The EMSS Radio Loud Quasar Sample
نویسندگان
چکیده
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 nonthermal 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.
منابع مشابه
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