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IUE and other new observations of the slow nova RR Tel.
Penston, M. V.; Jordan, C.; Macchetto, F. +8 more
IUE satellite UV spectra of RR Tel covering 1150-3200 A at high and low dispersion through both large and small apertures are reported, and a list of 431 lines is presented which gives measured wavelength, intensity, and full width at half maximum. Over three-quarters of the lines are identified, and a correlation is noted between line width and i…
Extreme variability in the Be-type, periodic recurrent X-ray transient AO538-66 : a highly eccentric interacting binary.
Howarth, I. D.; Charles, P. A.; Willis, A. J. +6 more
The recurrent X-ray transient sources represent a substantial class of galactic objects which are difficult to study extensively. They can be divided into two groups on the basis of their optical primaries, including the low-mass systems which are optically faint outside their outbursts, and those with high masses. White and Carpenter (1978) disco…
Ultraviolet and optical observations of the dwarf novae VW and WX Hydri during outburst.
Schwarzenberg-Czerny, A.; Pringle, J. E.; Wade, R. A. +3 more
Simultaneous spectrophotometry is presented in the range 1200-7000 A of the dwarf novae, at quiescence and maximum. The continuum spectra are compared with the standard model disk spectrum and, with one exception, the fit is poor. The assumptions that the disk is both steady-state and blackbody are reconsidered, and it is pointed out that a nu to …
A study of the low-mass X-ray binary HZ HER/HER X-1 using IUE and optical data.
Howarth, I. D.; Wilson, B.
An extensive body of uniformly extracted IUE spectrophotometry of HZ Her/Her X-l is presented. To interpret these data a light-curve synthesis model comprising a distorted, X-ray heated primary accompanied by an accretion disc is developed. Roche geometry is used for the star, and the X-ray shadow thrown by the disc accounted for. The model's para…
MR 2251-178 : a nearby QSO embedded in a giant H II envelope.
Tarenghi, M.; Boksenberg, A.; Bergeron, J. +1 more
Spectra of MR 2251-178 and surrounding galaxies were obtained and analyzed. The kinematics of the extended region, the spectra of the QSO and nebulosity, and the galaxies of the surrounding cluster are discussed. The QSO lies in the nucleus of a galaxy having a gaseous component of very high ionization, high temperature and relatively low abundanc…
Analysis of nebulosity in the planetary nebula NGC 40.
Seaton, M. J.; Clegg, R. E. S.; Torres-Peimbert, S. +1 more
Optical and IUE spectra of a bright region of nebulosity in the planetary nebula NGC 40 have been combined for an analysis of the physical conditions and abundances in the nebula. Resulting abundances are typical of planetary nebulae and indicate that the nebulosity does not share the extreme abundances of the Wolf-Rayet WC8 central star. The cont…
The symbiotic star H1-36.
Allen, D. A.
The high-excitation emission-line star H1-36 is investigated using optical and infrared spectrophotometry. It is established that H1-36 may be classified as a symbiotic star due to the presence of a variable M giant. The observations are analyzed in terms of the usual binary model for symbiotic stars in which an unseen star is heated by accretion …
IUE observations of W UMa-type stars.
Vilhu, O.; Rucinski, S. M.
IUE (International Ultraviolet Explorer) low-resolution SWP images of the contract binaries 44i Boo, VW Cep, W UMa, V566 Oph, AW UMa, V502 Oph, Epsilon CrA, RR Cen and the very close non-contact binary ER Vul have been studied. The results are compared with other UV and soft X-ray data and it is found that the stellar activity within this group is…
The ultraviolet variability of NGC 3783.
Willis, A. J.; Wilson, R.; Barr, P.
The results of three years of monitoring the spectral variability of the type 1 Seyfert galaxy NGC 3783 with IUE spacecraft instrumentation are reported. Techniques for fitting power laws to the observed wavebands are described, noting the monitoring was carried out in the 1150-3150 A region. The continuum was found to vary by a factor of ten over…
Phase-dependent UV spectra of UX Ursae Majoris.
Jameson, R. F.; King, A. R.; Sherrington, M. R. +1 more
The authors report phase-dependent UV spectra of UX UMa. The behaviour of the continuum during eclipse is as expected for an optically thick accretion disc. The authors confirm that the C IV λ1549 emission line is not eclipsed, and show that several other lines undergo partial or total eclipses. This behaviour is shown to be consistent with simple…