Rapid evolution and transformation into quiescence?: ALMA view on z > 6 low-luminosity quasars

Date

2020

Authors

Izumi, Takuma
Onoue, Masafusa
Matsuoka, Yoshiki
Nagao, Tohru
Strauss, Michael A.
Imanishi, Masatoshi
Kashikawa, Nobunari
Fujimoto, Seiji
Kohno, Kotaro
Toba, Yoshiki

Journal Title

Journal ISSN

Volume Title

Publisher

Cambridge University Press

Abstract

We present ALMA [CII] line and far-infrared (FIR) continuum observations of seven z > 6 low-luminosity quasars (M1450 > −25 mag) discovered by our on-going Subaru Hyper Suprime-Cam survey. The [CII] line was detected in all targets with luminosities of ∼(2−10) x 108 L⊙, about one order of magnitude smaller than optically luminous quasars. Also found was a wide scatter of FIR continuum luminosity, ranging from LFIR < 1011L⊙ to ∼2 x 1012L⊙. With the [CII]-based dynamical mass, we suggest that a significant fraction of low-luminosity quasars are located on or even below the local Magorrian relation, particularly at the massive end of the galaxy mass distribution. This is a clear contrast to the previous finding that luminous quasars tend to have overmassive black holes relative to the relation. Our result is expected to show a less-biased nature of the early co-evolution of black holes and their host galaxies.

Description

Keywords

quasars: general, galaxies: evolution, galaxies: high-redshift

Citation

Source

Proceedings of the International Astronomical Union

Type

Journal article

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Restricted until

2099-12-31