The host galaxies of z=2 radio-quiet QSOs

Abstract

Based on an $R$-band imaging survey of high-redshift ($z\approx 2$) QSOs with the 4.2m WHT, we report the detection of extensions to the nuclear PSFs of two radio-quiet and one radio-loud QSO. The extensions are most likely host galaxies, with luminosities of at least $3-7$\% of the QSO luminosity. The most likely values for the luminosities lie in the range $6-18$\% of the QSO luminosity ($R\sim 19.8-20.9$~mag). Our observations show that, if the extensions we have detected are indeed galaxies, extraordinary massive and luminous galaxies are not only characteristic of radio-loud objects, but of QSOs as an entire class.

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