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The first IUE observations of LMC X-1 (star 32).
Pakull, M.; Bianchi, L.
The first far UV observations of LMC X-1 (star 32) are presented. Form the UV continuum distribution the authors derive a value for the reddening towards star 32 of E(B-V) = 0.05 (galactic foreground extinction) plus 0.32 (extinction in the LMC). The dereddened stellar continuum can be reproduced by a model atmosphere with Teff = 35,000…
PHL 227 : the discovery of a new nova-like object.
Heber, U.; Koester, D.; Hunger, K.
The southern (13.5-mag) subdwarf candidate PHL 227 is found to be a nova-like object (UX UMa star). The line spectrum, both at visual and UV wavelengths, is strikingly similar to that of the well known UX UMa star V3885 Sgr. PHL 227 lies in the sky region of the Palomar Green survey. In this survey only two UX UMa stars (brighter than B = 16.2) so…
High-dispersion spectroscopy of the eclipse of epsilon Aurigae at visible and ultraviolet wavelengths.
Ferluga, S.; Hack, M.
Visual observations: The authors report some preliminary results of the study of three photographic spectrograms obtained during the ingress, totality and egress phases and compare them with one spectrogram taken before the start of the eclipse. They describe the characteristics of the "shell" spectrum which are similar to those observed during pr…
Gamma-ray emission from atomic and molecular gas at intermediate galactic latitudes
Strong, A. W.
Recent developments in the study of the correlations between gamma-rays and local gas tracers are described. COS-B data in the range between b of 10 and 20 deg are analyzed using simultaneous 21-cm and galaxy count data, in order to separate the roles of atomic and molecular gas. The new galaxy-count calibration of Strong (1983) is used, and the r…
IRAS and near-infrared observations of the Seyfert galaxies MCG 8-11-11, MKN 79 and MKN 279.
Roth, M.; Di Cocco, G.; Coe, M. J. +11 more
IRAS-pointed observations and near-infrared photometry of the Seyfert galaxies MCG 8-11-11, Mkn 79 and Mkn 279 are presented. Superimposed on a power law behaviour with α = -1.2, MCG 8-11-11 shows an excess at 25 µm which can be accounted for by black body emission at ≡200K from a dust emitting region of 73 pc or more. Mkn 79 has a single po…
Variations in the variability of RR Tel.
Manfroid, J.; Heck, A.
The visible-light periodicity of the very slow nova RR Tel is inferred to vary in cycles of 350- to 410-day periods, based on the uvby photometric data, IUE FES measurements, and AAVSO visual estimates. Besides a general increase in magnitude, the visible lightcurve is also marked by two events corresponding to sudden decreases of brightness in 19…
UV and optical observations of nova Sagittarii 1982.
Mazeh, T.; Netzer, H.; Cacciari, C. +6 more
Ultraviolet and optical observations of Nova Sagittarii 1982, are presented and discussed. The light curve and continuum energy distribution give a distance estimate of 4.7 kpc, visual extinction of 1±0.3 mag and Mv(max) = -6.35±0.5 mag. Simultaneous ultraviolet and optical data obtained 4 d after visual maximum, enable to study in deta…
IUE observations of comet P/Crommelin (1983 n)
Keller, H. U.; Evans, A.; Wallis, M. K. +2 more
Comet P/Crommelin has always been a difficult object to observe because of both its intrinsic faintness and its poor location in northern skies at the time of maximum activity. Observations were attempted with the International Ultraviolet Explorer (IUE) over a seven week period starting five days after the comet had reached perihelion. The nature…
Ultraviolet observations of the central star in the planetary nebula 136+5 1.
Heckathorn, J. N.; Fesen, R. A.
Ultraviolet spectra obtained with IUE are presented which confirm the Heckathorn et al. (1982) stellar candidate as the central star of the recently discovered planetary nebula 136+5°1. Spectra of the star covering the 1200 - 2000 Å range show a featureless continuum indicative of a black body temperature between 50,000 and 60,000K. Anomalously lo…
Interstellar reddeningh law towards the nucleus of H Per.
Franco, M. L.; Stalio, R.; Magazzu, A.
The extinction curves in the direction of four early-B main-sequence stars located in the nucleus of h Per (BD + 56 deg 501, BD + 56 deg 510, BD + 56 deg 516 and BD + 56 deg 517) and compared to one another and to the extinction curves derived from eight stars located in the same general area but lying at different distances. Data from UBV photome…