Search Publications
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.
The Spectral and Temporal Variability of the X-Ray Transient 4U1630-47
Stella, L.; Parmar, A. N.; White, N. E.
We present the results of four observations made by the European Space Agency's EXOSAT Observatory of the X-ray transient 4U1630-47 during its 1984 outburst. We observed marked spectral changes as the source decayed from a maximum observed intensity of 8×10-9 erg/cm2/sec (1.5 10 keV). The spectrum could be modelled by a soft …
2 10 KeV spectra of Crab-like SNR's as observed by EXOSAT
Smith, A.; Davelaar, J.
The EXOSAT ME observations of 3C58 and G21.5-0.9 are presented. The data for these objects is considered in conjunction with the data available from EXOSAT for the Crab-like SNR's Crab and Vela X. The objects have single power law spectra with a range of spectral indices of 0.6 to 1.5, 3C58 and Vela X being similar to the Crab whilst G21.5-0.9 and…
Some crucial X-ray observations — One or two SNR(s) in Crux?
Caraveo, P. A.; Bignami, G. F.; Mereghetti, S. +2 more
A new EXOSAT (LE/CMA) observation of the region in Crux (R.A. ∼11h 45m, Dec. ∼-62°) where Markert et al. (1981) reported the existence of two x-ray SNR's is presented. After “cleaning” the CMA field from the point source component, due to the UV emission of the numerous stars in the field, the smoothed x-ray contours are compared to the 408 MHz ra…
A New View of the Galactic Plane with EXOSAT
Warwick, R. S.; Watson, M. G.; Turner, M. J. L. +1 more
A new X-ray image of the galactic plane has been produced using the 45 arcmin square field of view of the Medium Energy Instrument on EXOSAT. This image shows a total of 64 sources including 18 new ones which include the first observation of persistent emission from the globular cluster bursters Terzan 1 and Terzan 5. The most important discovery …
EXOSAT Observations of Bursts from 2S1636-536 - Burst Morphology
Turner, M. J. L.; Ohashi, T.; Breedon, L. M.
In two observations with the EXOSAT ME a total of 11 bursts were detected; 7 in July and 4 in May 1984. In terms of rise time and peak count rate there are only 2 kinds, those with a sharp rise and peak count rate of 500 cts/sec/detector and those with a slow rise and a peak count rate of 200 cts/sec/detector. The spectral analysis of these bursts…
H0323+022 - Classification as a Bl-Lacertae and EXOSAT Coordinated Observations
McHardy, I.; McClintock, J. E.; Remillard, R. +18 more
The object H0323+022 (Doxsey et al. 1983) has been shown to be a BL Lac object by virtue of a diversity of observational characteristics at radio, optical, and x-ray wavelengths, in agreement with the conclusion of Margon and Jacoby (1984). Multi-frequency coordinated observations of this highly variable object with EXOSAT in September 1984 found …
Coordinated EXOSAT and Optical Observations of the X-Ray Burster 4U1737-44
Charles, P. A.; Corbet, R. H. D.; Smale, A. P. +2 more
We present the first results of an EXOSAT observation of the low-mass X-ray burster 4U1735-44. The ME data show low-amplitude variations in the persistent flux including two 5% dips separated by ∼4 hours. The structure of the single observed burst is briefly described. Five hours of simultaneous B-band photometry were obtained at SAAO with 12 minu…
EXOSAT spectra of some bright QSO's
Tennant, A. F.; Stewart, G. C.; Shafer, R. A. +1 more
This paper reports on EXOSAT observations of four bright QSO's and active galaxies. The QSO PHL 1657 has a simple spectrum that can be fit with power law plus some low energy absorption. A soft excess is observed for both MR 2251 and E 1352.24+1830. Finally, PKS 2126-158 was detected and the results are consistent with a 0.7 energy index.
The Quiescent Spectrum of 2S1636-536
King, A.; Turner, M. J. L.; Breedon, L. M. +1 more
During the EXOSAT observation of 2S1636-536 in July 1983 the quiescent flux was observed to brighten from 1.7×10 -9 ergs/cm. 2 /sec to 2.6×10-9 ergs/cm. 2 /sec, this increase being accompanied by a decrease in effective temperature. Further analysis of the spectrum reveals that the best fit is a power …