Search Publications
Ultra-Violet Spectroscopy of Flare Stars
Butler, C. J.; Byrne, P. B.; Andrews, A. D.
Results of an IUE satellite investigation of a selection of nearby dwarf stars of spectral type M are given. Spectra were obtained for seven stars in IUE's long wavelength range and for three stars in the short wavelength range, including both known flare stars and stars as yet not known to flare. The most prominent feature of the long wavelength …
The log N-log S graph for the COS-B galactic-ray sources.
Caraveo, P. A.; Bignami, G. F.
As a tool to the study of the collective properties of the 26 low-galactic-latitude γ-ray sources in the second CO S-B catalog their integral number-intensity relation, log N( > S, is investigated. The difficulty of accounting for the large flux errors is overcome by a simple Monte Carlo method. Especially when experimental selection effects ar…
The ultraviolet spectrum and flux of HD 152667 (=X-ray source 1653-40?)
Dupree, A. K.; Hutchings, J. B.
IUE data are presented on the massive binary system HD 152667 (spectral type BO I), covering many phases of the 8 day orbit. Low-dispersion data are used to drive T(eff), E(B-V), and the UV light curve. The secondary object is much fainter than the primary at all wavelengths. The stellar wind shows complex multiple components and appears to be uni…
The ultraviolet high-resolution spectrum of Feige 86.
Hack, M.
The high-resolution far-ultraviolet spectrum of the halo Bp star Feige 86 is studied. The energy distribution gives T(e) between 17000 and 18000 K and log g between 4 and 4.5. 1640 He II is mainly He-3. The resonance lines of NV, CIV, SiIV are present and show three components each: one shortward-shifted by about 1.5 A and one longward-shifted by …
BD +33 2642 : a galactic halo blue star observed by IUE.
Franco, M. L.; Stalio, R.
IUE observations of the high luminosity Population II blue star BD plus 33 deg 2642 have been obtained at high resolution in the short wavelength range. The star lies at a distance of 8 kpc and has a galactic latitude plus 51 deg. The stellar spectrum shows the effect of mass loss in the highly ionized resonance lines of C IV, Si III, and Si IV. A…
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…
A comparison of the MG resonance lines in AM and non AM stars of similar temperatures.
Boehm-Vitense, E.
A comparison of the Mg II resonance lines in Am and none Am stars of similar effective temperatures does not show any measurable differences. The Mg I resonance lines may be weaker in the Am stars. The mechanism reducing the Ca II K line intensities in Am stars does not work for the Mg II k and h lines.
IUE observations of two late type stars : R AQL and W Hya.
Kafatos, M.; Michalitsianos, A. G.; Hobbs, R. W.
Ultraviolet spectra of two late type M stars R Aql and W Hya were obtained with the International Ultraviolet Explorer (IUE). Spectra were obtained of R Aql near maximum (φ=0.21) and minimum φ=0.65) of the visible light curve. We find that the absolute flux intensity of the Mg II resonance doublet (2796 Å, 2803 Å) is essentially the same at these …
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.