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Gas, dust, high energy particles and star formation in the Galactic Center
Puget, J. -L.; Lequeux, J.; Audouze, J. +1 more
The amount of gas and dust in the Galactic Center is evaluated. The COS-B and SAS-2 gamma-ray observations of the Galactic Center are discussed and limits for the flux of high-energy cosmic rays are derived from them. Consideration is given to low-energy cosmic rays which are indirectly responsible via their interaction of the interstellar matter,…
Short time changes in the terminal velocity of the stellar wind of alpha Cam ((O9.5 Ia).
Macchetto, F.; Lamers, H. J. G. L. M.; de Jager, C. +1 more
The UV spectrum of the star Alpha Cam (09.5 Ia) was observed for 72 hours continuously in September 1978, with IUE. During these three days the star shows gradual short-term changes of the edge velocity of the C IV and N V resonance lines. The change is largest for the lines formed at large distance from the star, and may be due to either UV-flux …
The ultraviolet spectrum and expansion velocity of eta Carinae from IUE observations.
Viotti, R.; Cassatella, A.; Giangrande, A.
Sunmary. The high resolution ultraviolet speotrum of Car was observel with lUE on May 22 ani 2 , 1978. High (civ, SiIV, FeIli, ani probably NV) and low ionization (Mgi, MgII, MnII, AllI, Fell, eto.) lines have been identified with absorption and/or emission oomponents. Most resonance lines have three absorption components, the interstellar line, a…
The satellite-UV spectrum of S CrA.
Wolf, B.; Appenzeller, I.
The ultraviolet spectrum (1200 to 3000 A) of the bright YY Orionis star S CrA has been observed by means of the International Ultraviolet Explorer (IUE) satellite. The strongest spectral features are identified as emission lines of C I, Mg II, Si II, Si III, C IV and Si IV and as absorption blends of Fe II, Cr II, Mn II, Ni II, Zn II and V II. Usi…
The UV spectrum of VV Cep in 1978.
Faraggiana, R.; Selvelli, P. L.
VV Cep spectra taken by IUE in June and July 1978 are examined. At this initial phase of the chromospheric eclipse following the totality of the 1977 eclipse, the chromospheric line spectrum is well developed in the region 2500-3000 A, superimposed on the spectrum of the hot companion. The flux distribution derived from the low-resolution and larg…
Ultraviolet P Cygni profiles of the C IV resonance line for O-type stars in the open cluster IC 1805.
Burki, G.; de Andres, F. L.
The ultraviolet C IV resonance lines of seven O-type stars in IC 1805 were observed with the IUE satellite in the low dispersion mode in the 1150-1950 A and 1900-3200 A wavelength ranges. The spectra showed very large and deep P Cygni profiles of the C IV resonance doublet at 1548.20 A and 1550.77 A, and P Cygni characteristics increased with bolo…
The ultraviolet spectrum of the hot halo star Feige 86.
Hack, M.
The ultraviolet spectrum of the hot halo star Feige 86 has been observed with IUE in the low-resolution mode. The energy distribution gives an effective temperature of 18000 K, in agreement with the value previously derived by Baschek and Sargent (1976) from the visual spectrum. Comparison of the line spectrum with those of two standard stars havi…
Mg II and Ca II emissions from three G dwarfs.
Rego, M.; Fernandez-Figueroa, M. J.
The stars Eta Cet, Beta CnV, and Beta Com have been observed from the ground and the IUE satellite. The Ca II and Mg II K emission line intensities have been compared and show a correlation. The full widths at the base (FWB) corresponding to the Mg II K emission are in the dispersion band of the luminosity-FWB relationship.
The UV spectrum of the possible radio star HD 26676.
Stickland, D. J.
Results are reported for low-resolution UV spectroscopy (1150-1950 A and 1850-3250 A) of the star HD 26676, which may be associated with a weak nonthermal radio source, from the IUE satellite. It is found that the energy distribution of this star appears to be that of a perfectly normal single B8 V star. It is concluded that HD 26676 is an unlikel…
Spectral characteristics of the galactic gamma radiation observed by COS-B.
Bignami, G. F.; Hermsen, W.; Bennett, K. +8 more
The ESA satellite COS-B has measured the high-energy gamma-ray emission from several regions of the galactic disk. The energy spectra of this emission have been measured. The energy spectra of the gamma radiation in the range from 50 MeV to a few GeV derived from six different longitude intervals have essentially the same shape, which resembles ne…