 1…
Mass loss rates from O stars in OB associations.
Conti, P. S.; Garmany, C. D.; Olson, G. L. +1 more
The considered investigation is concerned with an extension of an analysis of the spectra of 31 O type stars observed with the International Ultraviolet Explorer (IUE) satellite to include excited as well as resonant lines. The investigation makes use of the methods developed by Olson (1981). Most of the stars are unevolved cluster members, a grou…
Ultraviolet stars in the Orion Nebula and toward HD 147889.
Savage, B. D.; Bohlin, R. C.
The International Ultraviolet Explorer (IUE) was used to obtain low resolution absolute ultraviolet energy distributions for the four Trapezium stars Theta(1) Orionis A, B, C, and D, Theta(2) Orionis A and B, HD 147889, and several unreddened standard stars. The observations for Theta(1) Orionis B reveal a peculiar extended object. The measurement…
Ultraviolet interstellar extinction in the Large Magellanic Cloud using observations with the international ultraviolet explorer.
Koornneef, J.; Code, A. D.
Ten early-type supergiants in the Large Magellanic Cloud (LMC) have been observed with the International Ultraviolet Explorer (IUE). The spectra (1150-3200 A) are shown, and their photometric properties are discussed. It is confirmed that the LMC interstellar extinction law for these stars deviates significantly from the average galactic law in th…
The optical and ultraviolet spectrum of the planetary nebula NGC 2440.
Czyzak, S. J.; Shields, G. A.; Keyes, C. D. +1 more
New measurements of the optical and ultraviolet emission-line intensities of the high-excitation planetary nebula NGC 2440 in the wavelength range 1240-8578 A are analyzed with the aid of photoionization models. The observed O III and N II forbidden-line temperatures (13,800 K and 10,000 K, respectively) differ by more than the models predict. Inc…
Physical conditions in the nucleus of M 81.
Torres-Peimbert, S.; Peimbert, M.
IUE and visual observations of the emission lines in the nucleus of M8 1 are presented. The permitted lines show broad and narrow features qualitatively similar to those in Seyfert galaxies. The observed luminosity for the broad component is L(Hβ) = 7.4 × 1037 ergs s-1, which is about two orders of magnitude smaller than in t…
Ultraviolet observations of hot stars with circumstellar dust shells.
Savage, B. D.; Sitko, M. L.; Meade, M. R.
Absolute fluxes over the wavelength range 1200-3200 A are presented for 13 normal early-type stars and 12 early-type stars known to have large IR excess; the data were obtained to study the UV spectral modifications produced by absorbing circumstellar dust particles. It is found that all the Be/shell stars whose spectral types are later than B6 ex…
Coordinated X-ray, ultraviolet and optical, observations of AM Her, UGem and SS Cyg.
Branduardi-Raymont, G.; Fabbiano, G.; Raymond, J. +3 more
Simultaneous and quasi-simultaneous optical, UV and X-ray observations of the accreting degenerate dwarf stars AM Herculis, U Geminorum and SS Cygni are reported. The observations were obtained in March 1979, by instruments on board the Einstein Observatory and the IUE satellite, and optical properties were monitored on the ground. AM Her was foun…
Extragalactic H II regions in the UV : implications for primeval galaxies.
Terlevich, R.; Meier, D. L.
Three extragalactic regions of rapid star formation with redshifts great enough to separate the Lyman-alpha region from geocoronal Lyman-alpha have been observed with the IUE satellite. Only the low metal abundance object had detectable Lyman-alpha emission with Lyman-alpha/H-alpha of about 6; the other two have Lyman-alpha/H-alpha less than 0.6 (…