We present Atacama Large Millimeter Array 1mm observations of the rest-frame far-infrared (FIR) dust continuum in 27 quasars at redshifts 6.0 ≲ z < 6.7. We detect FIR emission at ≳ 3σ in all quasar host galaxies with flux densities at ∼1900GHz in the rest-frame of 0.12 < Srest, 1900GHz < 5.9mJy, with a median (mean) flux density of 0.88mJy (1.59mJy). The implied FIR luminosities range from LFIR = (0.27-13) × 1012L⊙, with 74% of our quasar hosts having LFIR >1012L⊙. The estimated dust masses are Mdust = 107-109M⊙. If the dust is heated only by star formation, then the star formation rates in the quasar host galaxies are between 50 and 2700M⊙ yr-1. In the framework of the host galaxÿCblack hole coevolutionmodel a correlation between ongoing black hole growth and star formation in the quasar host galaxy would be expected. However, combined with results from the literature to create a luminosity-limited quasar sample, we do not find a strong correlation between quasar UV luminosity (a proxy for ongoing black hole growth) and FIR luminosity (star formation in the host galaxy). The absence of such a correlation in our data does not necessarily rule out the coevolution model, and could be due to a variety of effects (including different timescales for black hole accretion and FIR emission).
|Original language||English (US)|
|State||Published - Sep 5 2018|
- Galaxies: High-redshift
- Galaxies: Star formation
- Galaxies: Statistics
- Quasars: General
ASJC Scopus subject areas