Optical Spectroscopy Study Of Moderate-intensity Radio Flat-spectrum Quasars

Using a sample from FIRST Bright Quasar Survey, we separated radio-intermediate flat-spectrum quasars from traditional radio-loud quasars, and compared their optical spectral properties to radio-quiet and radio-loud quasars. We found that the optical spectra of radio-intermediate flat-spectrum quasars are more similar to those of radio-quiet quasars. This supports the idea that these quasars are intrinsically radio-quiet, but appear as radio-loud, because they are relativistically boosted in the jet which is close to the line-of-sight.Following some previous researches, which suggested some potential correlations among the observational properties, we checked some of the the relations with the limited data we have got. We got the similar results to the preceding work with low-redshift samples, but didn't see the correlations drew from high-redshift samples. We didn't found more other interesting similarities between radio-intermediate flat-spectrum quasars and those of radio-quiet or radio-loud.