A dynamical measure of the black hole mass in a quasar 11 billion years ago

Understand

Tight relationships exist in the local universe between the central stellar properties of galaxies and the mass of their supermassive black hole.

• These suggest galaxies and black holes co-evolve, with the main regulation mechanism being energetic feedback from accretion onto the black hole during its quasar phase.
• A crucial question is how the relationship between black holes and galaxies evolves with time; a key epoch to probe this relationship is at the peaks of star formation and black hole growth 8-12 billion years ago (redshifts 1-3).
• Here we report a dynamical measurement of the mass of the black hole in a luminous quasar at a redshift of 2, with a look back time of 11 billion years, by spatially resolving the broad line region.