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Column Densities of Interstellar Matter in the Direction of the Star Kappa-Cassiopeiae B1IA

Mentese, H. Huseyin

We have studied the interstellar column densities in the direction of the star κCas with the IUE high resolution SWP spectrum so as to see the relations of element depletions with condensation temperature and compare our results with the interstellar column densities in the directions of the other B-type stars obtained with the COPERNICUS satellit…

EXOSAT X-ray and Optical Observations of the X-ray Source EXO 020528 + 1454.8 = G 035 - 027

Richter, G. A.; Hudec, R.; Wenzel, W. +8 more

Results of the Exosat X-ray observations and quasi-simultaneous optical photographic photometry of the X-ray source EXO 020528 + 1454.8 = 1 E 0205 + 149 are presented and discussed. The results indicate that the source is identical to the Lowell proper motion object G 035 - 027, a pair in which at least one but more probably both members are dMe f…

The flux variability of the Seyfert galaxy NGC6814 as observed with exosat

Branduardi-Raymont, G.; Mittaz, J. P. D.

We present five EXOSAT observations of the Seyfert galaxy NGC6814. The source is found to be variable at both soft (LE) and medium (ME) X-ray energies. The most remarkable characteristics of this variability are the regular recurrence of flares at 12000s intervals during a 1-day long ME observation, a dip in the ME flux by a factor of 2 in ~ 300 s…

The circumstellar environment of the Herbig Ae/Be stars. The case of AB Aurigae.

Fonti, S.; Blanco, A.; Strafella, F.

The possibility that the near-infrared excess observed for AB Aur is due to free-free emission coming from a circumstellar H I region is investigated. The analysis of absorption lines (mainly of Fe II) present in IUE spectra shows that both the derived column densities and the excitation temperature (about 2000 K) indicate the presence of a conspi…

Meeting Reports: Colloquium on HIPPARCOS Scientific Aspects of the Input Catalogue Preparation and A Celebratory Symposium on a Decade of UV Astronomy with the IUE Satellite

Mattei, Janet A.

The colloquium HIPPARCOS Scientific Aspects of Input Catalogue Preparation, held in Sitges, Spain, January 25 - 29, 1988, is described. Also described is a celebratory symposiun on a Decade of UV Astronomy with the IUE Satellite, held April 12 - 15,k 1988 in Greenbelt, MD. Brief description of the European astrometric satellite HIPPARCOS and the u…

Detection of transient periodicity in an EXOSAT observation of NGC4151

Piro, L.; Perola, G. C.; Fiore, F. +1 more

Fourier analysis of an EXOSAT (ME) 30000 s observation of the Seyfert 1 galaxy NGC 4151 revealed a transient periodical phenomenon (period 131 +/- 1 s and duration of a few thousand seconds) with a probability of a chance occurrence of the peak in the power spectrum of 2 10^-3. Analysis of short data segments provides further evidence of…

Results of high resolution soft X-ray spectroscopy of hot white dwarfs with EXOSAT

Paerels, Frits; Heise, John

We present the final results of the high resolution X-ray spectroscopy of hot white dwarfs, obtained with the 500 lines mm^-1 Transmission Grating Spectrometer on EXOSAT. These data, which are unique in wavelength coverage, spectral resolution, and statistical quality, have offered us the first detailed look at the photospheric X-ray spe…

Erratum - a 23H EXOSAT Observation of the X-Ray Pulsar 1E:2259+586 and the Associated Supernova Remnant G:109.1-1.0

Coe, M. J.; Dennerl, K.; Hanson, C. G. +1 more

SC 2059-247 : no evidence for cluster evolution or extreme X-ray properties.

Kaastra, J. S.; de Korte, P. A. J.

The southern cluster SC 2059-247 has been observed by the X-ray satellite EXOSAT. The cluster has a high luminosity and cooling mass flow and a small core radius, but it has neither exceptional properties compared to other clusters, nor does it show signs of evolution effects, as was concluded from earlier Einstein observations.

ISM Chemical Abundances in Two Intermediate-Velocity Clouds in the Line of Sight to SN 1987A

Bohm-Vitense, Erika; Morgan, Siobahn

The earliest IUE high-resolution spectra of SN 1987A have been studied and reveal the presence of several clouds in the line of sight to the LMC. In particular, there are two clouds with radial velocities of ~ 130 km s^-1^ and ~ 180 km s^-1^. These clouds' velocities are between those of Galactic clouds at 0-80 km s^-1^ and those of LMC gas at ~27…