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

BISCHETTI, ManuelaManuelaBISCHETTIFERUGLIO, ChiaraChiaraFERUGLIOD'ODORICO, ValentinaValentinaD'ODORICOArav, N.N.AravBañados, E.E.BañadosBecker, G.G.BeckerBosman, S. E. I.S. E. I.BosmanCarniani, S.S.CarnianiCRISTIANI, StefanoStefanoCRISTIANICUPANI, GuidoGuidoCUPANIDavies, R.R.DaviesEilers, A. C.A. C.EilersFarina, E. P.E. P.FarinaFerrara, A.A.FerraraMaiolino, R.R.MaiolinoMazzucchelli, C.C.MazzucchelliMesinger, A.A.MesingerMeyer, R. A.R. A.MeyerOnoue, M.M.OnouePICONCELLI, EnricoEnricoPICONCELLIRyan-Weber, E.E.Ryan-WeberSchindler, J. -T.J. -T.SchindlerWang, F.F.WangYang, J.J.YangZhu, Y.Y.ZhuFIORE, FabrizioFabrizioFIORE2024-11-252024-11-2520220028-0836http://hdl.handle.net/20.500.12386/35391Bright 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 old1. 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 mass2,3 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 driver4. 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 accretion5.STAMPAenSuppression of black-hole growth by strong outflows at redshifts 5.8-6.6Article10.1038/s41586-022-04608-12-s2.0-85130635813https://www.nature.com/articles/s41586-022-04608-1https://api.elsevier.com/content/abstract/scopus_id/851306358132022Natur.605..244BFIS/05 - ASTRONOMIA E ASTROFISICA