Search Publications
Simultaneous EXOSAT-IUE observations of NGC 4151
Tarenghi, M.; Piro, L.; Perola, G. C. +9 more
NGC 4151 was observed four times in Nov. 83. The results indicate that: a) there exists a correlation between the X-ray and UV fluxes on the long term; b) the soft X-ray excess between 0.1 and 1 keV is probably steeper than expected from the leaky absorber model by Holt et al (1980); c)the spectral fit to the ME data, after correction for a soft c…
High and medium resolution spectroscopy of the X-ray transient 4U1543-47
Chiappetti, L.; White, N. E.; Kahn, S. M. +1 more
Preliminary results of an EXOSAT observation of the transient X-ray source 4U1543-47 are presented. The source was observed in August 1983, during a high state, following a Tenma alert that the source was again active. Results from the GSPC and the LE 1000 l/mm grating are presented. The spectrum is complex, but in the 2 10 keV energy range can be…
EXOSAT PSD and CMA observations of the SNR PKS 1209-52
Kellett, B. J.
EXOSAT PSD images and spectra are presented of the supernova remnant (SNR) PKS 1209-52 (G296.5+9.7. Milne 23). This source was observed for 8.5 hours in June, 1983. PSD images constructed in different energy intervals reveal that the spatial structure of the SNR is energy dependent. Comparison of the PSD and CMA images with the latest radio map of…
Spectra and time variability of GX 5-1
Pietsch, W.; Brunner, H.; Kendziorra, E. +2 more
From a short observation of GX 5-1 with EXOSAT we have derived information on spectral and temporal behaviour in the energy range 1 20 keV. The source was found to be variable on time scales from 10 s to 1 h. Describing the spectrum one is forced to assume at least two spectral components. The best fit is reached using a spectrum composed of two b…
Abell 1367 and 1060 observed with EXOSAT
Westergaard, N. J.; Norgaard-Nielsen, H. U.; Hansend, L.
Two clusters of galaxies have been observed with EXOSAT to map the distribution of cool gas. For A1367 we have detected the two brightest sources found by EINSTEIN. We confirm the identification of a X-ray source with a blue object near NGC3842. By comparing the EXOSAT and the EINSTEIN count rates we can state, either that the source is variable, …
Spectral observation of the composite supernova remnant G 29.7-0.3
Braun, R.; Koch-Miramond, L.; Rocchia, R. +3 more
The X-ray properties of the supernova remnant G 29.7-0.3 are discussed based on spectral data from the EXOSAT satellite. In the 2 to 10 keV range a featureless power-law spectrum is obtained, the best-fit parameters being: energy spectral index α=-0.77, hydrogen column density on the line of sight NH=2.3.1022 cm-2.…
Mapping of the Cygnus Loop with EXOSAT
Arnaud, M.; Ballet, J.; Rocchia, R. +1 more
Three 2.104 s observations were carried out with EXOSAT on three fields following the shock from the north to the east of the Cygnus Loop supernova remnant. Due to the softness of the source, most of the photons were collected with the LE package (CMA). For each exposure we used at least three filters (4000 Å lexan, Al-Par, boron) in or…
An EXOSAT Observation of the Morphology of the Coronal X-Ray Emission from Algol
Parmar, A. N.; White, N. E.; Culhane, J. L. +4 more
The X-ray emission from Algol is thought to originate in a corona associated with the K star in this system. We report the results of a 35 hr continuous EXOSAT observation through secondary optical eclipse that was designed to measure the structure of the corona. No obvious X-ray eclipse was seen. The spectrum measured by the ME gives a temperatur…
Optical Observations of Serendipitous EXOSAT Sources in the Coma Cluster
Branduardi-Raymont, G.; Mason, K. O.; Martin, C. +2 more
A ∼7 hour observation of the central part of the Coma Cluster of galaxies has been performed with the EXOSAT LE telescopes and CMA detectors. Five serendipitous sources are detected within the inner 35 arcmin radius of the field. Optical spectroscopy demonstrates that at least three of these are background AGN not associated with the cl…
The Discovery of Low-Level Iron Line Emission from CYGNUS-X-1
White, N. E.; Barr, P.; Page, C.
We present the results of seven observations of the X-ray spectrum of Cyg X-1, made with the GSPC on board the EXOSAT observatory. We report the discovery of an iron emission line in its spectrum. The likely origin of this feature is discussed.