We used the 1.4GHz NVSS to study radio sources in two color-selected QSO samples: a volume-limited sample of 1313 QSOs defined by M_i_<-23 in the redshift range 0.2<z<0.45 and a magnitude-limited sample of 2471 QSOs with m_r_<=18.5 and 1.8<z<2.5. About 10% were detected above the 2.4mJy NVSS catalog limit and are powered primarily by active galactic nuclei (AGNs). The space density of the low-redshift QSOs evolves as {rho}{prop.to}(1+z)^6^. In both redshift ranges the flux-density distributions and luminosity functions of QSOs stronger than 2.4mJy are power laws, with no features to suggest more than one kind of radio source. Extrapolating the power laws to lower luminosities predicts the remaining QSOs should be extremely radio quiet, but they are not. Most were detected statistically on the NVSS images with median peak flux densities S_p_(mJy/beam){approx}0.3 and 0.05 in the low- and high-redshift samples, corresponding to spectral luminosities log [L_1.4GHz_(W/Hz)]{approx}22.7 and 24.1, respectively. We suggest that the faint radio sources are powered by star formation at rates dM/dt~20M_{sun}/yr in the moderate luminosity (median {approx}-23.4) low-redshift QSOs and dM/dt~500M{sun}_/yr in the very luminous ({approx}-27.5) high-redshift QSOs. Such luminous starbursts [~11.2 and 12.6, respectively] are consistent with "quasar mode" accretion in which cold gas flows fuel both AGN and starburst.

Cone search capability for table J/ApJ/768/37/nvssqsos (NVSS-detected QSOs in redsfhit range 0.2<z<0.45 or 1.8<z<2.5)