dc.contributor.author |
Ghosh, K. K |
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dc.contributor.author |
Soundararajaperumal, S |
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dc.date.accessioned |
2008-07-01T11:45:51Z |
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dc.date.available |
2008-07-01T11:45:51Z |
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dc.date.issued |
1992-02 |
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dc.identifier.citation |
MNRAS, Vol. 254, No.4, pp. 563 - 567 |
en |
dc.identifier.issn |
0035-8711 |
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dc.identifier.uri |
http://hdl.handle.net/2248/2569 |
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dc.description.abstract |
Exosat observations (0.1-10 keV) of the radio-loud quasar 1928 + 73, which displays superluminal motion, were made at four epochs between 1983/283 and 1984/009, and spectra of this source are obtained from the Exosat database. The X-ray spectrum (0.1-10 keV) can be explained by a power law and uniform absorption model. No significant low-energy absorption or soft excess were detected. Both soft (0.1-2 keV) and hard (2-10 keV) X-ray-flux variations of this quasar were found on a time-scale of one month. Spectral-index values obtained from the power-law model suggest that they exceed the 'canonical' value. A thermal bremsstrahlung model also fits well. Uncorrelated variations of the soft and hard fluxes are found in this source which indicate that they have different origins. A soft excess is apparent when the spectra are fitted with a canonical photon index of about 1.7. The spectra presented here are the first in the X-ray region for 1928 + 73 |
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dc.format.extent |
572818 bytes |
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dc.format.mimetype |
application/pdf |
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dc.language.iso |
en |
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dc.publisher |
Blackwell Publishing |
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dc.relation.uri |
http://adsabs.harvard.edu/abs/1992MNRAS.254..563G |
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dc.subject |
Quasars |
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dc.subject |
Satellite Observation |
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dc.subject |
Spectrum Analysis |
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dc.subject |
X Ray Sources |
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dc.subject |
X Ray Spectra |
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dc.subject |
Bremsstrahlung |
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dc.subject |
Canonical Forms |
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dc.subject |
Exosat Satellite |
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dc.subject |
Extragalactic Radio Sources |
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dc.subject |
Heao 2 |
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dc.title |
The X-ray spectrum of the superluminal quasar 1928 + 73 |
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dc.type |
Article |
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