Details

Autor(en) / Beteiligte

• Bischetti, M.
• Feruglio, C.
• D’Odorico, V.
• Arav, N.
• Bañados, E.
• Becker, G.
• Bosman, S. E. I.
• Carniani, S.
• Cristiani, S.
• Cupani, G.
• Davies, R.
• Eilers, A. C.
• Farina, E. P.
• Ferrara, A.
• Maiolino, R.
• Mazzucchelli, C.
• Mesinger, A.
• Meyer, R. A.
• Onoue, M.
• Piconcelli, E.
• Ryan-Weber, E.
• Schindler, J.-T.
• Wang, F.
• Yang, J.
• Zhu, Y.
• Fiore, F.

Titel

Suppression of black-hole growth by strong outflows at redshifts 5.8–6.6

Ist Teil von

• Nature (London), 2022-05, Vol.605 (7909), p.244-247

Ort / Verlag

London: Nature Publishing Group UK

Erscheinungsjahr

2022

Quelle

MEDLINE

Beschreibungen/Notizen

• Bright quasars, powered by accretion onto billion-solar-mass black holes, already existed at the epoch of reionization, when the Universe was 0.5–1 billion years old 1 . How these black holes formed in such a short time is the subject of debate, particularly as they lie above the correlation between black-hole mass and galaxy dynamical mass 2 , 3 in the local Universe. What slowed down black-hole growth, leading towards the symbiotic growth observed in the local Universe, and when this process started, has hitherto not been known, although black-hole feedback is a likely driver 4 . Here we report optical and near-infrared observations of a sample of quasars at redshifts 5.8 ≲  z  ≲ 6.6. About half of the quasar spectra reveal broad, blueshifted absorption line troughs, tracing black-hole-driven winds with extreme outflow velocities, up to 17% of the speed of light. The fraction of quasars with such outflow winds at z  ≳ 5.8 is ≈2.4 times higher than at z  ≈ 2–4. We infer that outflows at z  ≳ 5.8 inject large amounts of energy into the interstellar medium and suppress nuclear gas accretion, slowing down black-hole growth. The outflow phase may then mark the beginning of substantial black-hole feedback. The red optical colours of outflow quasars at z  ≳ 5.8 indeed suggest that these systems are dusty and may be caught during an initial quenching phase of obscured accretion 5 . A study reporting optical and near-infrared observations of quasars at redshifts 5.8–6.6 shows that about half have strong winds, up to 17% the speed of light, suppressing black-hole growth.