Anisotropic satellite galaxy quenching modulated by supermassive black
  hole activity
  The evolution of satellite galaxies is shaped by their constant interaction
with the circum galactic medium surrounding central galaxies, which in turn may
be affected by gas and energy ejected from the central supermassive black hole.
However, the nature of this coupling between black holes and galaxies is highly
debated and observational evidence remains scarce. Here we report an analysis
of archival data on 124,163 satellite galaxies in the potential wells of 29,631
dark matter halos with masses between 10$^{12}$ and $10^{14}$ solar masses. We
find that quiescent satellites are relatively less frequent along the minor
axis of their central galaxies. This observation might appear counterintuitive
as black hole activity is expected to eject mass and energy preferentially in
the direction of the minor axis of the host galaxy. However, we show that the
observed signal results precisely from the ejective nature of black hole
feedback in massive halos, as active galactic nuclei-powered outflows clear out
the circumgalactic medium, reducing the ram pressure and thus preserving star
formation. This interpretation is supported by the IllustrisTNG suite of
cosmological numerical simulations, where a similar modulation is observed even
though the sub-grid implementation of black hole feedback is effectively
isotropic. Our results provide compelling observational evidence for the role
of black holes in regulating galaxy evolution over spatial scales differing by
several orders of magnitude.
