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Thermal radiation from a radio pulsar PSR 1055-52
Aschenbach, B.; Brinkmann, W.; Oegelman, H.
The radio pulsar PSR 1055 - 52 was studied in order to detect thermal radiation from the surface of a neutron star. Einstein satellite observations of PSR 1055 - 52 fitted to different spectra are described. These results and observations of an extended source around PSR 1055 - 52 were used by Cheng and Helfand (1983) to develop the theory of a sy…
EXOSAT 2 10 KeV observations of M87 and the Virgo cluster
Smith, A.; Stewart, G.
A series of observations of the Virgo cluster of galaxies with the Medium Energy experiment on board EXOSAT are presented. These take the form of two orthogonal scans meeting at M87. The observed count rates have been compared with those obtained with the IPC on board the EINSTEIN observatory and are found to be consistent with the the IPC surface…
EXOSAT Le-Canis Observations of the VELA Supernova Remnant
Smith, A.; Zimmermann, H. -U.
Presented here are Exosat LE1-CMA images of fields in the Vela SNR. Soft X-ray emission is observed in the north of the remnant indicating a filamentry structure. No X-ray emission was seen in two fields to the west and south-west which have optical filaments but were not studied by Einstein. The Vela pulsar is observed and is significantly broade…
EXOSAT Observations of the Iron Line Emission of HERCULES-X-1 during a 35-DAY Cycle
Pietsch, W.; Kahabka, P.; Truemper, J. +2 more
In March/April 1984 eleven EXOSAT observations of Her X-1 were performed sampling a full 35 day cycle. Spectral analysis of the ME and GSPC data shows that the iron line emission is present during all phases. During the main-on state we see an iron line at 6.65 ± 0.07 keV with a FWHM of 1 2 keV and an equivalent width of 300 to 400 eV. The high re…
A High Quality Low State Observation of CIRCINUS-X-1
Tennant, A. F.
Cir X-1 was extremely faint when we observed it with EXOSAT. The light curve clearly shows the source in two states; a faint variable state and a very faint but more constant state. The spectrum is very complicated but clearly shows the existence of an iron line.
EXOSAT Observations of the Contact Binary Vw-Cephei
Heise, John; Vilhu, Osmi
EXOSAT observations of the contact binary VW Cephei on 19th March 1984 are presented. The L1-telescope with CMA+thick Lexan filter was used. The observations cover one orbital revolution showing an asymmetrical X-ray light curve. This can be modelled by an active neck, connecting the two stars, and with enhanced coronal regions on the primary star…
MR2251-178: Preliminary results of an X-ray monitoring programme
Pounds, K. A.; Stewart, G. C.; Stanger, V. A.
We present the initial results from an X-ray monitoring programme of the bright QSO MR2251-178.
EXOSAT Observations of the Bl-Lacertae Object MKN421
McHardy, I.; Warwick, R. S.; Pounds, K. A.
The BL Lac object Mkn 421 was observed by EXOSAT four times over a period of six days in February 1984. Significant X-ray variability was apparent on a timescale of less than a day, but with no accompanying spectral change. The source exhibited a very soft power law X-ray spectrum with an extremely low intrinsic column density (NH≲10
X-Ray Optical and Ultraviolet Observations of the Am-Herculis System E2003+225
Mukai, K.; Maraschi, L.; Chiappetti, L. +13 more
The AM Her type object E2003+225 was observed with EXOSAT, IUE and ground-based telescopes on 1983 Oct. 12. The brightness of the ultrasoft X-ray component allowed the Objective Grating Spectrometer (OGS) to be used, which gave a model-independent determination of the temperature of the blackbody spectrum. The star was observed again on 1984 July …
The Discovery of a 25-MIN Regular Modulation in the X-Ray Flux from 2S0142+61
Parmar, A. N.; White, N. E.; Giommi, P. +2 more
A 13 hr observation of 2S0142+61 on 1984 August 27 by EXOSAT shows the X-ray flux of 2S0142+61 to be modulated with a period of 1456+/-6 s. The 1 10 keV spectrum is two component with a ∼0.7 keV thermal and 0.0 energy index power law, with 30% of the total luminosity in the thermal component. The spectrum is absorbed by ∼1 × 1022 H cm