Growing supermassive black holes in the late stages of galaxy mergers are heavily obscured

摘要: Mergers of galaxies are thought to cause significant gas inflows the inner parsecs, which can activate rapid accretion on supermassive black holes (SMBHs), giving rise active galactic nuclei (AGN). During a fraction this process, SMBHs predicted to be enshrouded by and dust. Studying 52 galactic in infrared-selected local luminous and ultraluminous infrared different merger stages hard X-ray band, where radiation is less affected absorption, we find that amount material around SMBHs increases during last phases merger. We Compton-thick (CT, NH ≥ 10^(24) cm^−2) AGN late-merger higher (fCT = 65+12 −13 per cent) than in selected (f CT 27 ± 4 cent), obscuration reaches its maximum when two merging at projected distance of D12 ≃ 0.4–10.8 kpc 77+13 −17 cent). also all our sample in late-merger have > 10^(23) cm^−2, which implies obscuring covers 95+4 −8 cent source. These observations show most effectively funnelled from scale tens parsecs late of galaxy mergers, close environment advanced mergers richer in gas dust with respect isolated galaxies, cannot be explained by the classical unification model torus responsible for obscuration.