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Coordinated optical, ultraviolet, radio and X-ray observations of SN 1979c in M 100.
Tarenghi, M.; Panagia, N.; Parmar, A. N. +24 more
Coordinated optical, ultraviolet, radio and X-ray observations of supernova 1979c in M 100 made in the first six weeks after its discovery are presented and discussed. On the basis of optical data, which indicate a maximum magnitude of -19.4, a decay rate of 0.046 magnitudes/day, a total radiative energy of 7 x 10 to the 49 erg, and optical lines …
Detailed ultraviolet observations of the quasar 3C 273 with the IUE.
Tarenghi, M.; Perola, G. C.; Boksenberg, A. +17 more
The paper analyzes the nine spectra of the quasar 3C 273 obtained with the International Ultraviolet Explorer in order to combine them and to obtain a high signal-to-noise spectrum between 1100 and 3300 A. An analysis was then made of the emission line intensity ratios and of the continuous energy distribution; evidence was found for thermal contr…
Spectrophotometry of dwarf novae in the wavelength range of 1250-7500A.
Pringle, J. E.; Bath, G. T.; Whelan, J. A. J.
The paper presents spectrophotometric observations of three southern dwarf novae BV Cen, EX Hya and VW Hyi in the wavelength range 1250-7500 A. BV Cen and EX Hya were observed in quiescence and VW Hyi on the decline from outburst. The received energy flux for BV Cen peaks at visible wavelengths, where the spectrum of a late G-star is evident. Both…
Ultraviolet spectra of planetary nebulae. I. The abundance of carbon in IC 418.
Harrington, J. P.; Lutz, J. H.; Seaton, M. J. +1 more
IUE observations of IC 418 give fluxes in the lines C III λ1908, C II] λ2326, [O II] λ2470 and Mg II λ2800. Fluxes on the scale of F(Hβ) = 100 are obtained using a computed [O II] branching ratio F(λλ7320,30)/F(λ2470) and an observed ratio F(λλ7320, 30)/F(Hβ). The deduced carbon abundance is log {C} = 8.85 ± 0.2 compared with log {C} = 8.67 ± 0.1 …
The UV spectrum of AE Aqr.
Jameson, R. F.; King, A. R.; Sherrington, M. R.
Ultraviolet spectra of the cataclysmic variable AE Aquarii obtained by the IUE satellite are reported. They show strong emission lines on a weak continuum. It is shown that while Mg II, Ca II and some L-alpha emission probably arise in optically thin regions of the accretion disc, the higher ionization species must be radiatively produced outside …
IUE observations of interstellar SI IV and C IV lines observed in thespectra of Wolf-Rayet stars.
Willis, A. J.; Wilson, R.; Smith, L. J.
Recent IUE observations of Wolf-Rayet stars show narrow absorption lines in the highly ionized species of Si IV and C IV. These are observed in the spectra of 10 WR stars which are being studied as part of an extensive investigation of this stellar class with the IUE satellite. The strengths of the sharp Si IV and C IV undisplaced absorption lines…
S I emission in EUV spectra of late-type stars.
Jordan, C.; Brown, A.
Observations of strong neutral sulfur emission lines in the EUV spectra of late-type giant and supergiant stars are discussed. Low- and high-resolution spectra of Alpha Tauri and Beta Gru are presented which demonstrate the contribution of the S I (UV 9) multiplet to the observed features at approximately 1296 A as well as the strong O I multiplet…
Ultraviolet observations of WZ SGE in outburst.
Fabian, A. C.; Pringle, J. E.; Stickland, D. J. +1 more
The paper describes low and high-resolution UV spectroscopic observations of the recurrent nova WZ Sge obtained during its December 1978 outburst. The observations were made during outburst with the IUE satellite. Low-resolution images obtained on December 14 and 24 are discussed. The continuum on both days may be fitted by a power law or an optic…
Ultraviolet spectra of planetary nebulae. II. The young PN IC 4997.
Flower, D. R.
Observations of the planetary nebula IC 4997 made with the International Ultraviolet Explorer satellite are analyzed in conjunction with visual photoelectric observations. The extinction to the nebula and the electron temperature and density are deduced from the relative intensities of lines emitted by O(+) and O(2+) ions. The relative abundance o…
Ultraviolet studies of the Magellanic Clouds-I. Interstellar lines inthe spectra of FD 70 and SK -71 45.
Nandy, K.; Willis, A. J.; Gondhalekar, P. M. +1 more
High dispersion ultraviolet spectra of the two LMC members, HD 38282 (FD 70) and HD 269676 (SK-71-45), have been obtained with IUE. Velocity profiles have been presented of the numerous interstellar lines observed in the spectra of these stars and associated with the absorption in both the Galaxy and the LMC. In both lines-of-sight well defined in…