Search Publications
IUE results on the AM Herculis stars CW 1103, E 1114 and PG 1550.
Szkody, P.; Panek, R. J.; Liebert, J.
IUE data are presented on three AM Her stars (CW 1103 + 254, E1114 + 182, and PG 1550 + 191) which are used in conjunction with optical and IR fluxes to study the accretion characteristics of these systems in relation to other polars.The time-resolved IUE spectra of CW 1103 show that the column contributes little to the UV, while the white dwarf, …
The galactic gamma-ray distribution - Implications for galactic structure and the radial cosmic-ray gradient
Harding, A. K.; Stecker, F. W.
The radial distribution of gamma ray emissivity in the Galaxy was derived from flux longitude profiles, using both the final SAS-2 results and the recently corrected COS-B results and analyzing the northern and southern galactic regions separately. The recent CO surveys of the Southern Hemisphere were used in conjunction with the Northern Hemisphe…
Analysis of ultraviolet atmospheric eclipses in the Wolf-Rayet binaryCV Serpentis.
Cherepashchuk, A. M.; Eaton, J. A.; Khaliullin, Kh. F.
The authors have obtained ultraviolet spectra covering one-half of an orbital cycle of CV Ser. Marked phase effects have been detected in which ultraviolet absorption lines are greatly strengthened when the W-R star is in front. No eclipses are seen longward of 2300 Å, while below 2000 Å blanketing by numerous lines, spread out in frequency by the…
Cepheid distances from blue main-sequence companions.
Bohm-Vitense, E.
The author determines the absolute visual magnitudes of main-sequence Cepheid companions from their effective temperatures. These are obtained by comparing the measured relative energy distributions with model atmosphere energy distributions. Assuming an average galactic extinction law, it is found that the distance moduli for the Cepheids should …
The unexpected ultraviolet variability of Herbig-Haro object 1.
Shull, J. M.; Brugel, E. W.; Bohm-Vitense, E. +1 more
The line fluxes of the C IV 1550 A and semiforbidden C III 1909 A emission lines in HH 1 are noted to have monotonically decreased by factors of 4-6 between 1979 and 1983, despite a lack of indications of optical range changes. The thickness of the shocked layers and preshock density can be estimated on the basis of these rapid changes, with resul…
Extreme Be stars in the Magellanic Clouds.
Humphreys, R. M.; Garmany, C. D.
In the course of a spectroscopic investigation of the O-type stars in the Magellanic Clouds, a population of luminous Be stars was serendipitously encountered. They are here referred to as extreme Be stars, following the terminology used by Schild (1966) for a population of Be stars in the region of h and Chi Persei which lie significantly above t…
An analysis of scattered light in low dispersion IUE spectra.
Clarke, J. T.; Basri, G.; Haisch, B. M.
A detailed numerical simulation of light scattering from the low-resolution grating in the short wavelength spectrograph of the IUE Observatory was developed, in order to quantitatively analyze the effects of scattering on both continuum and line emission spectra. It is found that: (1) the redistribution of light by grating scattering did not appr…
The newly discovered eclipsing supergiant 22 Vulpeculae.
Kondo, Y.; Ake, T. B.; Parsons, S. B.
Spectra obtained with the IUE satellite have led to the discovery of a new atmospheric eclipsing binary belonging to the ζ Aurigae class of stars, 22 Vul. This system is unique in that it is the first one found with a G-type primary (G3 Ib-II), while the spectral type of the secondary is the latest (B9) and its period is the shortest (249 days) of…
IUE spectra of GO V-G5 V solar-type stars.
Basri, G.; Haisch, B. M.
An atlas of IUE short-wavelength spectra for a set of 14 bright G0 V-G5 V stars are presented, and it is shown that these manifest a range of qualitatively different chromospheric and transition region spectra and significant differences in radiative flux originating at the temperature minimum level. A comprehensive survey of observational data an…
The distribution of the local interstellar medium derived from MG II column densities towards seven cool stars.
Molaro, P.; Franco, M. L.; Beckman, J. E. +2 more
High resolution spectra containing the Mg II h and k resonance doublet have been obtained using the long wavelength spectrometer of IUE, for 7 late-type stars (F0 to G8). In one of these stars, β Hyi, two sharp absorption features were detected against the chromospheric emission cores. Using the study of Crutcher (1982) the authors can employ the …