EXOSAT X-ray spectra of quasars
نویسندگان
چکیده
منابع مشابه
High resolution X-ray spectra of quasars
Past X-ray observations by ASCA suggest that warm absorbers (Ovii and Oviii edges) are apparently rare in high luminosity AGNs (quasars) while they are more common in low luminosity AGNs (Seyferts). However, this could be a selection effect if high luminosity AGNs have mostly narrow absorption lines (with no strong bound free edges), which escaped detection by the low resolution of ASCA. To che...
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The results from an X-ray spectral analysis of a large sample of quasars, observed with ASCA, are presented. The sample was selected to include all ASCA observations of quasars, with z > 0.05 and MV < −23.0, available up to January 1998. The data reduction leaves 62 quasars, 35 radio-loud and 27 radio-quiet, suitable for spectral analysis. Differences are found between the radio-quiet quasars (...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 1992
ISSN: 0004-637X,1538-4357
DOI: 10.1086/170851