ROSATRLQ - ROSAT Radio-Loud Quasars Catalog
The IAU name or designation of the object, based on its B1950 equatorial co-ordinates.
Right Ascension of the optical object in the selected equinox; this was given to the nearest tenth of a second of time in the original CDS/ADC catalog and in J2000 equinox.
Declination of the optical object in the selected equinox; this was given to the nearest arcsecond in the original CDS/ADC catalog and in J2000 equinox.
The galactic longitude of the optical object.
The galactic latitude of the optical object.
A flag for classification and/or additional information about the object; the following values are used:
type_flag value Meaning S An object for which radio emission has been detected but which does not qualify as radio-loud according to the flux criterion that log(f(5 GHz)/f(2500 A)) > 1. U An object for which no 5 GHz flux density is available. C An object for which the X-ray flux is probably corrupted by another nearby source.
Alternate name from VERON93.
The redshift of the quasar, as taken from the VERON93 Catalog. Notice that a '0' in the third decimal place is mostly an artifact of the machine-readable version of that catalog and that the printed version should be consulted if the user needs to know the actual precision of such a value.
The optical magnitude (often but not always in the Johnson V band), as taken from the VERON93 Catalog.
The radio flux density at 5 GHz in milliJanskies, taken from the 87GB radio survey, the NED database, or from VERON93.
The radio spectral index. For most objects multifrequency radio data are available from NED which allow a good detemination of their radio spectra. For objects with obvious power-law spectra or objects with large scatter in the measured fluxes, the spectral indices are determined by fitting a power-law slope to the data. For objects showing a distinct non power-law spectral shape or with only a few measured flux density values, the authors calculated two-point indices between 5 and 1.4 GHz, if available.
The 'unabsorbed' X-ray flux (in the 0.1 - 2.4 keV bandpass), in units of erg/s/cm2 (or mW/m2), assuming a power-law spectrum, i.e., the flux which would have been measured without any interstellar absorption.
The error in the X-ray flux, based on the 1-sigma statistical error in the count rate only. However, for sources with a small number of total counts (mostly RASS sources), the systematic errors can be of the order of about 30 percent, notice. Also, for strong sources, the assumed simple power-law slope is often an inappropriate representation of the spectrum, so that again there may be a significant systematic error in the quoted X-ray flux. In both of these cases, therefore, the systematic uncertainties can be considerably larger than the purely statistical errors, and the errors given in this catalog should be taken as lower limits.
The X-ray photon index, obtained under the assumption of a fixed Galactic absorption and from a power law fit of the form C*E**(-pi_gal) in the ROSAT energy band. A missing entry means that no reasonable spectral index could be obtained.
The positive 1-sigma error in the X-ray photon index for the assumed Galactic hydrogen column density. If no error is given, its value is unphysically large.
The negative 1-sigma error in the X-ray photon index for the assumed Galactic hydrogen column density. If no error is given, its value is unphysically large.
This parameter give information on the X-ray detection: an 'S' indicates that the object was detected in the All-Sky Survey only, a 'P' indicates that the object was detected only in a pointed observation, and 'SP' indicates that the object was detected in both.
A field that gives a reference code that indicates if other published data were available for an object. The codes and their corresponding references in these cases are as follows:
BP: Buehler P., et al. (1995A&A...295..309B) BH: Brunner H., et al. (1994A&A...287..436B) BW: Brinkmann W. & Siebert J. (1995A&A...300L..33B) EM: Elvis M., et al. (1994ApJ...422...60E) LA: Laor A., et al. (1994ApJ...435..611L) NM: Neumann M., et al. <J/A+AS/106/303> SN: Schartel N., et al. (1996A&A...307...33) SJ: Siebert J., et al., (1996A&A...307....8S) ZY: Zhang Y.F. & Marscher A.P., 1994 AIP Conf. Proc. 313, p.406
The HEASARC browse classification for the radio source: we have set this to `Radio-Loud Quasar' for all entries in this database, except for those entries with type_flag='S' which we have set to `Radio-Quiet Quasar'.