Search Publications
The UV spectrum of the narrow emission line X-ray emitting nucleus ofthe galaxy NGC 7582.
Penston, M. V.; Clavel, J.; Macchetto, F. +5 more
UV spectra of the narrow emission line, X-ray emitting nucleus of the galaxy NGC 7582 obtained with the IUE instrument show a steep featureless continuum, obeying a power-law of spectral index 3.4 + or - 0.4, close to the value of Ward et al. (1978) for the visible spectrum (spectral index equal to 3). The visual extinction on the line-of-sight of…
HD 15570 : a star intermediate between Of and WN7 ?
Willis, A. J.; Stickland, D. J.
IUE ultraviolet observations of HD 15570, classified in the visible as O4f, show the presence of N IV wavelength 1486 and He II wavelength 1640 strongly in emission, spectral characteristics which are signatures of WN stars rather than Of stars. A comparison of the UV spectra of this star with those of Xi Pup (O4f), HD 164794 (O4V) and HD 93131 (W…
IUE and balloon spectral observations of mass loss from BET Ori.
Bates, B.; Giaretta, D. L.; McCartney, D. J. +2 more
New observations are presented of the ultraviolet spectrum of Beta Ori which were obtained from the International Ultraviolet Explorer and from a high resolution, balloon-borne spectrograph. The blue-shifted, high velocity components (HVC) in the Mg II resonance lines indicate that a small deceleration of the material relative to the star has occu…
IUE observations of Large Magellanic Cloud members.
Nandy, K.; Morgan, D. H.
Spectra and flux distributions in the wavelength range 1150-3100 A are presented for six supergiants ranging from O to late B in the Large Magellanic Cloud. The stars were observed with the IUE in its low resolution mode.
Interstellar carbon monoxide in the direction of the SNR S 147.
Gondhalekar, P. M.; Phillips, A. P.
The paper examines interstellar carbon monoxide in the direction of the supernova remnant S147. The electronic bands in the fourth positive system of (C-12)(O-16) were detected in absorption in the ultraviolet spectrum of the Ble star HD 36665. The line of sight to this star is 1 deg away from the center of the supernova remnant S147 and the star …
A Large Magellanic Cloud member intermediate between Of and WN 7.
Nandy, K.; Willis, A. J.; Gondhalekar, P. M. +1 more
IUE observations of SK-65-22 (O6Iaf+) in the Large Magellanic Cloud show semiforbidden N IV 1486 A and He II 1640 A emission lines, characteristics of 'transition WR' stars, as well as the normal Of P Cygni lines. The spectrum of this star is compared with those of WN7 and normal Of LMC members and appears to be intermediate in character. The abso…
Molecules in celestial objects. I - Circumstellar CO in 9 Cephei /B2Ib/
Tarafdar, S. P.; Swamy, K. S. K.; Vardya, M. S.
The column density of interstellar CO towards 9 Cep has been determined and a tentative identification of circumstellar CO around the star made. This is the first identification of a molecule around a B star. The circumstellar column density of CO and rate of mass loss have been estimated.
Ultraviolet spectroscopy of the VELA SNR.
Danziger, I. J.; Clark, D. H.; Wood, R.
A preliminary ultraviolet spectrum secured from the IUE satellite, of a bright filament in the Vela supernova remnant, displays both emission-line and continuum components. The emission-line spectrum shows the same anomalously low carbon-line strength reported previously for the Cygnus Loop. The continuum emission may be explained in terms of norm…
Does phi Herculis have a corona ?
Stickland, D. J.; Dworetsky, M. M.
High resolution IUE spectra of Phi Herculis have been searched for indicators of a chromosphere or transition region but none have been found, which could mean that the soft X-rays observed by HEAO-1 may have an alternative origin than a conventional corona in this Hg-Mn star. The possibility that white dwarfs could be responsible for the X-rays f…
Simultaneous spectroscopic (UV MG II and AL II lines) photometric variations of zet1 SCO (HD 152236).
Clavel, J.; Bianchi, L.; Cassatella, A. +2 more
Repeated IUE observations of HD152236 show variations in the line profiles of the two Mg II doublets at about 2800 A and of the Al II lambda 1670 line. A series of puffs in the expanding envelope have been identified, implying a non-stationary mass loss process. A phase of particularly discontinuous loss of matter has been correlated with a sharp …