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Optical Detection of the Hidden Nuclear Engine in NGC 4258
(IOP Publishing, 1995)
The subparsec masing disk recently found to be orbiting a central mass of ~3.6 × 107 M☉ in the Seyfert/LINER galaxy NGC 4258 (Miyoshi and coworkers) provides the most compelling evidence to date for the existence of a ...
The Complex Optical to Soft X-Ray Spectrum of Low-Redshift Radio-quiet Quasars. II. Comparison with Free-Free and Accretion Disk Models
(IOP Publishing, 1995)
We compare the optical to soft X-ray spectral energy distributions (SEDs) of a sample of bright low-redshift (0.048 < z < 0.155), radio-quiet quasars, with a range of thermal models which have been proposed to explain the ...
Multifrequency observations of KAZ 102 during the ROSAT all-sky survey
(IOP Publishing, 1995)
The bright quasar Kaz 102, which lies in the vicinity of the North Ecliptic Pole, was monitored during the ROSAT All Sky Survey for 121.5 days from 1990 July 30 to 1991 January 25. In the course of the survey, optical ...
Testing Models for the Quasar Big Blue Bump via Color-Color Diagrams
(IOP Publishing, 1995)
We discuss several models of quasar big blue bump emission in color-color and color-luminosity diagrams. We define several broad passbands: IR (0.8-1.6 μm), VIS (4000-8000 Å), UV (1000-2000 Å), UV1 (1400-2000 Å) and UV2 ...
Testing Unified X-Ray/Ultraviolet Absorber Models with NGC 5548
(IOP Publishing, 1995)
The bright Seyfert galaxy NGC 5548 shows absorption features in its X-ray and UV spectra. The large amount of optical/UV and X-ray monitoring data available for this object makes it an ideal candidate to test our model of ...
The Cambridge-Cambridge ROSAT Serendipity Survey - III. VLA observations and the evolution of radio-quiet and radio-loud objects
(Oxford University Press (OUP), 1995)
We present the results of the VLA radio observations at 1.475 GHz (20 cm) of the active galactic nuclei (AGN) in the Cambridge-Cambridge ROSAT Serendipity Survey (CRSS), a sample of 123 faint X-ray sources with ...
The Cambridge–Cambridge ROSAT Serendipity Survey – II. Classification of X-ray-luminous Galaxies
(Royal Astronomical Society, 1995)
We present the results of an intermediate-resolution (1.5\AA) spectroscopic study of 17 X-ray luminous narrow emission-line galaxies previously identified in the Cambridge-Cambridge {\it ROSAT} Serendipity Survey and the ...
The Unusual Quasar PG 1407+265
(IOP Publishing, 1995)
PG 1407+265, discovered in the Palomar-Green Survey (Schmidt & Green 1983), was identified as a z ˜ 1 radio-quiet quasar on the basis of a single weak line. Further observations over a wide wavelength range confirm the ...