The Multiple Merger Assembly of a Hyper-luminous Obscured Quasar at
  redshift 4.6
  Galaxy mergers and gas accretion from the cosmic web drove the growth of
galaxies and their central black holes at early epochs. We report spectroscopic
imaging of a multiple merger event in the most luminous known galaxy, WISE
J224607.56-052634.9 (W2246-0526), a dust-obscured quasar at redshift 4.6, 1.3
Gyr after the Big Bang. Far-infrared dust continuum observations show three
galaxy companions around W2246-0526 with disturbed morphologies, connected by
streams of dust likely produced by the dynamical interaction. The detection of
tidal dusty bridges shows that W2246-0526 is accreting its neighbors,
suggesting merger activity may be a dominant mechanism through which the most
luminous galaxies simultaneously obscure and feed their central supermassive
black holes.
