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arXiv · 1511.07432

Bright [CII] and dust emission in three z>6.6 quasar host galaxies observed by ALMA

B. P. Venemans·F. Walter·L. Zschaechner·R. Decarli·G. De Rosa·J. R. Findlay·R. G. McMahon·W. J. Sutherland
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Abstract

We present ALMA detections of the [CII] 158 micron emission line and the underlying far-infrared continuum of three quasars at 6.6 ~6 quasar hosts correlate with the quasar's bolometric luminosity. In one quasar, the [CII] line is significantly redshifted by ~1700 km/s with respect to the MgII broad emission line. Comparing to values in the literature, we find that, on average, the MgII is blueshifted by 480 km/s (with a standard deviation of 630 km/s) with respect to the host galaxy redshift, i.e. one of our quasars is an extreme outlier. Through modeling we can rule out a flat rotation curve for our brightest [CII] emitter. Finally, we find that the ratio of black hole mass to host galaxy (dynamical) mass is higher by a factor 3-4 (with significant scatter) than local relations.

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B. P. Venemans, F. Walter, L. Zschaechner, R. Decarli, G. De Rosa, J. R. Findlay, R. G. McMahon, W. J. Sutherland. 2015-11-23. Bright [CII] and dust emission in three z>6.6 quasar host galaxies observed by ALMA. https://doi.org/10.3847/0004-637x%2F816%2F1%2F37

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