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ROSAT All-Sky Survey/ASIAGO-ESO QSO Survey Catalog

Published by High Energy Astrophysics Science Archive Research Center | National Aeronautics and Space Administration | Metadata Last Checked: February 21, 2026 | Last Modified: 2026-02-17
This table contains some of the first results of a survey for bright quasars (V < 14.5 and R < 15.4) covering the northern hemisphere at Galactic latitudes |b| > 30 degrees. The photometric database is derived from the Guide Star and USNO catalogs. Quasars are identified on the basis of their X-ray emission measured in the ROSAT All-Sky Survey (RASS). The surface density of quasars brighter than 15.5 magnitudes turns out to be (10 +/- 2) x 10<sup>-3</sup> degrees<sup>-2</sup>, about 3 times higher than that estimated by the Palomar-Green (PG) survey. In the paper, the quasar optical luminosity function (LF) at 0.04 < z <= 0.3 is computed and shown to be consistent with a luminosity-dependent luminosity evolution of the type derived by La Franca & Cristiani (1997AJ....113.1517L) in the range 0.3 < z <=2.2. The predictions of semianalytical models of hierarchical structure formation agree remarkably well with the present observations. This table was created by the HEASARC in September 2010 based on the combination of the electronic versions of Tables 2, 3, and 4 from the reference paper which were obtained from the CDS (their catalog J/AJ/119/2540). This is a service provided by NASA HEASARC .

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