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The EMSS Radio Loud Quasar Sample

Anna Wolter·Annalisa Celotti
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Abstract

We construct the first X-ray selected sample of radio-loud quasars from the EMSS survey. The X-ray selection allows us to explore the properties of radio-loud quasars 10-100 weaker than classical samples in the radio band. There are no radio-loud quasars whose synchrotron peak reaches the UV-soft X-ray band at these (radio) flux levels (as occurs for BL Lac objects selected in the X-ray band), but they appear to have comparatively stronger optical-UV emission. We suggest that this can be ascribed to a significant contribution from a quasi-thermal optical-UV component, emerging due to the comparatively weak non-thermal emission. The detection of sources at low radio fluxes also shows the presence of a large population of steep spectrum quasars, and the lack of the predicted turnover in the quasar counts.

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Anna Wolter, Annalisa Celotti. 2000-10-04. The EMSS Radio Loud Quasar Sample. https://arxiv.org/abs/astro-ph/0010086

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